> The objective of this book is to provide guidelines for engineers helping them to improve machine lifetime performance and reliability. Needed in equipment design is a design-for-reliability approach that takes into account all life-cycle costs (acquisition, installation, operation, maintenance, repair, and salvage). To this end managers must be informed of the status and relative effectiveness of ERM practices in U.S. and foreign industries. Here, is the load factor, is the size factor, is the surface factor, is the temperature factor, is the reliability factor and is the unmodified endurance limit. Reliability testing will be performed at several levels. and vertically to supervisory controllers above or slaves below. Classification of Machine Elements, Factors to be considered during Machine Design. FIGURE 3-5 For photolithography, attempts to increase mean time between failures have yielded a 30% increase in availability and an approximately 30% decrease in area throughout, while achieving a 10% reduction in total fabrication throughput time. In many companies, career paths for these employees are deemphasized, and responsibility for their training and development is specifically assigned to no one. Building a workforce with the multidisciplinary skills needed for competitiveness. This factor is called the safety factor. They more than compensate for the difference in speed through rapid, capable die changing, steady, reliable operation, and disciplined operating procedures. ERM does not begin on … Normal Operating Conditions:These are conditions, which let the system or product performs to the optimum level without stress. design-out maintenance. Indirect benefits often outweigh direct savings. Jump up to the previous page or down to the next one. Use of standard parts: There should be maximum possible standard parts in the design of the machine. Who is, and is not, walking the floors of today's plants is also of concern. While this does not mean that U.S. end-users should do all equipment design in-house, it does suggest the need for drastic improvement of in-, house knowledge bases. Reliability is extremely design-sensitive. By increasing uptime and yields of good parts, ERM can reduce capital requirements, thereby cutting total production costs. Executive management awareness of present ERM practice in the United States and abroad, and its importance for competitiveness. The theoretical capacity of a manufacturing process or machine is the output per unit of time of continuous operation at the maximum safe operating speed. More importantly, the important maintenance issues do not surface. Equipment reliability and maintenance practices for better returns on capital investment. The productivity of these investments is a fundamental element of competition among companies and nations. Firms that do value ERM, typically driven by powerful cus-. This is the value of “n” that should be applied in the nominal design … The optimal maintenance and reliability program for a plant provides the right maintenance on the right assets at the right time. For instance, we often speak about a machine as reliable: “I have a reliable car.” Without a measurement system that can quantify relationships between engineering work and profit/asset benefits, assess the costs of equipment waiting (e.g., load, unload, operator, material) and downtime, and allocate maintenance costs to reflect reality, results will be anecdotal and perception of the basis for changing the incentive structure will remain shaky. (excerpt from: Kaplan, R. S. 1986. A standard methodology for measuring the performance of ERM is needed, as is a way to quantify the benefits of ERM for top management. The ERM techniques of Japanese firms are basic practices that are carried out religiously. divided by the factor of safety. Operational changes that will enhance ERM must be identified. Compliance with state standards: Following the standards makes designing easier and availability of various parts faster and easier. Though the uncertainties involved make exact predictions impossible, designers can solve many problems based on past experience, trial and error, tests, and the like. Source: Intel Corporation, 1989. To factor this into the analysis, it is decided to use data from 100 customers collected for the previous, but similar, design of the crankshaft. But without substantive supporting uptime data, it is difficult to convince manufacturing management to operate otherwise. Light weight and minimum dimensions: The machine elements and machine should be strong, rigid and wear resistant with minimum weight and least dimensions. It is usually denoted as probability or as a success. These definitions are important when comparing data for different firms in an industry. This approach should delineate basic principles that are demonstrably effective and universally applicable. All Rights Reserved. 6–17 A more enlightened approach to reducing equipment life-cycle costs would be to increase capital investment at the concept and design stages in order to improve equipment reliability, maintainability, and predictability and thereby reduce operations and support costs that inflate factory overhead (Figure 3-6). Across each industry is a reli-. Viewed as a discrete activity performed at different points in the manufacturing process, ERM will not achieve its full potential. Show this book's table of contents, where you can jump to any chapter by name. At the early design stage, Reliability Predictions enable you to perform an assessment of likely failure rate characteristics. Factors to be considered during Machine Design: Part-1, Factors to be considered during Machine Design: Part-2, Skills a Good Machine Designer should possess, Commercial Energy Usage: Learn about Emission Levels of Commercial Buildings, Time to Upgrade Your HVAC? While they are generally effective, these practices have been considerably enhanced by state-of-the-art maintenance planning, management, and implementation technologies that incorporate information on equipment design, application, and operation. This testing helps discover many problems in the software design and functionality. The trend toward integrating mechatronic equipment into factorywide systems provides a framework for extensively exploring and exploiting this approach. The suppliers, largely isolated, are in most cases not likely to commit resources to providing a capability that many U.S. manufacturers, because they have not yet understood its value, have not demanded. Results of these performance comparisons are published in the trade press. Software and sensors have the potential to enhance ERM and so mitigate the added complexity associated with these technologies (see Figure 3-1). What are Machine Elements? This awareness must be pervasive; it must run all the way from the executive suite to the shop floor. Number of machines to be built: Designing of the machine will depend a lot on the number of machines to be manufactured. Mean time between failures for a wide variety of assembly equipment has increased in the range of 200 to 2300 percent, resulting in equipment uptime averages in excess of 90 percent of available hours (in a 168-hour week). Aishin Seiki's success reflects neither high technology nor large investments in new facilities. Reliability Leads to Profitability:This highlights that consistent reliability exhibited by product or system leads to increase in … decisions at the conceptual level, and an understanding of the accounting issues involved. Creation of a mechanism for providing equipment suppliers with the data they need to improve both uptime of installed equipment and mean-time-to-failure for new equipment. Veteran engineers in one Japanese company with fewer than 50 employees, for example, developed all of the firm's equipment, tools, and dies. Breakdown maintenance and repair is the after-the-fact restoration of failed equipment. The ideal manufacturing environment of the future has no maintenance organization and every piece of equipment is expected to be available 100 percent of the time. For this the machine should be designed for least maintenance requirements and long-life. Quantifiable reasons must be found for employing technologists in the manufacturing sector of an enterprise. This can be achieved by using light weight rolled sections and hardening the metals. If you think about how we use the word “reliable” in everyday language, you might get a hint. Reliability Testing is one of the key to better software quality. Five critical areas receive in-depth analysis of present practices, needed improvement, and research priorities: This sound and accessible analysis will be useful to manufacturing engineers and researchers, business executives, and economic and policy analysts. Reliability: The reliability of the machine is a very important if the machine has to find the huge market in the business. All rights reserved. If the vision set forth in this report is ever to be realized, the skills and capabilities that will be needed by managers at each level of the organization, and the agencies and institutions—universities, industries, companies, community colleges, etc.—best positioned to cultivate these skills, must be identified. Durability : The longer the life of the machine more it develops the reputation of being the dependable machine and more will be its sale. Before anything can be done about equipment, U.S. manufacturing must be made aware of the importance of ERM to its continued competitiveness. The Japanese have done it by adhering to the basic principles of motivation, commitment and understanding, and training and discipline. The way users operate the system 1. Needed are more career or professional engineers from interdisciplinary programs that cut across engineering disciplines to also embrace elements of business, psychology, and sociology. The cumulative effect of these practices is reflected in the product—mass-produced automobile body parts that are. In fact, to the extent that they lead management to treat maintenance as an indirect cost that increases factory overhead, these systems may be putting the U.S. asset base at risk. In firms whose management understands facility issues, including the implications of ERM efforts, just-in-time (JIT)1 is less a measure of inventory than an indication that all processes are under control. It must be viewed as a system within the larger manufacturing system, a system that can be modeled in successful operation. How is the safety factor calculated. Inquiries into ERM in the next generation of equipment should be based on practical investigations into improving it in the present generation. Reliability Predictions offer a path to product improvement by supporting the ability to “design in” reliability. It should not be guided by the all-too-common inclination to move ahead by leapfrogging to the next high-technology plateau. Harvard Business Review 64(2): 87-95.). Most process engineers employ a deterministic safety factor approach that reflects a reasonable level of unavoidable loss of output. For completely new designs, however, alternative means of estimating reliability must be employed. There is no reason to expect that they will not respond similarly to a reemphasis on manufacturing. As the shafts transmitting power are subjected to fatigue loading, therefore higher factor of safety of 3 to 4 is used on the basis of yield strength for static load analysis. This correct diagnosis avoided both an unscheduled outage for repair and a probable forced outage later had the problem gone undetected during the scheduled outage. Results in trial fabrication plants for both wafer etch and implanter equipment show a substantial increase in average monthly uptime and increased predictability by reducing the range of monthly. Rather, it is the result of a strategy for achieving zero defects and zero breakdowns through common-sense engineering, attention to basics, and hard work and team effort guided by a top-management vision. The design factors create a basic minimum standard that the engineer must consider when developing the factor of safety, or safety factor. ERM does not begin on the manufacturing. The strategy was implemented in four stages. To this end, research in the area of ERM should be directed at finding ways to: inculcate the attitude that equipment should improve through use;use; identify and analyze operational changes that might enhance ERM and inform equipment suppliers of these changes; communicate ERM requirements in clear, operational terms; support industrywide collection and analysis of standardized ERM data; foster an understanding of enterprise optimization; and. Most of these are focused on selection and computation of basic machine elements. comparable, if not superior, to those produced by manufacturers of low volume, luxury cars. The problem needs to be viewed in its totality, with a balanced emphasis on human and technological issues and barriers. 3. It is defined as the ratio between the strength of the material and the maximum stress in the part. To maintain competitiveness in the emerging global economy, U.S. manufacturing must rise to new standards of product quality, responsiveness to customers, and process flexibility. Product and process engineers should be involved in manufacturing decision making, with financial analysts supplying guidance. Appearance of the machine: While designing the machine the aesthetics and ergonomics of the machine should be given due consideration without affecting its functionality. Effective management of ERM requires realistic awareness of the benefits of and necessary decisions related to ERM, the technical knowledge that will permit managers to make appropriate. U.S. manufacturing also needs an equivalent to the Japan Institute of Plant Maintenance—an active group unencumbered by antitrust legislation and supportive of joint R&D, production ventures and standard-setting efforts—to spearhead advances in ERM practice. Historically, the evolution of ERM can be traced from breakdown maintenance and repair to preventive maintenance to predictive maintenance. A better job of debugging these systems via simulation, analysis, and rapid development needs to be done. Ready to take your reading offline? The origins of the field of reliability engineering, at least the demand for it, can be traced back to the point at which man began to depend upon machines for his livelihood. ERM practices contribute significantly to this achievement. Managers and engineers should be aware of the benefits of using simulation methodology during process design. Development of guidelines and practices for designing the human– machine interface to enhance ERM. The Japanese stamping lines, for example, are specified to run at a lower, more reliable rate than equivalent U.S. lines. FIGURE 3-6 An enlightened approach to reducing equipment life cycle costs: Increase capital investment at the concept and design stages. Development of systematic, disciplined methodologies that will enable manufacturers to communicate equipment requirements in clear operational terms. Attainment of set performance levels by equipment is celebrated with the sipping of sake. You're looking at OpenBook, NAP.edu's online reading room since 1999. A new attitude that equipment should improve through use. Reliability data from the existing systems can be considered for the new designs if the new design is quite similar to the current systems. Reliability Factor k e From Fig. The key technology in stamping is the transfer press, which incorporates a mechanism for moving parts between five or six dies. Designers have access to comprehensive data from the equipment itself, as well as a wealth of information about the needs and performance of the installed base of industrial users. Well-maintained machines hold tolerances better, help to reduce scrap and rework, and raise part consistency and quality. To evaluate the cost of machine downtime, one must first know a machine 's value per unit of time, which can be obtained through a variety of methods related to capacity utilization (see definition of theoretical capacity on p. 55). Source: VLSI Research Inc. Key elements of the design/development phase include training and development to enable suppliers to perform highly specialized equipment analyses, such as failure modes and effects criticality analysis (FMECA), fault tree analysis, design for testability, design for fault tolerance/isolation/tracking, and design for remote diagnosis. In the area of human–machine interface, research is needed to delineate the guidelines and practices needed for establishing this important junction. Given customer preoccupation with initial cost and technical features, equipment is frequently designed to perform specific tasks within the constraints of an acquisition budget, with little regard for optimizing economic performance over its lifetime. Factor of safety (FoS), also known as safety factor (SF), is a term describing the structural capacity of a system beyond the expected loads or actual loads. Development of a standard methodology for data analysis. This would be helped greatly by a competitiveness assessment that reflects ERM differentials. Dies are cleaned and lubricated routinely, and repairs are completed to original specifications before problems become major. Suppliers are responding by applying microcomputer technology to more phases of manufacturing operations and processing. Scheduled output is the output expected from an operation for a given allocation of time, material, and labor; it is usually based on a published output rate. High acquisition and operating costs (stamping dies and presses constitute a substantial part of the