SMED/Quick changeover (Single-Minute Exchange of Die) is a concept for organizing the process of changeover/retooling of equipment, which can significantly reduce the time spent on equipment changeover.

The concept originated in Japan in 1950 at machine-building factories, the author of the concept is Shigeo Shingo, who developed this concept for 20 years (1950 -1970). Assuming that any changeover could be accomplished within 10 minutes, he called his concept SMED.

Further improvement of SMED led to the emergence of the OTED (One-Touch Exchange of Die) concept - the concept of replacing dies in no longer than one minute.

The SMED/OTED methods are based on what was discovered in the 50s of the 20th century. Shigeo Shingo divides the changeover process into two types of operations:

Internal Exchange of Die (IED) are operations that can only be performed while the machine is stopped, such as mounting or removing a die.

External Exchange of Die (OED) are operations that can be performed while the machine is still running, such as transporting a die to and from a storage location.

There are 8 main methods of the SMED system used to reduce changeover time:

1. Separation of internal and external changeover operations

It is necessary to clearly define which changeover operations must be performed while the machine is stopped and which can be performed while the machine is running.

2. Transformation of internal actions into external ones

The transformation requires a review of operations in order to check whether among the actions classified as internal changeover, there are no ones left that are actually or may be external.

3. Standardize function, not form

Standardization of die shape is costly, while standardization of function only requires uniformity of parts required for the changeover operation. For example, adding a plate or block to the edge of a die fixture standardizes the dimensions of just that part and makes it possible to use the same fixtures across different setups.

4. Use of functional clamps or complete removal of fasteners

In practice, the most commonly used fastening device is a bolt, but its use is sometimes very time consuming. For example, a bolt with 15 threads needs to be turned 14 times before it is actually tightened on the last turn. But only the last turn is needed when tightening and the first when loosening, the remaining 13 are wasted movements. Bolts are not the only fastening method; one-touch fastening methods that use wedges, pins, and latches or springs as gripping devices to simply connect two parts reduce installation time to seconds.

5. Use of additional devices

Some of the delays associated with internal adjustments can be eliminated by using standard fixtures. When a workpiece secured in one fixture is processed, the next workpiece is installed in the second fixture. When processing of the first workpiece is completed, the second fixture is easily placed on the machine for processing.

6. Application of parallel operations

If a changeover operation requires setting operations on all sides of the machine, and if these operations are performed by one worker, then a lot of time and effort is spent walking around the machine. But when parallel operations are performed by two people, changeover times are usually reduced by more than half due to the savings in movement. For example, an operation that takes one worker 30 minutes will take only 10 minutes for two.

7. Elimination of adjustments

Typically, adjustments and test runs take up 50-70% of the internal setup time. Eliminating them provides amazing time savings. Eliminating adjustments begins with the understanding that setting switches/controls and adjusting are two separate and distinct functions. Adjustments can be eliminated by using a device to accurately determine the correct position of the limit switch/regulator. Then the only necessary operation is to set the switch/regulator. Of course, the best adjustment is no adjustment. For example, adjustment can be eliminated completely when the number of control positions is limited and constant.

8. Mechanization

Mechanization should be considered when all efforts have been made to improve the changeover process in all the ways described above. Mechanization is essential for replacing large fixtures and dies, casting and compression molds. Fastening of any parts can be done using air or oil pressure. However, investments in mechanization should be assessed very carefully. If the changeover time is reduced by previous methods from 2 hours to 3 minutes, mechanization will most likely reduce this time by no more than another minute.

Implementation stages

SMED takes a progressive approach to changeover improvement. In this case, you need to go through 4 stages:

At this initial stage no distinction is made between internal and external actions. Many external activities, such as searching for tools and preparing the die, are performed while the machine is stopped. This causes unnecessary lengthening of changeovers.

This is the most critical stage in SMED implementation. It provides for the separation of internal and external adjustment operations. Make a check sheet, including all the components, operating conditions and steps that need to be performed while the machine is running. Then check the functioning of all components to avoid delays during internal adjustments. Finally, the most efficient way to transport dies and other parts during machine operation must be researched and implemented.

Analyze the current changeover process to determine whether any of the internal activities can be converted to external ones. For example, warming up the mold while the machine is still running eliminates the need to warm up the mold while the machine is stopped.

Review internal and external setup operations to identify additional opportunities for improvement. Consider eliminating adjustments and changing fastening methods.

Over the years, of the several hundred improvements to SMED, the most effective have been:

clear separation of internal and external changeovers

if possible, complete conversion of internal adjustment into external

elimination of adjustments

fastening without screws

The speed of changeover is one of the key indicators characterizing the efficiency of an enterprise. Shigeo Shingo has developed a revolutionary changeover time reduction technology that can be applied to any process. The practice of not only foreign, but also many Russian companies proves that changeover time can be reduced from several hours to several minutes. We recommend using this book when training operators and foremen of manufacturing companies, as well as when teaching students of technical and economic specialties.

Book output:

Adapted from Shiego Shingo, A Revolution in Manufacturing: The SMED System, English edition 1985 by Productivity Press (based on Shinguru dandori, 1983 by the Japan Management Association; originally translated by Andrew P. Dillion.

Quick changeover for workers / Per. from English - M.: Institute of Complex Strategic Studies, 2009. -112 p.

ISBN (English) 978-1-5632Л-25-0, ISBN (Russian) 978-5-903148-28-8, UDC 65.0 (07), BBK 65.290-2я7

Translation from English Alexandra Ryzhkova, executive editor Alexander Nizhelsky, scientific editing Vyacheslav Boltrukevich, literary editor Larisa Pavlova, proofreading by Galina Kulik and Olga Pavlovskaya, technical editor Andrey Sobolev, layout by Andrey Sobolev, cover design by Andrey Sobolev.

Signed for publication on September 29, 2008. Format 60x90/16. Offset paper No. 1. Offset printing. Volume 7 p.l. Circulation 2000 copies. Order No. 2644. Printed by OJSC IPK Zvezda.

Chapter 2: Important Terms and Concepts

Chapter 3. Preparing for SMED Implementation

• Basic setup steps
  • Preparation, adjustment, checking of materials and tools
  • Installation and dismantling of cutters, tools and parts
  • Measurements, setup and calibration
  • Test runs and adjustments
• Analyze setup operations in your production
• Three stages of the SMED system
  • Step 1: Separate internal and external changeover activities
  • Step 2: Convert internal changeover activities into external ones
  • Step 3: Streamline all changeover activities
• In conclusion
  • Conclusions
  • Time to think

Chapter 4: Step 1: Separate Internal and External Changeover Activities

• Description of stage 1
• Checklists
• Functional tests
• Optimizing the transport of parts and tools
• SMED in action: Mold transport as an external changeover operation
• In conclusion
  • Conclusions
  • Time to think

Chapter 5: Step 2: Convert Internal Changeover Activities to External Changeover Activities

• Description of stage 2
• Preliminary preparation of working conditions
• Standardization of functions
  • We introduce standardization of functions
  • SMED in Action: Standardize the Mold Holding Function
  • SMED in Action: Use a Mold Alignment Template
  • SMED in action: use the cassette mold system
• Auxiliary equipment
  • SMED in action: Use tooling to handle multiple molds at once
  • SMED in action: use milling machine accessories
• In conclusion
  • Conclusions
  • Time to think

Chapter 6: Step 3: Streamline All Changeover Activities

• Description of stage 3
  • Optimize external changeover activities
  • SMED in Action: Optimize Storage and Transportation Operations
  • Optimize internal changeover activities
• Implement parallel operations
• Use function clamps
  • Single turn fasteners
  • One-touch fasteners
  • Locking latches
• Eliminate equipment adjustments
  • Fixed numeric settings
  • Visible center lines and additional planned ones
  • LCM system
• Mechanization
• In conclusion
  • Conclusions
  • Time to think

Chapter 7. Conclusions and comments

Preface

The new book in the Lostless Manufacturing series will introduce you to a unique system that will make your production process more productive and your work easier and more enjoyable. From this book you will learn how you can change equipment in record time - less than ten minutes. The system in question is known by the English abbreviation SMED (Single Minute Exchange of Dies) or the name “fast changeover”.