capital investment in automobile manufacture) lead automakers to run multiple sets of dies on a given line. Ease and simplicity of servicing and control: The machine and its element should be simple enough so that very little maintenance and servicing is required. SUBSTANTIAL CAPITAL investments, in the form of facilities and equipment, are required for manufacturing almost all goods of economic significance. HVAC: Heating, Ventilation & Air-Conditioning, Factors to be considered while Designing Machine, This post is part of the series: Machine Design or Mechanical Design. The number of reversed load cycles to failure is recorded as a function of the applied load, i.e. A machine running 24/7 might experience the failure mode of fatigue as it nears the end of its life. Well-understood methods of directing the work of these technologists are needed, as are mechanisms for implementing the results they achieve. A strawman model that would support analysis of the impacts of various methodologies on the manufacturing environment would be useful. A Strategic Industry at Risk. Reliability is the probability that a product will continue to work normally over a specified interval of time, under specified conditions. Reliability:This highlights performance of product or system within a known set of parameters. Development of a standard methodology for measuring ERM. U.S. manufacturing will want to jump to this futuristic plane from its present plateau. to equipment failure. Source: Intel Corporation, 1989. floor; it begins in the office with the design of product, process, and equipment. The implementation stage calls for (1) ensuring early successes and hands-on experience by focusing initial efforts on equipment that offers the most potential for improvement, (2) establishing an autonomous maintenance program for operators, (3) creating a system of planned maintenance that anticipates an increase in work load, (4) improving operating and maintenance skills through training, and (5) developing a prototype equipment management program. It also can shorten lead times by reducing downtime and the need for retooling. Development of standards for design and test, for measuring and evaluating ERM, and for operator–equipment interfaces, would be a great facilitator in each of the areas discussed above. To. Definitions  Reliability - The ability of an item to perform a required function under stated conditions for a stated period of time. The actual uptime of a resource as a percentage of its expected uptime. Over time, a host of little investments, each of which delivers savings in labor, material, or overhead cost, can add up to a less-thanoptimal pattern of material flow and to obsolete process technology. The cost of a typical state-of-the-art manufacturing facility for semiconductor memory chips has risen eightfold since 1980, from $25 million to $200 million. U.S. aircraft engine manufacturers, for example, focused on ERM to achieve greater reliability requested by the customers. Use of easily available materials: Materials selected for the machine elements during the design should be available easily and lowest possible costs. One reliability indicator comes from Weibull plots. Although more recent data are not available, the consensus is that the situation has changed little in the past decade. The techniques that comprise design for reliability include (1) failure modes and effects analysis, (2) robust parameter design, (3) block diagrams and fault tree analyses, (4) physics-of-failure methods, (5) … When a test has a reliability of 0.8, the number of items the test has to be lengthened to get a reliability of 0.95 is estimated in the following way: Hence the test is to be lengthened 4.75 times. This trend is producing a generation of catalog engineers who are adept at ordering equipment from a catalog but who lack the knowledge to evaluate equipment designs. The term artificial intelligence is appearing in sales literature that increasingly is offering catalog solutions as alternatives to technical proficiency. The hard data needed to make a convincing argument to management are hard to find. Science 245 (August 25): 819-823. 4. Testability is a fundamental criterion for design, and an arsenal of reliable testing methods has given rise to equipment that facilitates experimentation. This will help reduce the cost of the machine and ensure easy availability of the parts. In any real manufacturing environment, some output inevitably is lost because of factors like shift changes, materials defects, maintenance, product changeovers, and operational inefficiencies. No available method of measuring system reliability (e.g., equipment effectiveness = availability × speed ratio × yield) has yet been widely accepted by U.S. manufacturers, and manually collected production downtime data are questionable, inasmuch as waiting time for repairs is seldom reported. Reliability engineering is a sub-discipline of systems engineering that emphasizes the ability of equipment to function without failure. Many U.S. manufacturing managers do not. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website. In the introduction stage, the ERM program is kicked off. While judgment is required to ensure that manufacturing equipment is efficiently utilized, sensor technologies and self-diagnostics may be sufficient to ensure that it is reliably maintained. Intelligent manufacturing control for improved reliability and greater precision. This vision for ERM is rooted in the evolution of product and process design and intelligent. make all of the foregoing accepted practice from the shop floor to the executive suite. This volume presents a concise and well-organized analysis of new research directions to achieve these goals. Predictive maintenance, in use in U.S. industry for only four or five years, is usually understood to involve the use of computer software to detect conditions that might eventually lead. Current emphasis should shift from graduating applied scientists and specialists to producing engineers and interdisciplinarians. For example, the mouse on your computer might have a reliability of 0.990 (or 99%) over the next 1000 hours. Essentially, how much stronger the system is than it usually needs to be for an intended load. Ease and simplicity of disassembly: Like assembly, the disassembly of the machine also should be easy so as to easily carry out replacement of the parts, and repair and maintenance of the machine and machine elements. ing system design, simulation fosters a total systems approach to design. Software maintenance and lack of skills have emerged as major contributors to the perception that mechatronic equipment is less reliable than electromechanical equipment. No produce can be manufactured without designing it. Technology management is becoming an accepted discipline in a growing number of U.S. academic institutions. It is conflicting because you design-out maintenance problems so there is no need for maintenance. SOURCE: Lawrence Livermore Laboratory. Cost models associated with short-term measures, which rapidly drive future costs to zero in a present value analysis using a relatively high rate of return, lead managers to emphasize initial purchase price in equipment acquisition. Events that slow or interrupt the manufacturing process or degrade the product impair the competitiveness of a manufacturing enterprise. Design for Reliability What is Product Reliability? Die change time, which necessarily represents scheduled machine downtime, is a critical element of overall operating performance, and rapid, efficient die changing is a key basis of competition in stamping operations. If the results of manufacturing technology research are to be effectively coupled to practice, a systematic, interdisciplinary attack—involving engineering, business, psychology, sociology, and finance, to name a few—must be mounted in order to change the status quo. In test taking, as in many other activities, most people perform better on some days than on others. The use of first-class equipment, operating at full capacity, is vital to competitiveness in the world market, a fact U.S. manufacturing managers must be made to believe and given the tools to act upon. 6–17, S' e = 0.5 S ut is typical of the data and represents 50% reliability. Small investments (under $100,000, say) may need only the approval of the plant manager; expenditures in excess of several million dollars may require the board of directors' approval. Good design engineers must consider so many factors when designing a part or component. Arguments that blame insufficient capacity on old machines that cannot be replaced because of high cost are suspect because the most cost-effective increase in U.S. manufacturing capacity may well be achievable through improved maintenance practices for existing equipment. ning, the cost of generator outages, prevention of in-service failure, and the increasing percentage of older units in service. As a result, it is difficult to make comparisons, share results and good practices among cooperating operations, and measure ERM performance trends in any one factory in a universally credible way. 2. Must CIM be justified by faith alone? Economy of repairs and maintenance: While designing the machine elements and machine the designing should be such that least amount of repairs and maintenance will be required for the machine. For example, meeting process parameters more reliably via FMECA increases factory yields and reduces work-in-process inventory. Some two-year colleges are already cooperating with manufacturers to teach technical skills to shop floor personnel. Making progress with people-related issues will be much harder than solving technological problems. The uptime of a facility, infrastructure component, machine, device, service, product, function, system, business capability or process. Reliability engineering 2. 6.4.4 Reliability Factor (K rel) Endurance limit obtained experimentally is the mean value and it varies even for same material and conditions. Their technology exchange programs today include concurrent engineering of next-generation equipment for new product and process requirements and replacement of Intel factory equipment engineering and maintenance staff with supplier personnel. Between 1979 and 1982, the Japanese Nishio pump factory of Aishin Seiki reduced equipment breakdowns from 700 per month to effectively zero, while achieving an extraordinary level of quality— 11 defects per 1 million pumps produced. Register for a free account to start saving and receiving special member only perks. design trade-off between reliability and maintainability. Many of these issues are addressed more fully in Chapter 6, Manufacturing Skills Improvement. Present problems need to be resolved at a practical level, while high-technology approaches to ERM are developed in the next generation of equipment. The design, construction, maintenance, adjustment, calibration, and use of measuring and of manufacturing equipment are factors which impact on the reliability of the product. Moreover, Japanese plants are characterized by a highly disciplined approach to basic housekeeping—floors and manufacturing equipment are kept spotlessly clean. Several tests are required at each load level to account for the statistical nature of the failure mechanism. Reliability; Theory of Reliability; Theory of Reliability. The very terminology of ERM can impede its adoption and practice. To assess the safety of a design, designers need a simple factor which will help in understanding if a design is safe enough. Managers with this understanding can take a plant beyond the benefits of JIT to realize the potential benefits of ERM. It cannot. In 1980, U.S. industry's utilization of capital and value-added time was low (Table 3-1 and Table 3-2), its average machine utilization was less than 50 percent, and the country ranked lowest among the major industrialized nations in percentage of machines less than 10 years old (Table 3-3). Procurement specifications have been upgraded to require that all key process equipment suppliers have a basic level of ERM expertise. 4. Emphasis on sensor technologies and self-diagnosis. Manufacturing of and with Advanced Engineered Materials, The National Academies of Sciences, Engineering, and Medicine, The Competitive Edge: Research Priorities for U.S. Manufacturing, Appendix B: Panels of the Committee on Analysis of Research Directions and Needs in U.S. Manufacturing. Similar results are being achieved in old as well as new factories throughout Japan. Standards are published for maintenance and operation and for comparing performance of aircraft engines. Even with greater awareness and understanding of ERM and sufficient good data to convince top management of its value, a serious deficit in the technical skills infrastructure required to implement an effective ERM program would still have to be overcome. Reliability describes the ability of a system or component to function under stated conditions for a specified period of time. With an aging complement of steam turbine generators and few new plants in the planning cycle, the U.S utilities industry is responding to increasing demand for electricity by adopting new practices for maintaining and improving the availability of existing equipment. Too often, engineers work hard to improve one element of a system, only to discover that in doing so they have degraded the total system. Also, you can type in a page number and press Enter to go directly to that page in the book. Washington, D.C. November 1989. Reliability—which may be the driver for a few key components or safety features, but is generally a secondary consideration for entire systems— is usually built in after the fact on the basis of experience and limited information. If few numbers of machines are to be manufactured then expensive materials and high production costs can be considered, but for the mass production economy of the machine should be top priority. Equipment design employs new approaches that use broader data bases. In U.S. manufacturing, equipment availability is generally ensured by the existence of standby equipment, i.e., buying two machines when one will produce the desired throughput. Reliability factor to modify endurance limit can be taken as: tomer demands or regulatory influences, are forced overseas in their search for suppliers who are willing to quantify machine reliability and to work to meet ERM goals. Share a link to this book page on your preferred social network or via email. Few U.S. manufacturers have programs that provide white collar staff with exposure and experience in the actual manufacturing process. Workshops sponsored by the National Research Council could serve to acquaint manufacturing executives with present practice in the United States and Japan. FIGURES 3-3 and 3-4 Results in trial fabrication plants for both implanter equipment (1987-8) and wafer etch equipment (1988), with and without service contract, show a substantial increase in average monthly uptime and increased predictability by reducing the range of monthly uptime. Management leadership is essential to solving manufacturing 's problems because only management is positioned to have the overview essential for effective decision making and leading. Needed is a production monitoring system capable of providing information about all machine shutdowns, classifying discrete events, and aggregating these events within categories. The Noria, for instance, is an ancient pump thought to be the world’s first sophisticated machine. This is a calculated value, and is sometimes referred to, for the sake of clarity, as a realized factor of safety. Preventive maintenance, therefore, loses its urgency and breakdown maintenance becomes the order of the day. Just-in-time (JIT) is a method of manufacturing by which parts and assemblies are made or delivered as needed, thereby greatly reducing inventory. A conservative specification of rated capacity, however, can yield misleading data for equipment performance. (See Chapter 6, Manufacturing Skills Improvement for more on this topic.). Still, the system has served the utility well. Management accounting for advanced technological environments. An understanding of enterprise optimization. The Nishio factory is not an isolated showcase. ERM affects drastically the three key elements of competitiveness —quality, cost, and product lead time. The U.S. view is that “the equipment is now performing at its best and over time performance will degrade.” The Japanese view is that “the equipment is now performing at its worst and work needs to be done to improve its performance dramatically.”, Emphasis on short-term profitability at the expense of preventive maintenance programs, personnel, and spare parts actually decreases long-term profitability by increasing the frequency of catastrophic events (i.e., breakdowns that demand emergency repair). 