One of the first experiences of introducing the SMED system into the production process of Toyota proved that the changeover of a large 1000-ton press can be completed not in four hours, as was previously done, but in just three minutes. The speed of equipment changeover plays an important role for any company seeking to build its production process on the principles of “just in time” and production in small batches. Fast changeover for such companies provides the opportunity to quickly change the model range and avoid the accumulation of excess product stocks in the warehouse. The SMED system, which is the focus of this book, is the most effective approach to reduce equipment changeover time. Thanks to this system, you will be able to significantly reduce the number of complex, time-consuming and unproductive actions for reconfiguring equipment, or even get rid of them altogether, which will undoubtedly not only make your work easier personally, but will also make your company more competitive.

The SMED system is a simple and versatile solution that is successfully used in various companies around the world. Although the system was originally designed to streamline die changeover work (hence its name), the basic principles of “fast changeover” were quite applicable to a serious problem: how to reduce changeover and preventative maintenance time in manufacturing, assembly shops and even in the service sector. The system is now used everywhere from machine shops and packaging lines to airlines.

The SMED system demonstrates a truly new way of looking at the changeover process. Its creator, Shigeo Shingo, visiting production facilities and observing what and how workers do during equipment changeover, realized that all the actions necessary during changeover can and should be done in the shortest possible way. When Shigeo Shingo taught people the basics of SMED, he did so through case studies and stories of how changeover processes were optimized in various plants. He convincingly argued that it was necessary to move away from the “template” approach to changeover, look at this process from a different point of view and find a better and more effective solution. We hope that in this book we have managed to preserve the unique style of Shigeo Shingo.

Rapid Changeover for Workers is based on Dr. Shigeo Shingo's seminal and comprehensive work, Rapid Changeover: A Revolutionary Technology for Manufacturing Optimization, aimed at managers. But it will be those on the front lines of manufacturing and assembly that will be directly involved in implementing SMED, and they will be the ones who will benefit most from the system. This book is written specifically for workers to become familiar with the basic principles of "fast changeover." Once you have mastered the essence of the SMED system, you will be able to apply it in your everyday work.

The book explains why implementing SMED is important for companies and workers. The three basic stages of implementing “fast changeover” are outlined in detail. You will get the most benefit from this book when studying in a group, which is why the material in the chapters is presented in short blocks, each of which can be mastered in one lesson (Chapters 5 and 6 contain many examples, so we recommend devoting two lessons to each of them) . At the end of each chapter you will find questions to discuss with other group members.

We hope that this book will give you, although not exhaustive, quite complete information about what the SMED system is, how to implement it in your company's activities, and how this system will make your work easier and more efficient.

Getting started

Purpose of this book

Quick Changeover for Workers is written to provide the information you need on how to implement a SMED system in your workplace. The goal of “quick changeover”, or SMED (from English Single Minute Exchange of Dies, quick replacement of dies) is to significantly reduce equipment changeover time.

What is the basis of this book?

The predecessor of this book and its basis is the work of Shigeo Shingo “Fast Changeover: A Revolutionary Technology for Production Optimization,” published in Russian by Alpina Business Books in 2006 (see Figure 1-1).

It took Shigeo Shingo nineteen years to develop the SMED system. While studying equipment changeover operations in many factories, he discovered two important things that formed the basis of SMED:

1. Changeover operations can be divided into two categories:

Internal changeover actions, that is, operations that are performed after the equipment is stopped.

External changeover actions, that is, operations that can be performed while the equipment is running.

2. Converting as many internal changeover operations as possible into external ones allows you to reduce the equipment changeover time by several times.

In your hands now is a book that presents the basic concepts and tools described in the work of Shigeo Shingo. Since working with this fundamental work would require considerable effort and time from you, our book contains an abbreviated and simplified version of it.

However, in order to clarify certain points or obtain more complete information, including the features of the practical implementation of the SMED system in various work situations, it is advisable to use the original source.