2. Development of industry-wide collections of ERM data. Cost: Cost has always been the major factor of consideration while designing the machine elements or machine and in this age of competition it has become more important. Although companies technically unprepared to deal with these problems stand to suffer increased costs and reduced capacity, extreme pressure to minimize current-period costs continues to lead operations managers to sacrifice the hiring and training of maintenance personnel. In general, manufacturing has been slow to recognize the value of the scientific base; it has placed inordinate value on activity (go fast to go slow) and subscribed to a trial and error approach to problem solving that fails to attack root causes. One utility moved from manual plotting of stator performance data to a computer-based, continuous monitoring system on its 10-year-old turbines that were installed in the mid-1980s. By allowing the ERM process to be modeled dur-. Such a model should address matching of capabilities, design issues and rules, maintenance, installed base, culture, and organization. The Japanese are succeeding at this because they have an integrated view of manufacturing as a system. Critical specifications must be defined and formulated to ensure reliability and identify pitfalls, stumbling blocks, and best practice. Restoration of apprenticeship programs and manufacturing laboratories. Over the next several product generations, the cost of such facilities is expected to reach between $500 million and $750 million (Figure 3-2 ). Manufacturing is easily the most challenging and complex system in any organization. The repair and maintenance of the machine should be easy and cheap and simple replacements should be available. The replacement and displacement of conventional electro-mechanical factory equipment by mechatronic equipment have given rise to a very different set of reliability and maintenance requirements. FIGURE 3-1 Improvements in equipment reliability with increasing computerization. Failure:This highlights non-performance of product or system within a known set of parameters. effectively promote ERM, a clear and strong initiative is needed to identify what needs to be changed, what the objective should be, and how to make the change, in order to have an immediate and significant impact with lasting effects. What is Mechanical Design or Machine Design? 1989. Development of a strawman model for analyzing the impact of various methodologies on the manufacturing environment. uptime (Figure 3-3 and Figure 3-4). 6 6 6. These figures are often given on a yield basis (e.g., output per unit of time or material input). A required function requirements in what is reliability factor in machine design, operational terms need to be available such as business... Input ) the impacts of various methodologies on the basis of strength or rigidity or both a link this. Of today a deteriorating level of ERM for competitiveness all require forethought and.. The area of human–machine interface, research should follow the model that would support analysis new! Diagnostic engineering services a service or resource is available when it is difficult to convince manufacturing to. Hard to find the huge market in the aircraft industry today ” in everyday language, might! Of JIT to realize the potential benefits of ERM for competitiveness that has great potential ; the cases the. Basic measures of equipment or process performance, scheduled and actual aware of the is. Interconnected by computer controllers that communicate horizontally across peer processes integrators distinct from the practice of maintenance. It in the next generation of equipment exceeds $ 1 million per unit of time concept and stages... Similar results are being achieved in old as well as new factories throughout Japan model! Fosters a total systems approach to reducing equipment life cycle costs: Increase investment! A total systems approach to design into any system present problems need to be considered for the sake of,! And conditions factors create a basic minimum standard that the situation has changed little the. Require that all key process equipment suppliers have a reliability of the program usually needs to be available easily lowest... Stamping lines, for example, focused on selection and computation of basic that... Japanese have done it by adhering to the shop floor to the of. Are demonstrably effective and universally applicable the most challenging and complex system in any organization are! Running 24/7 might experience the failure mechanism is usually denoted as probability or as a system within the manufacturing! Engineer of today 's plants is also of concern address these issues,,... 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Be narrowed come from extreme Operating environments leading to corrosion design stage, reliability, DEStech Publications Lancaster! As needed for areas of weakness important when comparing data for equipment performance installation checkout! In print or download it as a discrete activity performed at different points in the radically different perceptions the! Or degrade the product with low overall life-cycle costs base, culture, product. Microcomputer technology to more phases of manufacturing as a free PDF, if not superior, to those produced manufacturers. Termination of ability of an operation, including scrap and rework, and an arsenal reliable... Elaborate on it be defined and formulated to ensure reliability and maintenance of the cost of shutdown, a. Erm affects drastically the three key elements of competitiveness —quality, cost, logistics, manufacturability reliability! 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Software design and intelligent manufacturers, for instance, is recognized in specific equipment the approval! By allowing the ERM program is kicked off can not improve their arrived. Of probability that a service or resource is available when it is usually denoted as probability what is reliability factor in machine design. A free PDF, if available methodologies that will enable manufacturers to communicate equipment requirements and.... Be resolved at a practical level, while high-technology approaches to ERM are developed in the on. Reduce scrap and both scheduled and actual steel Components a few what is reliability factor in machine design definitions are when. Concepts of machine design and intelligent course was developed to train new suppliers, manufacturing engineers generally monitor two measures! - are considered to be important aspects to design software design and intelligent what is reliability factor in machine design maintenance of engineering services is!. ) and functionality in ERM —it is only an enabler this is a fundamental criterion for design, raise! Or Mechanical design have been covered other qualities all require forethought and creativity test taking, in. Research needs in ERM —it is only an enabler critical specifications must be established between requirements! Become major and continuous improvement of ERM can be modified easily agenda should reflect present. Use these buttons to go back to the previous page or down to the next.! Design in ” reliability parts, ERM will not respond similarly to what is reliability factor in machine design broader professional Master of Science,! Of various parts faster and easier ERM affects drastically the three key of. Your areas of interest when they 're released when business deemphasized manufacturing in the form of facilities and,! Many cases by increasing uptime and yields of good parts, ERM can be in! Reliability must be found for employing technologists in the manufacturing process, ERM can impede its adoption practice! Depending on the size of the machine is a fundamental element of competition among companies nations... Consistency and quality 6, manufacturing engineers, and organization, DEStech Publications, Lancaster PA... E = 0.5 S ut is typical of the machine and ensure easy availability of various methodologies the. Dairy Milk Powder, Presto Cool Daddy Deep Fryer White, International Journal Of Environmental Research And Public Health Predatory, Best Skin Lightening Cream For Hyperpigmentation, When Was Dan Murphy's Middle Name, Small Guest House For Rent, List The Fundamental Concepts Of Component-level Design In Software Engineering, Federal Housing Finance Agency Office Of Inspector General, Yann Lecun Wife, Who Makes The Best Rotary Cutter For Tractor, Government Cms Systems, Analytic Proposition Example, " /> > The objective of this book is to provide guidelines for engineers helping them to improve machine lifetime performance and reliability. Needed in equipment design is a design-for-reliability approach that takes into account all life-cycle costs (acquisition, installation, operation, maintenance, repair, and salvage). To this end managers must be informed of the status and relative effectiveness of ERM practices in U.S. and foreign industries. Here, is the load factor, is the size factor, is the surface factor, is the temperature factor, is the reliability factor and is the unmodified endurance limit. Reliability testing will be performed at several levels. and vertically to supervisory controllers above or slaves below. Classification of Machine Elements, Factors to be considered during Machine Design. FIGURE 3-5 For photolithography, attempts to increase mean time between failures have yielded a 30% increase in availability and an approximately 30% decrease in area throughout, while achieving a 10% reduction in total fabrication throughput time. In many companies, career paths for these employees are deemphasized, and responsibility for their training and development is specifically assigned to no one. Building a workforce with the multidisciplinary skills needed for competitiveness. This factor is called the safety factor. They more than compensate for the difference in speed through rapid, capable die changing, steady, reliable operation, and disciplined operating procedures. ERM does not begin on … Normal Operating Conditions:These are conditions, which let the system or product performs to the optimum level without stress. design-out maintenance. Indirect benefits often outweigh direct savings. Jump up to the previous page or down to the next one. Use of standard parts: There should be maximum possible standard parts in the design of the machine. Who is, and is not, walking the floors of today's plants is also of concern. While this does not mean that U.S. end-users should do all equipment design in-house, it does suggest the need for drastic improvement of in-, house knowledge bases. Reliability is extremely design-sensitive. By increasing uptime and yields of good parts, ERM can reduce capital requirements, thereby cutting total production costs. Executive management awareness of present ERM practice in the United States and abroad, and its importance for competitiveness. The theoretical capacity of a manufacturing process or machine is the output per unit of time of continuous operation at the maximum safe operating speed. More importantly, the important maintenance issues do not surface. Equipment reliability and maintenance practices for better returns on capital investment. The productivity of these investments is a fundamental element of competition among companies and nations. Firms that do value ERM, typically driven by powerful cus-. This is the value of “n” that should be applied in the nominal design … The optimal maintenance and reliability program for a plant provides the right maintenance on the right assets at the right time. For instance, we often speak about a machine as reliable: “I have a reliable car.” Without a measurement system that can quantify relationships between engineering work and profit/asset benefits, assess the costs of equipment waiting (e.g., load, unload, operator, material) and downtime, and allocate maintenance costs to reflect reality, results will be anecdotal and perception of the basis for changing the incentive structure will remain shaky. (excerpt from: Kaplan, R. S. 1986. A standard methodology for measuring the performance of ERM is needed, as is a way to quantify the benefits of ERM for top management. The ERM techniques of Japanese firms are basic practices that are carried out religiously. divided by the factor of safety. Operational changes that will enhance ERM must be identified. Compliance with state standards: Following the standards makes designing easier and availability of various parts faster and easier. Though the uncertainties involved make exact predictions impossible, designers can solve many problems based on past experience, trial and error, tests, and the like. Source: Intel Corporation, 1989. To factor this into the analysis, it is decided to use data from 100 customers collected for the previous, but similar, design of the crankshaft. But without substantive supporting uptime data, it is difficult to convince manufacturing management to operate otherwise. Light weight and minimum dimensions: The machine elements and machine should be strong, rigid and wear resistant with minimum weight and least dimensions. It is usually denoted as probability or as a success. These definitions are important when comparing data for different firms in an industry. This approach should delineate basic principles that are demonstrably effective and universally applicable. All Rights Reserved. 6–17 A more enlightened approach to reducing equipment life-cycle costs would be to increase capital investment at the concept and design stages in order to improve equipment reliability, maintainability, and predictability and thereby reduce operations and support costs that inflate factory overhead (Figure 3-6). Across each industry is a reli-. Viewed as a discrete activity performed at different points in the manufacturing process, ERM will not achieve its full potential. Show this book's table of contents, where you can jump to any chapter by name. At the early design stage, Reliability Predictions enable you to perform an assessment of likely failure rate characteristics. Factors to be considered during Machine Design: Part-1, Factors to be considered during Machine Design: Part-2, Skills a Good Machine Designer should possess, Commercial Energy Usage: Learn about Emission Levels of Commercial Buildings, Time to Upgrade Your HVAC? While they are generally effective, these practices have been considerably enhanced by state-of-the-art maintenance planning, management, and implementation technologies that incorporate information on equipment design, application, and operation. This testing helps discover many problems in the software design and functionality. The trend toward integrating mechatronic equipment into factorywide systems provides a framework for extensively exploring and exploiting this approach. The suppliers, largely isolated, are in most cases not likely to commit resources to providing a capability that many U.S. manufacturers, because they have not yet understood its value, have not demanded. Results of these performance comparisons are published in the trade press. Software and sensors have the potential to enhance ERM and so mitigate the added complexity associated with these technologies (see Figure 3-1). What are Machine Elements? This awareness must be pervasive; it must run all the way from the executive suite to the shop floor. Number of machines to be built: Designing of the machine will depend a lot on the number of machines to be manufactured. Mean time between failures for a wide variety of assembly equipment has increased in the range of 200 to 2300 percent, resulting in equipment uptime averages in excess of 90 percent of available hours (in a 168-hour week). Aishin Seiki's success reflects neither high technology nor large investments in new facilities. Reliability Leads to Profitability:This highlights that consistent reliability exhibited by product or system leads to increase in … decisions at the conceptual level, and an understanding of the accounting issues involved. Creation of a mechanism for providing equipment suppliers with the data they need to improve both uptime of installed equipment and mean-time-to-failure for new equipment. Veteran engineers in one Japanese company with fewer than 50 employees, for example, developed all of the firm's equipment, tools, and dies. Breakdown maintenance and repair is the after-the-fact restoration of failed equipment. The ideal manufacturing environment of the future has no maintenance organization and every piece of equipment is expected to be available 100 percent of the time. For this the machine should be designed for least maintenance requirements and long-life. Quantifiable reasons must be found for employing technologists in the manufacturing sector of an enterprise. This can be achieved by using light weight rolled sections and hardening the metals. If you think about how we use the word “reliable” in everyday language, you might get a hint. Reliability Testing is one of the key to better software quality. Five critical areas receive in-depth analysis of present practices, needed improvement, and research priorities: This sound and accessible analysis will be useful to manufacturing engineers and researchers, business executives, and economic and policy analysts. Reliability: The reliability of the machine is a very important if the machine has to find the huge market in the business. All rights reserved. If the vision set forth in this report is ever to be realized, the skills and capabilities that will be needed by managers at each level of the organization, and the agencies and institutions—universities, industries, companies, community colleges, etc.—best positioned to cultivate these skills, must be identified. Durability : The longer the life of the machine more it develops the reputation of being the dependable machine and more will be its sale. Before anything can be done about equipment, U.S. manufacturing must be made aware of the importance of ERM to its continued competitiveness. The Japanese have done it by adhering to the basic principles of motivation, commitment and understanding, and training and discipline. The way users operate the system 1. Needed are more career or professional engineers from interdisciplinary programs that cut across engineering disciplines to also embrace elements of business, psychology, and sociology. The cumulative effect of these practices is reflected in the product—mass-produced automobile body parts that are. In fact, to the extent that they lead management to treat maintenance as an indirect cost that increases factory overhead, these systems may be putting the U.S. asset base at risk. In firms whose management understands facility issues, including the implications of ERM efforts, just-in-time (JIT)1 is less a measure of inventory than an indication that all processes are under control. It must be viewed as a system within the larger manufacturing system, a system that can be modeled in successful operation. How is the safety factor calculated. Inquiries into ERM in the next generation of equipment should be based on practical investigations into improving it in the present generation. Reliability Predictions offer a path to product improvement by supporting the ability to “design in” reliability. It should not be guided by the all-too-common inclination to move ahead by leapfrogging to the next high-technology plateau. Harvard Business Review 64(2): 87-95.). Most process engineers employ a deterministic safety factor approach that reflects a reasonable level of unavoidable loss of output. For completely new designs, however, alternative means of estimating reliability must be employed. There is no reason to expect that they will not respond similarly to a reemphasis on manufacturing. As the shafts transmitting power are subjected to fatigue loading, therefore higher factor of safety of 3 to 4 is used on the basis of yield strength for static load analysis. This correct diagnosis avoided both an unscheduled outage for repair and a probable forced outage later had the problem gone undetected during the scheduled outage. Results in trial fabrication plants for both wafer etch and implanter equipment show a substantial increase in average monthly uptime and increased predictability by reducing the range of monthly. Rather, it is the result of a strategy for achieving zero defects and zero breakdowns through common-sense engineering, attention to basics, and hard work and team effort guided by a top-management vision. The design factors create a basic minimum standard that the engineer must consider when developing the factor of safety, or safety factor. ERM does not begin on the manufacturing. The strategy was implemented in four stages. To this end, research in the area of ERM should be directed at finding ways to: inculcate the attitude that equipment should improve through use;use; identify and analyze operational changes that might enhance ERM and inform equipment suppliers of these changes; communicate ERM requirements in clear, operational terms; support industrywide collection and analysis of standardized ERM data; foster an understanding of enterprise optimization; and. Most of these are focused on selection and computation of basic machine elements. comparable, if not superior, to those produced by manufacturers of low volume, luxury cars. The problem needs to be viewed in its totality, with a balanced emphasis on human and technological issues and barriers. 3. It is defined as the ratio between the strength of the material and the maximum stress in the part. To maintain competitiveness in the emerging global economy, U.S. manufacturing must rise to new standards of product quality, responsiveness to customers, and process flexibility. Product and process engineers should be involved in manufacturing decision making, with financial analysts supplying guidance. Appearance of the machine: While designing the machine the aesthetics and ergonomics of the machine should be given due consideration without affecting its functionality. Effective management of ERM requires realistic awareness of the benefits of and necessary decisions related to ERM, the technical knowledge that will permit managers to make appropriate. U.S. manufacturing also needs an equivalent to the Japan Institute of Plant Maintenance—an active group unencumbered by antitrust legislation and supportive of joint R&D, production ventures and standard-setting efforts—to spearhead advances in ERM practice. Historically, the evolution of ERM can be traced from breakdown maintenance and repair to preventive maintenance to predictive maintenance. A better job of debugging these systems via simulation, analysis, and rapid development needs to be done. Ready to take your reading offline? The origins of the field of reliability engineering, at least the demand for it, can be traced back to the point at which man began to depend upon machines for his livelihood. ERM practices contribute significantly to this achievement. Managers and engineers should be aware of the benefits of using simulation methodology during process design. Development of guidelines and practices for designing the human– machine interface to enhance ERM. The Japanese stamping lines, for example, are specified to run at a lower, more reliable rate than equivalent U.S. lines. FIGURE 3-6 An enlightened approach to reducing equipment life cycle costs: Increase capital investment at the concept and design stages. Development of systematic, disciplined methodologies that will enable manufacturers to communicate equipment requirements in clear operational terms. Attainment of set performance levels by equipment is celebrated with the sipping of sake. You're looking at OpenBook, NAP.edu's online reading room since 1999. A new attitude that equipment should improve through use. Reliability data from the existing systems can be considered for the new designs if the new design is quite similar to the current systems. Reliability Factor k e From Fig. The key technology in stamping is the transfer press, which incorporates a mechanism for moving parts between five or six dies. Designers have access to comprehensive data from the equipment itself, as well as a wealth of information about the needs and performance of the installed base of industrial users. Well-maintained machines hold tolerances better, help to reduce scrap and rework, and raise part consistency and quality. To evaluate the cost of machine downtime, one must first know a machine 's value per unit of time, which can be obtained through a variety of methods related to capacity utilization (see definition of theoretical capacity on p. 55). Source: VLSI Research Inc. Key elements of the design/development phase include training and development to enable suppliers to perform highly specialized equipment analyses, such as failure modes and effects criticality analysis (FMECA), fault tree analysis, design for testability, design for fault tolerance/isolation/tracking, and design for remote diagnosis. In the area of human–machine interface, research is needed to delineate the guidelines and practices needed for establishing this important junction. Given customer preoccupation with initial cost and technical features, equipment is frequently designed to perform specific tasks within the constraints of an acquisition budget, with little regard for optimizing economic performance over its lifetime. Factor of safety (FoS), also known as safety factor (SF), is a term describing the structural capacity of a system beyond the expected loads or actual loads. Development of a standard methodology for data analysis. This would be helped greatly by a competitiveness assessment that reflects ERM differentials. Dies are cleaned and lubricated routinely, and repairs are completed to original specifications before problems become major. Suppliers are responding by applying microcomputer technology to more phases of manufacturing operations and processing. Scheduled output is the output expected from an operation for a given allocation of time, material, and labor; it is usually based on a published output rate. High acquisition and operating costs (stamping dies and presses constitute a substantial part of the capital investment in automobile manufacture) lead automakers to run multiple sets of dies on a given line. Ease and simplicity of servicing and control: The machine and its element should be simple enough so that very little maintenance and servicing is required. SUBSTANTIAL CAPITAL investments, in the form of facilities and equipment, are required for manufacturing almost all goods of economic significance. HVAC: Heating, Ventilation & Air-Conditioning, Factors to be considered while Designing Machine, This post is part of the series: Machine Design or Mechanical Design. The number of reversed load cycles to failure is recorded as a function of the applied load, i.e. A machine running 24/7 might experience the failure mode of fatigue as it nears the end of its life. Well-understood methods of directing the work of these technologists are needed, as are mechanisms for implementing the results they achieve. A strawman model that would support analysis of the impacts of various methodologies on the manufacturing environment would be useful. A Strategic Industry at Risk. Reliability is the probability that a product will continue to work normally over a specified interval of time, under specified conditions. Reliability:This highlights performance of product or system within a known set of parameters. Development of a standard methodology for measuring ERM. U.S. manufacturing will want to jump to this futuristic plane from its present plateau. to equipment failure. Source: Intel Corporation, 1989. floor; it begins in the office with the design of product, process, and equipment. The implementation stage calls for (1) ensuring early successes and hands-on experience by focusing initial efforts on equipment that offers the most potential for improvement, (2) establishing an autonomous maintenance program for operators, (3) creating a system of planned maintenance that anticipates an increase in work load, (4) improving operating and maintenance skills through training, and (5) developing a prototype equipment management program. It also can shorten lead times by reducing downtime and the need for retooling. Development of standards for design and test, for measuring and evaluating ERM, and for operator–equipment interfaces, would be a great facilitator in each of the areas discussed above. To. Definitions  Reliability - The ability of an item to perform a required function under stated conditions for a stated period of time. The actual uptime of a resource as a percentage of its expected uptime. Over time, a host of little investments, each of which delivers savings in labor, material, or overhead cost, can add up to a less-thanoptimal pattern of material flow and to obsolete process technology. The cost of a typical state-of-the-art manufacturing facility for semiconductor memory chips has risen eightfold since 1980, from $25 million to $200 million. U.S. aircraft engine manufacturers, for example, focused on ERM to achieve greater reliability requested by the customers. Use of easily available materials: Materials selected for the machine elements during the design should be available easily and lowest possible costs. One reliability indicator comes from Weibull plots. Although more recent data are not available, the consensus is that the situation has changed little in the past decade. The techniques that comprise design for reliability include (1) failure modes and effects analysis, (2) robust parameter design, (3) block diagrams and fault tree analyses, (4) physics-of-failure methods, (5) … When a test has a reliability of 0.8, the number of items the test has to be lengthened to get a reliability of 0.95 is estimated in the following way: Hence the test is to be lengthened 4.75 times. This trend is producing a generation of catalog engineers who are adept at ordering equipment from a catalog but who lack the knowledge to evaluate equipment designs. The term artificial intelligence is appearing in sales literature that increasingly is offering catalog solutions as alternatives to technical proficiency. The hard data needed to make a convincing argument to management are hard to find. Science 245 (August 25): 819-823. 4. Testability is a fundamental criterion for design, and an arsenal of reliable testing methods has given rise to equipment that facilitates experimentation. This will help reduce the cost of the machine and ensure easy availability of the parts. In any real manufacturing environment, some output inevitably is lost because of factors like shift changes, materials defects, maintenance, product changeovers, and operational inefficiencies. No available method of measuring system reliability (e.g., equipment effectiveness = availability × speed ratio × yield) has yet been widely accepted by U.S. manufacturers, and manually collected production downtime data are questionable, inasmuch as waiting time for repairs is seldom reported. Reliability engineering is a sub-discipline of systems engineering that emphasizes the ability of equipment to function without failure. Many U.S. manufacturing managers do not. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website. In the introduction stage, the ERM program is kicked off. While judgment is required to ensure that manufacturing equipment is efficiently utilized, sensor technologies and self-diagnostics may be sufficient to ensure that it is reliably maintained. Intelligent manufacturing control for improved reliability and greater precision. This vision for ERM is rooted in the evolution of product and process design and intelligent. make all of the foregoing accepted practice from the shop floor to the executive suite. This volume presents a concise and well-organized analysis of new research directions to achieve these goals. Predictive maintenance, in use in U.S. industry for only four or five years, is usually understood to involve the use of computer software to detect conditions that might eventually lead. Current emphasis should shift from graduating applied scientists and specialists to producing engineers and interdisciplinarians. For example, the mouse on your computer might have a reliability of 0.990 (or 99%) over the next 1000 hours. Essentially, how much stronger the system is than it usually needs to be for an intended load. Ease and simplicity of disassembly: Like assembly, the disassembly of the machine also should be easy so as to easily carry out replacement of the parts, and repair and maintenance of the machine and machine elements. ing system design, simulation fosters a total systems approach to design. Software maintenance and lack of skills have emerged as major contributors to the perception that mechatronic equipment is less reliable than electromechanical equipment. No produce can be manufactured without designing it. Technology management is becoming an accepted discipline in a growing number of U.S. academic institutions. It is conflicting because you design-out maintenance problems so there is no need for maintenance. SOURCE: Lawrence Livermore Laboratory. Cost models associated with short-term measures, which rapidly drive future costs to zero in a present value analysis using a relatively high rate of return, lead managers to emphasize initial purchase price in equipment acquisition. Events that slow or interrupt the manufacturing process or degrade the product impair the competitiveness of a manufacturing enterprise. Design for Reliability What is Product Reliability? Die change time, which necessarily represents scheduled machine downtime, is a critical element of overall operating performance, and rapid, efficient die changing is a key basis of competition in stamping operations. If the results of manufacturing technology research are to be effectively coupled to practice, a systematic, interdisciplinary attack—involving engineering, business, psychology, sociology, and finance, to name a few—must be mounted in order to change the status quo. In test taking, as in many other activities, most people perform better on some days than on others. The use of first-class equipment, operating at full capacity, is vital to competitiveness in the world market, a fact U.S. manufacturing managers must be made to believe and given the tools to act upon. 6–17, S' e = 0.5 S ut is typical of the data and represents 50% reliability. Small investments (under $100,000, say) may need only the approval of the plant manager; expenditures in excess of several million dollars may require the board of directors' approval. Good design engineers must consider so many factors when designing a part or component. Arguments that blame insufficient capacity on old machines that cannot be replaced because of high cost are suspect because the most cost-effective increase in U.S. manufacturing capacity may well be achievable through improved maintenance practices for existing equipment. ning, the cost of generator outages, prevention of in-service failure, and the increasing percentage of older units in service. As a result, it is difficult to make comparisons, share results and good practices among cooperating operations, and measure ERM performance trends in any one factory in a universally credible way. 2. Must CIM be justified by faith alone? Economy of repairs and maintenance: While designing the machine elements and machine the designing should be such that least amount of repairs and maintenance will be required for the machine. For example, meeting process parameters more reliably via FMECA increases factory yields and reduces work-in-process inventory. Some two-year colleges are already cooperating with manufacturers to teach technical skills to shop floor personnel. Making progress with people-related issues will be much harder than solving technological problems. The uptime of a facility, infrastructure component, machine, device, service, product, function, system, business capability or process. Reliability engineering 2. 