Chapter overview

Chapter 1: Getting Started

This is the introductory chapter you are reading now. It explains the purpose of the book "Fast Changeovers for Workers" and how it was written. This chapter provides tips on how to get the most out of what you read. It also provides a brief introduction to each chapter.

Chapter 2: Important Terms and Concepts

This chapter provides an overview and definition of the SMED system. It also discusses why the SMED system is important to companies and how these companies benefit from implementing the system. The following is a list of the most important terms and concepts with definitions to help you master the rest of the book.

Chapter 3. Preparing to implement the SMED system

The four basic steps of the traditional changeover procedure are commented on here. It then looks at the first steps of implementing a SMED system, describing how to analyze your current changeover operations. Finally, an overview of the three phases of rapid changeover implementation is provided.

Chapter 4: Step 1: Separate Internal and External Changeover Activities

Chapter 4 covers the first stage of "fast changeover". Three practical methods used to separate changeover operations are explored through examples: checklists, functional checks, and optimizing the transport of molds and other parts.

Chapter 5: Step 2: Convert Internal Changeover Activities to External Changeover Activities

This chapter discusses the second stage of the SMED system. Descriptions and examples of three methods used are provided: pre-conditioning, standardization of functions and auxiliary equipment.

Chapter 6: Step 3: Streamline All Changeover Activities

A description of the third stage of “fast changeover” is given. Five methods for increasing the efficiency of internal and external changeover operations are studied, including examples: optimizing the storage and transportation of materials and tools, introducing parallel operations, using function clamps, and eliminating adjustment operations.

Chapter 7. Conclusions and comments

This chapter provides final observations and reflections. The possibilities of practical application of the material you have studied are discussed; Recommendations are provided for creating your action plan for implementing a SMED system. The chapter also introduces opportunities for further study of the SMED system.

Introduction: What is the SMED system?

SMED is an abbreviation of the English term Single Minute Exchange of Dies. In essence, the SMED system is a set of theoretical and practical methods that can reduce the time of equipment setup and changeover operations to ten minutes. The system was originally developed to streamline die changeovers and related equipment changeovers, but the principles of “fast changeover” can be applied to all types of processes.

It should be emphasized that in almost all cases, the use of the SMED system can significantly reduce changeover time, but it cannot guarantee that the time of all setup processes will be reduced to ten minutes or less. In turn, reducing equipment changeover time provides your company and you personally with many benefits.

In subsequent chapters, you will become more familiar with “fast changeover” and understand how the SMED approach differs from traditional changeover operations. You'll also learn why this system is so important and how you can use it to make your work more efficient and enjoyable.

Rice. 2-1. Problems of high-volume production

Productivity Press Development Team

Productivity Press has been publishing books on the world's best practices in manufacturing improvement since 1981. The “heart” of the publishing house is a group of developers - editors, writers and experienced experts in various fields of activity who work tirelessly to bring the most relevant and necessary information to their readers. They read new books, learn new terms, and keep up with new trends in manufacturing and publishing. They constantly study themselves and do everything to ensure that the books and other educational materials published by their publishing house are useful and meet the needs of readers.

Shigeo Shingo was born on January 8, 1909 in the Japanese city of Saga. His career took more than 50 years, which he devoted to the problem of improving and rationalizing production methodology. Along with Taiichi Ohno, he is considered one of the founders of the Toyota Production System.

Between 1976 and his death in 1990, Shigeo Shingo actively consulted and lectured to senior management and factory workers in Europe and the United States. He wrote more than 20 books. In 1988, he established the annual University of Utah Award. Shingo for Process Improvement, which is awarded to North American businessmen, students and teachers.

Emergence of SMED

In the spring of 1950, I conducted research at the Mazda Toyota Toyota plant in Hiroshima to improve production efficiency. At that time, three-wheeled cars were produced there. Toyo wanted to alleviate bottlenecks caused by the 350, 750 and 800 ton large body presses that were operating at partial load. I toured the facility and asked the department head in charge of production to allow me to time it for a week to determine how the presses worked. He replied that this would be a waste of time: he already knew that it was the presses that were to blame for the formation of bottlenecks, and he assigned the most qualified and conscientious workers to work on them. With three presses running around the clock, he believed the only way to increase production was to purchase more equipment. He really hoped that senior management would do just that.