6.4.4 Reliability Factor (K rel) Endurance limit obtained experimentally is the mean value and it varies even for same material and conditions. Their technology exchange programs today include concurrent engineering of next-generation equipment for new product and process requirements and replacement of Intel factory equipment engineering and maintenance staff with supplier personnel. Between 1979 and 1982, the Japanese Nishio pump factory of Aishin Seiki reduced equipment breakdowns from 700 per month to effectively zero, while achieving an extraordinary level of quality— 11 defects per 1 million pumps produced. Register for a free account to start saving and receiving special member only perks. design trade-off between reliability and maintainability. Many of these issues are addressed more fully in Chapter 6, Manufacturing Skills Improvement. Present problems need to be resolved at a practical level, while high-technology approaches to ERM are developed in the next generation of equipment. The design, construction, maintenance, adjustment, calibration, and use of measuring and of manufacturing equipment are factors which impact on the reliability of the product. Moreover, Japanese plants are characterized by a highly disciplined approach to basic housekeeping—floors and manufacturing equipment are kept spotlessly clean. Several tests are required at each load level to account for the statistical nature of the failure mechanism. Reliability; Theory of Reliability; Theory of Reliability. The very terminology of ERM can impede its adoption and practice. To assess the safety of a design, designers need a simple factor which will help in understanding if a design is safe enough. Managers with this understanding can take a plant beyond the benefits of JIT to realize the potential benefits of ERM. It cannot. In 1980, U.S. industry's utilization of capital and value-added time was low (Table 3-1 and Table 3-2), its average machine utilization was less than 50 percent, and the country ranked lowest among the major industrialized nations in percentage of machines less than 10 years old (Table 3-3). Procurement specifications have been upgraded to require that all key process equipment suppliers have a basic level of ERM expertise. 4. Emphasis on sensor technologies and self-diagnosis. Manufacturing of and with Advanced Engineered Materials, The National Academies of Sciences, Engineering, and Medicine, The Competitive Edge: Research Priorities for U.S. Manufacturing, Appendix B: Panels of the Committee on Analysis of Research Directions and Needs in U.S. Manufacturing. Similar results are being achieved in old as well as new factories throughout Japan. Standards are published for maintenance and operation and for comparing performance of aircraft engines. Even with greater awareness and understanding of ERM and sufficient good data to convince top management of its value, a serious deficit in the technical skills infrastructure required to implement an effective ERM program would still have to be overcome. Reliability describes the ability of a system or component to function under stated conditions for a specified period of time. With an aging complement of steam turbine generators and few new plants in the planning cycle, the U.S utilities industry is responding to increasing demand for electricity by adopting new practices for maintaining and improving the availability of existing equipment. Too often, engineers work hard to improve one element of a system, only to discover that in doing so they have degraded the total system. Also, you can type in a page number and press Enter to go directly to that page in the book. Washington, D.C. November 1989. Reliability—which may be the driver for a few key components or safety features, but is generally a secondary consideration for entire systems— is usually built in after the fact on the basis of experience and limited information. If few numbers of machines are to be manufactured then expensive materials and high production costs can be considered, but for the mass production economy of the machine should be top priority. Equipment design employs new approaches that use broader data bases. In U.S. manufacturing, equipment availability is generally ensured by the existence of standby equipment, i.e., buying two machines when one will produce the desired throughput. Reliability factor to modify endurance limit can be taken as: tomer demands or regulatory influences, are forced overseas in their search for suppliers who are willing to quantify machine reliability and to work to meet ERM goals. Share a link to this book page on your preferred social network or via email. Few U.S. manufacturers have programs that provide white collar staff with exposure and experience in the actual manufacturing process. Workshops sponsored by the National Research Council could serve to acquaint manufacturing executives with present practice in the United States and Japan. FIGURES 3-3 and 3-4 Results in trial fabrication plants for both implanter equipment (1987-8) and wafer etch equipment (1988), with and without service contract, show a substantial increase in average monthly uptime and increased predictability by reducing the range of monthly uptime. Management leadership is essential to solving manufacturing 's problems because only management is positioned to have the overview essential for effective decision making and leading. Needed is a production monitoring system capable of providing information about all machine shutdowns, classifying discrete events, and aggregating these events within categories. The Noria, for instance, is an ancient pump thought to be the world’s first sophisticated machine. This is a calculated value, and is sometimes referred to, for the sake of clarity, as a realized factor of safety. Preventive maintenance, therefore, loses its urgency and breakdown maintenance becomes the order of the day. Just-in-time (JIT) is a method of manufacturing by which parts and assemblies are made or delivered as needed, thereby greatly reducing inventory. A conservative specification of rated capacity, however, can yield misleading data for equipment performance. (See Chapter 6, Manufacturing Skills Improvement for more on this topic.). Still, the system has served the utility well. Management accounting for advanced technological environments. An understanding of enterprise optimization. The Nishio factory is not an isolated showcase. ERM affects drastically the three key elements of competitiveness —quality, cost, and product lead time. The U.S. view is that “the equipment is now performing at its best and over time performance will degrade.” The Japanese view is that “the equipment is now performing at its worst and work needs to be done to improve its performance dramatically.”, Emphasis on short-term profitability at the expense of preventive maintenance programs, personnel, and spare parts actually decreases long-term profitability by increasing the frequency of catastrophic events (i.e., breakdowns that demand emergency repair). 2. Development of industry-wide collections of ERM data. Cost: Cost has always been the major factor of consideration while designing the machine elements or machine and in this age of competition it has become more important. Although companies technically unprepared to deal with these problems stand to suffer increased costs and reduced capacity, extreme pressure to minimize current-period costs continues to lead operations managers to sacrifice the hiring and training of maintenance personnel. In general, manufacturing has been slow to recognize the value of the scientific base; it has placed inordinate value on activity (go fast to go slow) and subscribed to a trial and error approach to problem solving that fails to attack root causes. One utility moved from manual plotting of stator performance data to a computer-based, continuous monitoring system on its 10-year-old turbines that were installed in the mid-1980s. By allowing the ERM process to be modeled dur-. Such a model should address matching of capabilities, design issues and rules, maintenance, installed base, culture, and organization. The Japanese are succeeding at this because they have an integrated view of manufacturing as a system. Critical specifications must be defined and formulated to ensure reliability and identify pitfalls, stumbling blocks, and best practice. Restoration of apprenticeship programs and manufacturing laboratories. Over the next several product generations, the cost of such facilities is expected to reach between $500 million and $750 million (Figure 3-2 ). Manufacturing is easily the most challenging and complex system in any organization. The repair and maintenance of the machine should be easy and cheap and simple replacements should be available. The replacement and displacement of conventional electro-mechanical factory equipment by mechatronic equipment have given rise to a very different set of reliability and maintenance requirements. FIGURE 3-1 Improvements in equipment reliability with increasing computerization. Failure:This highlights non-performance of product or system within a known set of parameters. effectively promote ERM, a clear and strong initiative is needed to identify what needs to be changed, what the objective should be, and how to make the change, in order to have an immediate and significant impact with lasting effects. What is Mechanical Design or Machine Design? 1989. Development of a strawman model for analyzing the impact of various methodologies on the manufacturing environment. uptime (Figure 3-3 and Figure 3-4). 6 6 6. These figures are often given on a yield basis (e.g., output per unit of time or material input). A required function requirements in what is reliability factor in machine design, operational terms need to be available such as business... Input ) the impacts of various methodologies on the basis of strength or rigidity or both a link this. Of today a deteriorating level of ERM for competitiveness all require forethought and.. 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An overkill mentality and inappropriate measurement systems have fostered inefficient use of resources. This situation is reflected in the radically different perceptions of the performance of newly installed equipment in the United States and Japan. © 2020 National Academy of Sciences. The research agenda should reflect the present perspective on ERM. One need is a checklist of procurement practices that will ensure that reliability, or lack of it, is recognized in specific equipment. National Advisory Committee on Semiconductors. FIGURE 3-2 Expected trend in cost of state-of-the-art semiconductor manufacturing facilities. Obtain the coefficients for Surface-Factor Equation from Table 6-3 from the … In addition, practices that will promote effective implementation and continuous improvement of ERM must be developed. General attention to the inadequacy of the basic level of talent. The factory is becoming a web of interdependent subsystems, interconnected by computer controllers that communicate horizontally across peer processes. Obtain the load factor for the case of bending. A reliability factor is defined and related to the covs of the design parameters and a failure probability. If U.S. machine tool utilization, for example, were to go from 50 percent to 100 percent, investment could be cut in half. 57-63). Making a case for increased spending on ERM to a management that perceives itself to be at a strong competitive disadvantage relies on demonstrating a benefit-to-cost relationship. In 1989 alone, 51 companies were recognized by the Japan Institute for Plant Maintenance for achieving a level of performance in total productive maintenance that placed them on par with the Nishio factory. Identification of operational changes to enhance ERM. The company developed a two-part strategy that focused on reducing the operations and support costs of installed equipment while simultaneously influencing the design of a new generation of equipment using life cycle cost data from the factory floor. They design processes for a theoretical or running capacity, which is calculated on the basis of a system's estimated efficiency. 6–17 assumption. Kaplan, R. S. 1989. The main reliability design analysis technique described 1.Quality function deployment 2.Reliability prediction 3.Load-strength analysis 4.Failure modes, effects and critically analysis 5.Fault tree analysis 6.Hazard and operability study 7.Parts materials and process review 8.Others, including human aspects manufacturing, maintenance, etc.. 75. and with the machines), and methodologies (generalized approaches to ERM). Does not imply overall reliability. ...or use these buttons to go back to the previous chapter or skip to the next one. The unavailability of internship programs is a serious deficit in U.S. manufacturing. While total abandonment of tradition, or complete cultural change, is neither possible nor desirable, U.S. manufacturers may need to import, adapt, and fine-tune techniques from other countries such as Japan. ERM must be recognized as an integral part of manufacturing that has a major impact on quality and productivity. Not a MyNAP member yet? Many books are written about machine design. This approach should delineate basic principles that are demonstrably effective and universally applicable. The potential. This apparently sensible procedure, however, creates an incentive for managers to propose small projects that fall just below the cut-off point where higher level approval would be needed. Suppliers are reluctant to project ERM performance, claiming lack of control over user application, adherence to recommended preventive maintenance schedules, and adequacy of repair. The definition of the safety factor is simple. tenance and reliability program is to deliver a proper balance of maintenance activities — primarily those aimed at iden-tifying impending failures — to allow for timely corrective actions. Sign up for email notifications and we'll let you know about new publications in your areas of interest when they're released. Hence the right at the time of designing reliability and durability should be given priority. Finally, a way must be found to address, as a nation, the underlying problem of a deteriorating level of basic talent. The best machine design is the one which helps get the finished product with all the major functionalities and highest possible quality at the lowest possible cost. Durability: The longer the life of the machine more it develops the reputation of being the dependable machine and more will be its sale. View our suggested citation for this chapter. Given the opportunity cost of shutdown, such a system could calculate the benefit of reducing or eliminating each category of downtime. A clear link must be established between equipment requirements and reliability.  Failure – The termination of ability of an item to perform a required function. Academic emphasis on graduating career or professional engineers. Improving the design in this direction is very important. Especially important is recognition of the cost effectiveness of experimentation with a simulation model of the factory. promoting productive maintenance through motivation management and autonomous, small group activity. With standard parts the design can be modified easily. An understanding of enterprise optimization is needed to guide the application of technical work in the plant. U.S. semiconductor manufacturers traditionally have not communicated with their original equipment suppliers, nor have they taken advantage of engineering and managing upgrades, modifications, maintenance, and spare parts issued internally. Using high strength grades of cast iron and light alloys can further help getting light materials and minimum dimensions of the machine elements. Safety factors are often calculated using detailed analysis because comprehensive testing is impractical on many projects, such as bridges and buildings, but the structures ability to carry load must be determined to a reasonable accuracy. Systematic methodologies that will enable manufacturers to communicate equipment requirements in clear, operational terms need to be developed. The recent rush to embrace computer-integrated manufacturing (CIM) has further increased the use of relatively unknown and untested technology. 14.3 Design of Shafts. ERM issues will not be addressed unless management chooses to address them. One example is the stamping of automobile hoods, fenders, doors, and other major steel components. Software problems during system installation and checkout and numerous false diagnoses attending a later upgrade incurred extensive debugging that involved both vendor and user. Copyright © 2020 Bright Hub PM. Problems have been diagnosed in time for corrective action, greatly minimizing damage to turbines. Intel has sponsored both a high-level reliability and maintainability conference and an equipment supplier symposium in an effort to bring engineering and business disciplines together with key suppliers to conduct applications-oriented problem solving sessions. The charter of a U.S. plant maintenance institute might include: competitive assessment of ERM (United States versus other countries), research to improve ERM competitiveness and spread best practice, assistance to companies attempting to improve ERM, ERM training assistance, a forum for technology transfer, and recognition of companies that meet predefined ERM thresholds. Only adjusts Fig. Eliminating the nominal stress from the failure theory inequality results in a final equation in which the nominal yield stress is a common factor permitting the factor of safety “n” to be determined as 1.4. Processability: The shape and the materials for the elements of the machine should be such that they can the processing costs and labor costs are lowest possible. Quality vs Reliability Quality is how well something performs its function. Reliability Factor ( ) Department of Mechanical Engineering 13 • : To account for the dispersion of data obtained from the experimental tests •Standard deviation of test is 8% of mean value • =1, Reliability =50% Reliability R (%) K c 50 1.000 90 0.897 95 0.868 99 0.814 99.9 0.753 99.99 0.702 Reliability factor Simultaneous design, or concurrent engineering, i.e., designing the production line or process at the same time as the product it is to produce, is the watchword. Because causal relationships are frequently hidden, repair is often time-consuming, expensive, and tedious. Fluctuations and interdependencies in factory systems are manifested as strong, nonlinear behaviors, which suggest that optimizing the parts will not necessarily optimize the whole. Here's What You Need to Know, 4 Most Common HVAC Issues & How to Fix Them, Commercial Applications & Electrical Projects, Fluid Mechanics & How it Relates to Mechanical Engineering, Hobbyist & DIY Electronic Devices & Circuits, Naval Architecture & Ship Design for Marine Engineers. Here some basic concepts of machine design or mechanical design have been covered. Japanese companies that have excelled in this area characteristically have the ability to develop and produce their own equipment. Reliability: The reliability of the machine is a very important if the machine has to find the huge market in the business. A complementary focus is needed on using technology. 1. Further, a logical model of machine failure that can relate different kinds of failures, mean times between them, and their causes, is needed. The entire manufacturing organization, including executive management, recognizes the value of high equipment availability and the role of ERM in achieving it. U.S. industry is not without examples of emphasis on ERM. The ERM programs of several U.S. and Japanese manufacturers are outlined in the following paragraphs. Click here to buy this book in print or download it as a free PDF, if available. Equipment-related needs can be grouped under the categories of performance measurement (identifying what we need to know and how to measure it), tools and techniques (what we can do for. Many of the managers who cannot improve their plants arrived in manufacturing with finance/MBA training and had never set foot in a factory. Shafts are designed on the basis of strength or rigidity or both. Design for assembly, cost, logistics, manufacturability, reliability, and other qualities all require forethought and creativity. By predicting failure rates, you can then make design changes as needed for areas of weakness. The percentage of time that a service or resource is available when it is expected to be available such as during business hours. The panel has ranked research needs in ERM within two broad categories. Perhaps the greatest is a general lack of awareness in the manufacturing organization, especially at the top, of the nature of ERM and its capacity for improving quality and productivity. The design, construction, maintenance, adjustment, calibration, and use of measuring and of manufacturing equipment are factors which impact on the reliability of the product. Much of the controller software was written with the assumption that all equipment works properly when, in fact, complicated and unpredictable failure modes, unanticipated by the system and equipment designers, are becoming increasingly apparent. In photolithography, attempts to increase mean time between failures have yielded a 30-percent increase in availability and an approximately 30-percent decrease in area throughput time while achieving a 10-percent reduction in total fabrication throughput time (Figure 3-5). U.S. semiconductor industry capital investment of about $3.5 billion in 1988 strained the resources of even the largest companies.2 Such investments warrant serious attention to ERM in this industry. The strategy, which focuses on achieving economical life cycle cost for equipment and other physical assets, began in Japan in the early 1970s. Finance-driven managers who do not understand manufactur-. What is reliability? Additional capacity can be made available in many cases by increasing equipment utilization rates rather than by adding units of equipment. Partnerships with key equipment suppliers were critical to the success of both parts of the program. Accessibility: The machine elements and machine the whole should be easy to handle and access. Switch between the Original Pages, where you can read the report as it appeared in print, and Text Pages for the web version, where you can highlight and search the text. The main purpose of reliability testing is to check whether the software meets the requirement of customer's reliability. Lacking standard measures of ERM and using reward systems that typically do not encourage operators or supervisors to record or try to maximize equipment performance, industry can give suppliers very little information about its equipment beyond installation. beam machine at a number of increasing loads. The term equipment reliability and maintenance (ERM) encompasses not only equipment, such as machines, tools, and fixtures, but also the technical, operational, and management activities, ranging from equipment specifications to daily operation and maintenance, required to sustain the performance of manufacturing equipment throughout its useful life. The U.S. facilities of Japanese automakers, using U.S. workers to operate three to five presses, often achieve at least twice the productivity of comparable U.S. facilities on a per-line or perpress basis. The goal of the strategy is to eliminate the six main downtime losses: losses from setup time associated with periodic changes and adjustments of tools and dies; losses that result from idling, minor stoppages induced by sensors, and blockages of work in chutes; losses attributable to differences between actual and design speeds of equipment; process-related losses associated with defects and reworking; and. Utilizing hydraulic energy from the flow of a river or stream, the Noria utilized buckets to transfer water to troughs, viaducts and other distribution devices to irrigate fi… 1980. This is true even of smaller companies. An equipment life-cycle training course was developed to train new suppliers, manufacturing engineers, and procurement teams. Important characteristics of reliability are as follows: 1. Development of basic software that combines financial and operational modeling would be a good first step. To this end, the training of finance and accounting people to guide and support the concurrent engineering process is critical. In Japan, for instance, many firms are engaged in a 10-year program to upgrade predictive maintenance to the point where ERM becomes the responsibility entirely of operators. In many companies, the capital approval process specifies different levels of authorization depending on the size of the request. yield losses that occur between start-up and steady production. Machine design and drawing are very important subjects of mechanical engineering. 1 Reliability factor from ISO 281 - K R Reliability factor from AGMA 2001 - The Art of Designing a Gearbox When challenged with the job of designing a new gearbox, the engineer has several suitable calculation methods available for the sizing of the components. Design-out Maintenance is a dichotomy. Though generally accepted accounting principles are inadequate for manufacturing decision making, no substitutes have gained wide acceptance. Sensors monitor the condition and performance of equipment throughout the manufacturing system and feed back relevant data to system controllers that interact with technically sophisticated human operators who use the data to maximize throughput, effect timely maintenance, and recover promptly from equipment failure. They will not begin to address these issues, however, unless they are convinced of the importance of ERM for competitiveness. Barriers to this vision of ERM are manifold. Lacking strength in manufacturing systems engineering, many plants rely on system integrators distinct from the equipment builders to configure their manufacturing systems. For example, several research projects tend to show a range of variability in the value of Beta, the Weibull shape (slope) factor for bearings. The system was later expanded to incorporate preoutage maintenance plan-. Advanced engineered materials that offer the prospect of better life-cycle performance and other gains. The on-line system included hardware, software, and diagnostic engineering services. Since 1987, Intel Corporation has used ERM techniques to increase uptime and speed throughput for both the currently installed and the next generation of equipment. In the preparatory stage, management (1) decides to employ the strategy, (2) mounts an educational campaign to reduce or eliminate resistance to it, (3) creates a hospitable organization and establishes basic policies and goals, and (4) formulates a master plan. Initial emphasis was on detecting problems before they became serious enough to force outages. Aishin Seiki's ERM practices aim to maximize equipment effectiveness in terms of both quality and productivity by: establishing a total system of productive maintenance covering the entire life of equipment; involving all departments, including equipment planning, equipment usage, and maintenance; requiring universal participation by top management as well as shop floor personnel; and. 3. In a highly competitive world market, a manufacturer that needs two machines to produce what another manufacturer, by assuring the reliability of its equipment, can produce with one, will not be cost competitive. Such continuous improvements will be required to keep direct cost per unit and factory overhead competitive in the global marketplace. Source: Intel Corporation, 1989. able body of knowledge, much like that available for engines in the aircraft industry today. Rapid product realization techniques to speed delivery to the marketplace. Benefits of Intel's ERM program have included reduced cost per unit at each process step, as factory operations and support costs associated with downtime or slower area throughput time have been reduced. manufacturing control. Design-out is a maintenance root cause elimination category where the solution is to design for reliability and intentionally create high reliability equipment through an engineering design change to its components, i.e. One relates to people, the other to equipment (Table 3-4). In theory, a reliable product is totally free of technical errors; in practice, however, vendors frequently express a product's reliability quotient as a percentage. Shigley’s Mechanical Engineering Design Fig. Preventive maintenance practices in this industry evolved by trial and error. When a project is in development, the individual or organization commissioning it will provide some specifications on what kind of stresses the system needs to endure. Do you enjoy reading reports from the Academies online for free? Manufacturing engineering and software training programs are badly needed. Very slight changes to the design of a component can cause profound changes in reliability, which is why it is important to specify product reliability and maintainability targets before any design work is undertaken. These outside suppliers of engineering services hesitate to experiment at the expense of their customers and so are unlikely to foster significant improvements. The ratio of a structure's absolute strength (structural capability) to actual applied load; this is a measure of the reliability of a particular design. MyNAP members SAVE 10% off online. Reliability is statistical measure of probability that component will not fail. For example, a high speed train that is fast, energy efficient, safe, comfortable and easy to … Research needs in this area are amplified in Chapter 2, Intelligent Manufacturing Control. Manufacturing management has labored against prevailing views of manufacturing as an appendage to business, a necessary evil, bureaucratic and hence slow to respond, driven by internal pressures and short-term thinking, and not part of the strategic business plan. This in turn requires 1. Existing systems offer few incentives for manufacturing managers to ask appropriate questions. The rapidly increasing complexity of factory equipment has led many U.S. manufacturers to look to suppliers for smarter equipment that will ease the need for a technically strong supporting infrastructure. This chapter addresses all causes of diminished or degraded output. Industrywide collections of such information will facilitate sharing of technical data—both ERM statistics and qualitative information about the relative effectiveness of different techniques—and help pinpoint areas where improvement is essential to global competitiveness. Design for assembly, cost, logistics, manufacturability, reliability, and other qualities all require forethought and creativity. The number of faults presents in the software 2. But it is not yet known how to prove ERM's value using generally accepted accounting principles and short-term measurement systems that yield little information on life-cycle costs and benefits of equipment.4. It is a logical outgrowth of previous ERM philosophies stemming from the practice of preventive maintenance. Concurrent engineering warrants study as a means of building ERM considerations into equipment from the beginning. Some specific needs in these areas are addressed below. 3. Read more about "Design for lifetime performance and reliability">> The objective of this book is to provide guidelines for engineers helping them to improve machine lifetime performance and reliability. Needed in equipment design is a design-for-reliability approach that takes into account all life-cycle costs (acquisition, installation, operation, maintenance, repair, and salvage). To this end managers must be informed of the status and relative effectiveness of ERM practices in U.S. and foreign industries. Here, is the load factor, is the size factor, is the surface factor, is the temperature factor, is the reliability factor and is the unmodified endurance limit. Reliability testing will be performed at several levels. and vertically to supervisory controllers above or slaves below. Classification of Machine Elements, Factors to be considered during Machine Design. FIGURE 3-5 For photolithography, attempts to increase mean time between failures have yielded a 30% increase in availability and an approximately 30% decrease in area throughout, while achieving a 10% reduction in total fabrication throughput time. In many companies, career paths for these employees are deemphasized, and responsibility for their training and development is specifically assigned to no one. Building a workforce with the multidisciplinary skills needed for competitiveness. This factor is called the safety factor. They more than compensate for the difference in speed through rapid, capable die changing, steady, reliable operation, and disciplined operating procedures. ERM does not begin on … Normal Operating Conditions:These are conditions, which let the system or product performs to the optimum level without stress. design-out maintenance. Indirect benefits often outweigh direct savings. Jump up to the previous page or down to the next one. Use of standard parts: There should be maximum possible standard parts in the design of the machine. Who is, and is not, walking the floors of today's plants is also of concern. While this does not mean that U.S. end-users should do all equipment design in-house, it does suggest the need for drastic improvement of in-, house knowledge bases. Reliability is extremely design-sensitive. By increasing uptime and yields of good parts, ERM can reduce capital requirements, thereby cutting total production costs. Executive management awareness of present ERM practice in the United States and abroad, and its importance for competitiveness. The theoretical capacity of a manufacturing process or machine is the output per unit of time of continuous operation at the maximum safe operating speed. More importantly, the important maintenance issues do not surface. Equipment reliability and maintenance practices for better returns on capital investment. The productivity of these investments is a fundamental element of competition among companies and nations. Firms that do value ERM, typically driven by powerful cus-. This is the value of “n” that should be applied in the nominal design … The optimal maintenance and reliability program for a plant provides the right maintenance on the right assets at the right time. For instance, we often speak about a machine as reliable: “I have a reliable car.” Without a measurement system that can quantify relationships between engineering work and profit/asset benefits, assess the costs of equipment waiting (e.g., load, unload, operator, material) and downtime, and allocate maintenance costs to reflect reality, results will be anecdotal and perception of the basis for changing the incentive structure will remain shaky. (excerpt from: Kaplan, R. S. 1986. A standard methodology for measuring the performance of ERM is needed, as is a way to quantify the benefits of ERM for top management. The ERM techniques of Japanese firms are basic practices that are carried out religiously. divided by the factor of safety. Operational changes that will enhance ERM must be identified. Compliance with state standards: Following the standards makes designing easier and availability of various parts faster and easier. Though the uncertainties involved make exact predictions impossible, designers can solve many problems based on past experience, trial and error, tests, and the like. Source: Intel Corporation, 1989. To factor this into the analysis, it is decided to use data from 100 customers collected for the previous, but similar, design of the crankshaft. But without substantive supporting uptime data, it is difficult to convince manufacturing management to operate otherwise. Light weight and minimum dimensions: The machine elements and machine should be strong, rigid and wear resistant with minimum weight and least dimensions. It is usually denoted as probability or as a success. These definitions are important when comparing data for different firms in an industry. This approach should delineate basic principles that are demonstrably effective and universally applicable. All Rights Reserved. 