“Well, that’s bad,” I said. - But maybe I can still conduct such an analysis? If it turns out that there is no other way to eliminate bottlenecks, then I will recommend that management purchase additional equipment.” After that, I was allowed to conduct such a study.

On the third day, dies were changed on an 800-ton press. The workers removed the old die and began running around the press. I asked the operator what was going on. He said: “One of the mounting bolts for the new die is missing. I was sure that it was in the stamp, but I can’t find it, although I’ve already looked everywhere.”

- When you find him, will you go to the press? “I’ll be here waiting for you,” I said.

“Okay,” he said. “But I still get nervous when you’re here.”

I sat down near the press and waited. More than an hour later, the operator came running, covered in sweat, holding the bolt in his hand, shouting joyfully: “Here it is!” I found it! In fact I didn't find it. I simply took a long bolt from a nearby press, trimmed it and tapped it. That's why I was delayed. You can believe it was not easy!” - he said.

I sympathized with him, but then another thought began to bother me: You cut a bolt taken from another press. And when you need to change the tool on that press, what will you do? Does this happen to you all the time?

- No, not all the time. From time to time there are such incidents,” he replied.

That's when it occurred to me that there are two fundamentally different types of changeovers: internal adjustment— operations of installing and removing dies, which can only be performed with the press turned off; external adjustment— actions for transporting old dies to the warehouse, delivering new dies to the press; These operations can be performed without turning off the press.

Bolt preparation is an external operation. It made no sense to stop running an 800 ton press because a bolt was missing. It was only necessary to clearly work out the external changeover procedures, including checking the presence of bolts for the upcoming changeover.

We have developed a careful procedure for selecting and storing all bolts in appropriate boxes. We have also improved the changeover process by performing all possible operations as external ones. This increased efficiency by about 50% and the bottleneck was resolved. After that, I made it a rule to clearly distinguish between internal and external operations.

This is how the newborn SMED concept took its first steps at Toyo Kogyo.

Second episode

In the summer of 1957, I was asked to conduct research at the Mitsubishi Heavy Industries shipyard in Hiroshima. When I asked the director of the repair plant, Mr. Matsuzou Okazaki, what the problem was, he said that the large planer for machining diesel engine parts was not being used at its designed capacity and it was desirable to simplify the operation.

After analyzing the production process, I discovered that the markings for alignment and the dimensions of the engine cylinder block were made directly on the machine table. This greatly reduced the speed of work. As I was discussing this with Mr. Okazaki, it dawned on me: Why not install a second table for the planer and perform the marking operation on it separately? This way we could simply change tables as we move from one batch to the next, and this would significantly reduce the changeover time during machining. Mr. Okazaki agreed to this change.

The next time I arrived at the plant, I found that the installation of the additional table had been completed. The implementation of this solution made it possible to increase productivity by 40%. Both Mr. Okazaki and I were delighted with this result and congratulated each other on this achievement, although I now have one regret. If I had already been able to realize the importance of transferring internal operations to external ones, then the SMED system would have been developed twelve years earlier.

Episode three

In 1969, I visited the body parts shop at the main plant of the Toyota Motor Company. The site manager, Mr. Sugiura, told me that they can set up a 1,000-ton press in four hours, although Volkswagen in Germany can set up a similar press in two hours. Mr. Sugiura received clear instructions from management to meet even less time.

Together with the foreman and the director of the plant, we began to look for a solution to the problem. We began to clearly separate activities into internal and external, trying to optimize them separately. After six months, we managed to reduce the changeover time to one and a half hours.

We were all very pleased with this success, but when I returned to the workshop a month later, Mr. Sugiura had interesting news for me. Management ordered him to reduce the changeover time to three minutes! For a moment I was stunned. But then inspiration appeared: why not transform internal operations into external ones?