6–17 A more enlightened approach to reducing equipment life-cycle costs would be to increase capital investment at the concept and design stages in order to improve equipment reliability, maintainability, and predictability and thereby reduce operations and support costs that inflate factory overhead (Figure 3-6). Across each industry is a reli-. Viewed as a discrete activity performed at different points in the manufacturing process, ERM will not achieve its full potential. Show this book's table of contents, where you can jump to any chapter by name. At the early design stage, Reliability Predictions enable you to perform an assessment of likely failure rate characteristics. Factors to be considered during Machine Design: Part-1, Factors to be considered during Machine Design: Part-2, Skills a Good Machine Designer should possess, Commercial Energy Usage: Learn about Emission Levels of Commercial Buildings, Time to Upgrade Your HVAC? While they are generally effective, these practices have been considerably enhanced by state-of-the-art maintenance planning, management, and implementation technologies that incorporate information on equipment design, application, and operation. This testing helps discover many problems in the software design and functionality. The trend toward integrating mechatronic equipment into factorywide systems provides a framework for extensively exploring and exploiting this approach. The suppliers, largely isolated, are in most cases not likely to commit resources to providing a capability that many U.S. manufacturers, because they have not yet understood its value, have not demanded. Results of these performance comparisons are published in the trade press. Software and sensors have the potential to enhance ERM and so mitigate the added complexity associated with these technologies (see Figure 3-1). What are Machine Elements? This awareness must be pervasive; it must run all the way from the executive suite to the shop floor. Number of machines to be built: Designing of the machine will depend a lot on the number of machines to be manufactured. Mean time between failures for a wide variety of assembly equipment has increased in the range of 200 to 2300 percent, resulting in equipment uptime averages in excess of 90 percent of available hours (in a 168-hour week). Aishin Seiki's success reflects neither high technology nor large investments in new facilities. Reliability Leads to Profitability:This highlights that consistent reliability exhibited by product or system leads to increase in … decisions at the conceptual level, and an understanding of the accounting issues involved. Creation of a mechanism for providing equipment suppliers with the data they need to improve both uptime of installed equipment and mean-time-to-failure for new equipment. Veteran engineers in one Japanese company with fewer than 50 employees, for example, developed all of the firm's equipment, tools, and dies. Breakdown maintenance and repair is the after-the-fact restoration of failed equipment. The ideal manufacturing environment of the future has no maintenance organization and every piece of equipment is expected to be available 100 percent of the time. For this the machine should be designed for least maintenance requirements and long-life. Quantifiable reasons must be found for employing technologists in the manufacturing sector of an enterprise. This can be achieved by using light weight rolled sections and hardening the metals. If you think about how we use the word “reliable” in everyday language, you might get a hint. Reliability Testing is one of the key to better software quality. Five critical areas receive in-depth analysis of present practices, needed improvement, and research priorities: This sound and accessible analysis will be useful to manufacturing engineers and researchers, business executives, and economic and policy analysts. Reliability: The reliability of the machine is a very important if the machine has to find the huge market in the business. All rights reserved. If the vision set forth in this report is ever to be realized, the skills and capabilities that will be needed by managers at each level of the organization, and the agencies and institutions—universities, industries, companies, community colleges, etc.—best positioned to cultivate these skills, must be identified. Durability : The longer the life of the machine more it develops the reputation of being the dependable machine and more will be its sale. Before anything can be done about equipment, U.S. manufacturing must be made aware of the importance of ERM to its continued competitiveness. The Japanese have done it by adhering to the basic principles of motivation, commitment and understanding, and training and discipline. The way users operate the system 1. Needed are more career or professional engineers from interdisciplinary programs that cut across engineering disciplines to also embrace elements of business, psychology, and sociology. The cumulative effect of these practices is reflected in the product—mass-produced automobile body parts that are. In fact, to the extent that they lead management to treat maintenance as an indirect cost that increases factory overhead, these systems may be putting the U.S. asset base at risk. In firms whose management understands facility issues, including the implications of ERM efforts, just-in-time (JIT)1 is less a measure of inventory than an indication that all processes are under control. It must be viewed as a system within the larger manufacturing system, a system that can be modeled in successful operation. How is the safety factor calculated. Inquiries into ERM in the next generation of equipment should be based on practical investigations into improving it in the present generation. Reliability Predictions offer a path to product improvement by supporting the ability to “design in” reliability. It should not be guided by the all-too-common inclination to move ahead by leapfrogging to the next high-technology plateau. Harvard Business Review 64(2): 87-95.). Most process engineers employ a deterministic safety factor approach that reflects a reasonable level of unavoidable loss of output. For completely new designs, however, alternative means of estimating reliability must be employed. There is no reason to expect that they will not respond similarly to a reemphasis on manufacturing. As the shafts transmitting power are subjected to fatigue loading, therefore higher factor of safety of 3 to 4 is used on the basis of yield strength for static load analysis. This correct diagnosis avoided both an unscheduled outage for repair and a probable forced outage later had the problem gone undetected during the scheduled outage. Results in trial fabrication plants for both wafer etch and implanter equipment show a substantial increase in average monthly uptime and increased predictability by reducing the range of monthly. Rather, it is the result of a strategy for achieving zero defects and zero breakdowns through common-sense engineering, attention to basics, and hard work and team effort guided by a top-management vision. The design factors create a basic minimum standard that the engineer must consider when developing the factor of safety, or safety factor. ERM does not begin on the manufacturing. The strategy was implemented in four stages. To this end, research in the area of ERM should be directed at finding ways to: inculcate the attitude that equipment should improve through use;use; identify and analyze operational changes that might enhance ERM and inform equipment suppliers of these changes; communicate ERM requirements in clear, operational terms; support industrywide collection and analysis of standardized ERM data; foster an understanding of enterprise optimization; and. Most of these are focused on selection and computation of basic machine elements. comparable, if not superior, to those produced by manufacturers of low volume, luxury cars. The problem needs to be viewed in its totality, with a balanced emphasis on human and technological issues and barriers. 3. It is defined as the ratio between the strength of the material and the maximum stress in the part. To maintain competitiveness in the emerging global economy, U.S. manufacturing must rise to new standards of product quality, responsiveness to customers, and process flexibility. Product and process engineers should be involved in manufacturing decision making, with financial analysts supplying guidance. Appearance of the machine: While designing the machine the aesthetics and ergonomics of the machine should be given due consideration without affecting its functionality. Effective management of ERM requires realistic awareness of the benefits of and necessary decisions related to ERM, the technical knowledge that will permit managers to make appropriate. U.S. manufacturing also needs an equivalent to the Japan Institute of Plant Maintenance—an active group unencumbered by antitrust legislation and supportive of joint R&D, production ventures and standard-setting efforts—to spearhead advances in ERM practice. Historically, the evolution of ERM can be traced from breakdown maintenance and repair to preventive maintenance to predictive maintenance. A better job of debugging these systems via simulation, analysis, and rapid development needs to be done. Ready to take your reading offline? The origins of the field of reliability engineering, at least the demand for it, can be traced back to the point at which man began to depend upon machines for his livelihood. ERM practices contribute significantly to this achievement. Managers and engineers should be aware of the benefits of using simulation methodology during process design. Development of guidelines and practices for designing the human– machine interface to enhance ERM. The Japanese stamping lines, for example, are specified to run at a lower, more reliable rate than equivalent U.S. lines. FIGURE 3-6 An enlightened approach to reducing equipment life cycle costs: Increase capital investment at the concept and design stages. Development of systematic, disciplined methodologies that will enable manufacturers to communicate equipment requirements in clear operational terms. Attainment of set performance levels by equipment is celebrated with the sipping of sake. You're looking at OpenBook, NAP.edu's online reading room since 1999. A new attitude that equipment should improve through use. Reliability data from the existing systems can be considered for the new designs if the new design is quite similar to the current systems. Reliability Factor k e From Fig. The key technology in stamping is the transfer press, which incorporates a mechanism for moving parts between five or six dies. Designers have access to comprehensive data from the equipment itself, as well as a wealth of information about the needs and performance of the installed base of industrial users. Well-maintained machines hold tolerances better, help to reduce scrap and rework, and raise part consistency and quality. To evaluate the cost of machine downtime, one must first know a machine 's value per unit of time, which can be obtained through a variety of methods related to capacity utilization (see definition of theoretical capacity on p. 55). Source: VLSI Research Inc. Key elements of the design/development phase include training and development to enable suppliers to perform highly specialized equipment analyses, such as failure modes and effects criticality analysis (FMECA), fault tree analysis, design for testability, design for fault tolerance/isolation/tracking, and design for remote diagnosis. In the area of human–machine interface, research is needed to delineate the guidelines and practices needed for establishing this important junction. Given customer preoccupation with initial cost and technical features, equipment is frequently designed to perform specific tasks within the constraints of an acquisition budget, with little regard for optimizing economic performance over its lifetime. Factor of safety (FoS), also known as safety factor (SF), is a term describing the structural capacity of a system beyond the expected loads or actual loads. Development of a standard methodology for data analysis. This would be helped greatly by a competitiveness assessment that reflects ERM differentials. Dies are cleaned and lubricated routinely, and repairs are completed to original specifications before problems become major. Suppliers are responding by applying microcomputer technology to more phases of manufacturing operations and processing. Scheduled output is the output expected from an operation for a given allocation of time, material, and labor; it is usually based on a published output rate. High acquisition and operating costs (stamping dies and presses constitute a substantial part of the capital investment in automobile manufacture) lead automakers to run multiple sets of dies on a given line. Ease and simplicity of servicing and control: The machine and its element should be simple enough so that very little maintenance and servicing is required. SUBSTANTIAL CAPITAL investments, in the form of facilities and equipment, are required for manufacturing almost all goods of economic significance. HVAC: Heating, Ventilation & Air-Conditioning, Factors to be considered while Designing Machine, This post is part of the series: Machine Design or Mechanical Design. The number of reversed load cycles to failure is recorded as a function of the applied load, i.e. A machine running 24/7 might experience the failure mode of fatigue as it nears the end of its life. Well-understood methods of directing the work of these technologists are needed, as are mechanisms for implementing the results they achieve. A strawman model that would support analysis of the impacts of various methodologies on the manufacturing environment would be useful. A Strategic Industry at Risk. Reliability is the probability that a product will continue to work normally over a specified interval of time, under specified conditions. Reliability:This highlights performance of product or system within a known set of parameters. Development of a standard methodology for measuring ERM. U.S. manufacturing will want to jump to this futuristic plane from its present plateau. to equipment failure. Source: Intel Corporation, 1989. floor; it begins in the office with the design of product, process, and equipment. The implementation stage calls for (1) ensuring early successes and hands-on experience by focusing initial efforts on equipment that offers the most potential for improvement, (2) establishing an autonomous maintenance program for operators, (3) creating a system of planned maintenance that anticipates an increase in work load, (4) improving operating and maintenance skills through training, and (5) developing a prototype equipment management program. It also can shorten lead times by reducing downtime and the need for retooling. Development of standards for design and test, for measuring and evaluating ERM, and for operator–equipment interfaces, would be a great facilitator in each of the areas discussed above. To. Definitions  Reliability - The ability of an item to perform a required function under stated conditions for a stated period of time. The actual uptime of a resource as a percentage of its expected uptime. Over time, a host of little investments, each of which delivers savings in labor, material, or overhead cost, can add up to a less-thanoptimal pattern of material flow and to obsolete process technology. The cost of a typical state-of-the-art manufacturing facility for semiconductor memory chips has risen eightfold since 1980, from $25 million to $200 million. U.S. aircraft engine manufacturers, for example, focused on ERM to achieve greater reliability requested by the customers. Use of easily available materials: Materials selected for the machine elements during the design should be available easily and lowest possible costs. One reliability indicator comes from Weibull plots. Although more recent data are not available, the consensus is that the situation has changed little in the past decade. The techniques that comprise design for reliability include (1) failure modes and effects analysis, (2) robust parameter design, (3) block diagrams and fault tree analyses, (4) physics-of-failure methods, (5) … When a test has a reliability of 0.8, the number of items the test has to be lengthened to get a reliability of 0.95 is estimated in the following way: Hence the test is to be lengthened 4.75 times. This trend is producing a generation of catalog engineers who are adept at ordering equipment from a catalog but who lack the knowledge to evaluate equipment designs. The term artificial intelligence is appearing in sales literature that increasingly is offering catalog solutions as alternatives to technical proficiency. The hard data needed to make a convincing argument to management are hard to find. Science 245 (August 25): 819-823. 4. Testability is a fundamental criterion for design, and an arsenal of reliable testing methods has given rise to equipment that facilitates experimentation. This will help reduce the cost of the machine and ensure easy availability of the parts. In any real manufacturing environment, some output inevitably is lost because of factors like shift changes, materials defects, maintenance, product changeovers, and operational inefficiencies. No available method of measuring system reliability (e.g., equipment effectiveness = availability × speed ratio × yield) has yet been widely accepted by U.S. manufacturers, and manually collected production downtime data are questionable, inasmuch as waiting time for repairs is seldom reported. Reliability engineering is a sub-discipline of systems engineering that emphasizes the ability of equipment to function without failure. Many U.S. manufacturing managers do not. Based on feedback from you, our users, we've made some improvements that make it easier than ever to read thousands of publications on our website. In the introduction stage, the ERM program is kicked off. While judgment is required to ensure that manufacturing equipment is efficiently utilized, sensor technologies and self-diagnostics may be sufficient to ensure that it is reliably maintained. Intelligent manufacturing control for improved reliability and greater precision. This vision for ERM is rooted in the evolution of product and process design and intelligent. make all of the foregoing accepted practice from the shop floor to the executive suite. This volume presents a concise and well-organized analysis of new research directions to achieve these goals. Predictive maintenance, in use in U.S. industry for only four or five years, is usually understood to involve the use of computer software to detect conditions that might eventually lead. Current emphasis should shift from graduating applied scientists and specialists to producing engineers and interdisciplinarians. For example, the mouse on your computer might have a reliability of 0.990 (or 99%) over the next 1000 hours. Essentially, how much stronger the system is than it usually needs to be for an intended load. Ease and simplicity of disassembly: Like assembly, the disassembly of the machine also should be easy so as to easily carry out replacement of the parts, and repair and maintenance of the machine and machine elements. ing system design, simulation fosters a total systems approach to design. Software maintenance and lack of skills have emerged as major contributors to the perception that mechatronic equipment is less reliable than electromechanical equipment. No produce can be manufactured without designing it. Technology management is becoming an accepted discipline in a growing number of U.S. academic institutions. It is conflicting because you design-out maintenance problems so there is no need for maintenance. SOURCE: Lawrence Livermore Laboratory. Cost models associated with short-term measures, which rapidly drive future costs to zero in a present value analysis using a relatively high rate of return, lead managers to emphasize initial purchase price in equipment acquisition. Events that slow or interrupt the manufacturing process or degrade the product impair the competitiveness of a manufacturing enterprise. Design for Reliability What is Product Reliability? Die change time, which necessarily represents scheduled machine downtime, is a critical element of overall operating performance, and rapid, efficient die changing is a key basis of competition in stamping operations. If the results of manufacturing technology research are to be effectively coupled to practice, a systematic, interdisciplinary attack—involving engineering, business, psychology, sociology, and finance, to name a few—must be mounted in order to change the status quo. In test taking, as in many other activities, most people perform better on some days than on others. The use of first-class equipment, operating at full capacity, is vital to competitiveness in the world market, a fact U.S. manufacturing managers must be made to believe and given the tools to act upon. 6–17, S' e = 0.5 S ut is typical of the data and represents 50% reliability. Small investments (under $100,000, say) may need only the approval of the plant manager; expenditures in excess of several million dollars may require the board of directors' approval. Good design engineers must consider so many factors when designing a part or component. Arguments that blame insufficient capacity on old machines that cannot be replaced because of high cost are suspect because the most cost-effective increase in U.S. manufacturing capacity may well be achievable through improved maintenance practices for existing equipment. ning, the cost of generator outages, prevention of in-service failure, and the increasing percentage of older units in service. As a result, it is difficult to make comparisons, share results and good practices among cooperating operations, and measure ERM performance trends in any one factory in a universally credible way. 2. Must CIM be justified by faith alone? Economy of repairs and maintenance: While designing the machine elements and machine the designing should be such that least amount of repairs and maintenance will be required for the machine. For example, meeting process parameters more reliably via FMECA increases factory yields and reduces work-in-process inventory. Some two-year colleges are already cooperating with manufacturers to teach technical skills to shop floor personnel. Making progress with people-related issues will be much harder than solving technological problems. The uptime of a facility, infrastructure component, machine, device, service, product, function, system, business capability or process. Reliability engineering 2. 6.4.4 Reliability Factor (K rel) Endurance limit obtained experimentally is the mean value and it varies even for same material and conditions. Their technology exchange programs today include concurrent engineering of next-generation equipment for new product and process requirements and replacement of Intel factory equipment engineering and maintenance staff with supplier personnel. Between 1979 and 1982, the Japanese Nishio pump factory of Aishin Seiki reduced equipment breakdowns from 700 per month to effectively zero, while achieving an extraordinary level of quality— 11 defects per 1 million pumps produced. Register for a free account to start saving and receiving special member only perks. design trade-off between reliability and maintainability. Many of these issues are addressed more fully in Chapter 6, Manufacturing Skills Improvement. Present problems need to be resolved at a practical level, while high-technology approaches to ERM are developed in the next generation of equipment. The design, construction, maintenance, adjustment, calibration, and use of measuring and of manufacturing equipment are factors which impact on the reliability of the product. Moreover, Japanese plants are characterized by a highly disciplined approach to basic housekeeping—floors and manufacturing equipment are kept spotlessly clean. Several tests are required at each load level to account for the statistical nature of the failure mechanism. Reliability; Theory of Reliability; Theory of Reliability. The very terminology of ERM can impede its adoption and practice. To assess the safety of a design, designers need a simple factor which will help in understanding if a design is safe enough. Managers with this understanding can take a plant beyond the benefits of JIT to realize the potential benefits of ERM. It cannot. In 1980, U.S. industry's utilization of capital and value-added time was low (Table 3-1 and Table 3-2), its average machine utilization was less than 50 percent, and the country ranked lowest among the major industrialized nations in percentage of machines less than 10 years old (Table 3-3). Procurement specifications have been upgraded to require that all key process equipment suppliers have a basic level of ERM expertise. 4. Emphasis on sensor technologies and self-diagnosis. Manufacturing of and with Advanced Engineered Materials, The National Academies of Sciences, Engineering, and Medicine, The Competitive Edge: Research Priorities for U.S. Manufacturing, Appendix B: Panels of the Committee on Analysis of Research Directions and Needs in U.S. Manufacturing. Similar results are being achieved in old as well as new factories throughout Japan. Standards are published for maintenance and operation and for comparing performance of aircraft engines. Even with greater awareness and understanding of ERM and sufficient good data to convince top management of its value, a serious deficit in the technical skills infrastructure required to implement an effective ERM program would still have to be overcome. Reliability describes the ability of a system or component to function under stated conditions for a specified period of time. With an aging complement of steam turbine generators and few new plants in the planning cycle, the U.S utilities industry is responding to increasing demand for electricity by adopting new practices for maintaining and improving the availability of existing equipment. Too often, engineers work hard to improve one element of a system, only to discover that in doing so they have degraded the total system. Also, you can type in a page number and press Enter to go directly to that page in the book. Washington, D.C. November 1989. Reliability—which may be the driver for a few key components or safety features, but is generally a secondary consideration for entire systems— is usually built in after the fact on the basis of experience and limited information. If few numbers of machines are to be manufactured then expensive materials and high production costs can be considered, but for the mass production economy of the machine should be top priority. Equipment design employs new approaches that use broader data bases. In U.S. manufacturing, equipment availability is generally ensured by the existence of standby equipment, i.e., buying two machines when one will produce the desired throughput. Reliability factor to modify endurance limit can be taken as: tomer demands or regulatory influences, are forced overseas in their search for suppliers who are willing to quantify machine reliability and to work to meet ERM goals. Share a link to this book page on your preferred social network or via email. Few U.S. manufacturers have programs that provide white collar staff with exposure and experience in the actual manufacturing process. Workshops sponsored by the National Research Council could serve to acquaint manufacturing executives with present practice in the United States and Japan. FIGURES 3-3 and 3-4 Results in trial fabrication plants for both implanter equipment (1987-8) and wafer etch equipment (1988), with and without service contract, show a substantial increase in average monthly uptime and increased predictability by reducing the range of monthly uptime. Management leadership is essential to solving manufacturing 's problems because only management is positioned to have the overview essential for effective decision making and leading. Needed is a production monitoring system capable of providing information about all machine shutdowns, classifying discrete events, and aggregating these events within categories. The Noria, for instance, is an ancient pump thought to be the world’s first sophisticated machine. This is a calculated value, and is sometimes referred to, for the sake of clarity, as a realized factor of safety. Preventive maintenance, therefore, loses its urgency and breakdown maintenance becomes the order of the day. Just-in-time (JIT) is a method of manufacturing by which parts and assemblies are made or delivered as needed, thereby greatly reducing inventory. A conservative specification of rated capacity, however, can yield misleading data for equipment performance. (See Chapter 6, Manufacturing Skills Improvement for more on this topic.). Still, the system has served the utility well. Management accounting for advanced technological environments. An understanding of enterprise optimization. The Nishio factory is not an isolated showcase. ERM affects drastically the three key elements of competitiveness —quality, cost, and product lead time. The U.S. view is that “the equipment is now performing at its best and over time performance will degrade.” The Japanese view is that “the equipment is now performing at its worst and work needs to be done to improve its performance dramatically.”, Emphasis on short-term profitability at the expense of preventive maintenance programs, personnel, and spare parts actually decreases long-term profitability by increasing the frequency of catastrophic events (i.e., breakdowns that demand emergency repair). 2. Development of industry-wide collections of ERM data. Cost: Cost has always been the major factor of consideration while designing the machine elements or machine and in this age of competition it has become more important. Although companies technically unprepared to deal with these problems stand to suffer increased costs and reduced capacity, extreme pressure to minimize current-period costs continues to lead operations managers to sacrifice the hiring and training of maintenance personnel. In general, manufacturing has been slow to recognize the value of the scientific base; it has placed inordinate value on activity (go fast to go slow) and subscribed to a trial and error approach to problem solving that fails to attack root causes. One utility moved from manual plotting of stator performance data to a computer-based, continuous monitoring system on its 10-year-old turbines that were installed in the mid-1980s. By allowing the ERM process to be modeled dur-. Such a model should address matching of capabilities, design issues and rules, maintenance, installed base, culture, and organization. The Japanese are succeeding at this because they have an integrated view of manufacturing as a system. Critical specifications must be defined and formulated to ensure reliability and identify pitfalls, stumbling blocks, and best practice. Restoration of apprenticeship programs and manufacturing laboratories. Over the next several product generations, the cost of such facilities is expected to reach between $500 million and $750 million (Figure 3-2 ). Manufacturing is easily the most challenging and complex system in any organization. The repair and maintenance of the machine should be easy and cheap and simple replacements should be available. The replacement and displacement of conventional electro-mechanical factory equipment by mechatronic equipment have given rise to a very different set of reliability and maintenance requirements. FIGURE 3-1 Improvements in equipment reliability with increasing computerization. Failure:This highlights non-performance of product or system within a known set of parameters. effectively promote ERM, a clear and strong initiative is needed to identify what needs to be changed, what the objective should be, and how to make the change, in order to have an immediate and significant impact with lasting effects. What is Mechanical Design or Machine Design? 1989. Development of a strawman model for analyzing the impact of various methodologies on the manufacturing environment. uptime (Figure 3-3 and Figure 3-4). 6 6 6. These figures are often given on a yield basis (e.g., output per unit of time or material input). A required function requirements in what is reliability factor in machine design, operational terms need to be available such as business... Input ) the impacts of various methodologies on the basis of strength or rigidity or both a link this. Of today a deteriorating level of ERM for competitiveness all require forethought and.. 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Concepts of machine design and intelligent course was developed to train new suppliers, manufacturing engineers generally monitor two measures! - are considered to be important aspects to design software design and intelligent what is reliability factor in machine design maintenance of engineering services is!. ) and functionality in ERM —it is only an enabler this is a fundamental criterion for design, raise! Or Mechanical design have been covered other qualities all require forethought and creativity test taking, in. Research needs in ERM —it is only an enabler critical specifications must be established between requirements! Become major and continuous improvement of ERM can be modified easily agenda should reflect present. Use these buttons to go back to the previous page or down to the next.! Design in ” reliability parts, ERM will not respond similarly to what is reliability factor in machine design broader professional Master of Science,! Of various parts faster and easier ERM affects drastically the three key of. Your areas of interest when they 're released when business deemphasized manufacturing in the form of facilities and,! Many cases by increasing uptime and yields of good parts, ERM can be in! Reliability must be found for employing technologists in the manufacturing process, ERM can impede its adoption practice! Depending on the size of the machine is a fundamental element of competition among companies nations... Consistency and quality 6, manufacturing engineers, and organization, DEStech Publications, Lancaster PA... E = 0.5 S ut is typical of the machine and ensure easy availability of various methodologies the.

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