New ideas began to emerge quickly one after another. On the boardroom board, I outlined eight methods for reducing changeover time. Using this new concept, after three months of hard work we were able to achieve the desired time of three minutes. In the hope that any changeover can be accomplished in less than ten minutes, I called this concept SMED. The SMED system was later adopted by all Toyota facilities and continued to develop as a core element of the Toyota Production System. Now its use has spread throughout Japan and the world.

Mr. Taiichi Ohno, former vice president of Toyota Motor Company, wrote about SMED in June 1976 in the article “Implementing Wisdom in the Enterprise” ( Published in Management magazine, published by the Japan Management Association):

“Ten years ago, we tried to organize production in such a way that it would fit as much as possible into normal working hours. The change of cutters, drills and similar tools was usually carried out during the lunch break or in the evening. Our rule was to change cutters every 50 parts. However, as production volumes increased over the past ten years, machine operators began to complain that changeovers were taking too long. At the machining center, replacing numerous cutters and drills took half a day. If tool changes were made on a workday, production had to stop in the afternoon, forcing workers to go to work on Sunday.

It was irrational. Since we wanted to carry out scheduled repairs during working hours, we began to study the question of how to reduce changeover time as much as possible. Shigeo Shingo of the Japan Management Association was promoting a "die change system in less than ten minutes," and we thought such a concept would be very useful to us. It happened that after we spent half a day on readjustment, the machine worked for only ten minutes. It is logical to assume that if changeover takes half a day, then production should take at least no less. But then we would have a lot of excess products that we would not be able to sell. We are currently looking at ways to reduce changeover times to just a few seconds. Of course, this is easier said than done. But be that as it may, the time for readjustment must be reduced.”

This passage highlights the impact of reducing changeover times on improving overall manufacturing performance.

The development of the SMED concept took a total of 19 years. It arose from a deep understanding of the practical and theoretical aspects of changeover rationalization. An important role was played by the requirement of Toyota Motor Corporation to reduce the press changeover time from four hours to one and a half hours.

I would like to emphasize that the SMED system is based on both theory and many years of experimental practice. It represents a scientific approach to reducing changeover times that can be applied to any plant and any equipment.

MAIN STAGES OF THE CONVERSION PROCESS

Typically, changeover procedures are presented as infinitely varied, depending on the operation and type of equipment used. However, if we analyze these processes from a different point of view, we can see that all changeover operations consist of a certain sequence of steps. With the traditional changeover method, the time distribution usually corresponds to that presented in table. 3.1.

Table 3.1. Stages of the changeover process

Let's look at each of them in more detail.

Preparation, post-operative adjustments, checking workpieces, tools, etc. At this stage, all materials and tools are checked for availability in the right place and suitability for the job. This stage also includes the post-processing period, during which the products are removed from the equipment and transported to a storage location, time for cleaning the equipment, etc.

Installation and removal of cutters, tools, workpieces, etc. — operations of removing products and tools after completion of processing and installation of parts and tools for the next batch.

Measurements, parameter setting, calibration - all measurements and calibrations that must be made to perform a production operation - alignment, marking, measuring temperature or pressure, etc.

Trial runs and adjustments. Adjustments are made after processing the trial product. The higher the accuracy of measurements and calibration at the previous stage, the simpler the upcoming adjustment.

The frequency and duration of trial runs and adjustments are determined by the qualifications of the installation engineer. The biggest challenges in changeover operations are the correct adjustment of the equipment. The largest portion of test run time is due to such adjustment problems. If we want to make trial runs and adjustments easier, we must understand that the most effective approach is to increase the accuracy of the measurements and calibrations in the previous step.

Rationalization of changeover: main stages

The main stages of the changeover improvement process are presented in Fig. 3.2.

Rice. 3.2.

Preliminary stage: changeover conditions are not divided into internal and external

When carrying out changeover according to the traditional scheme, external and internal operations do not differ; what could performed as an external operation is performed as an internal operation, so the equipment is idle for a long period. When implementing SMED, the actual conditions in the workplace must be examined very carefully.

The best approach would probably be continuous production analysis performed with a stopwatch in hand. Such analysis, however, is time-consuming and requires high qualifications.

Another possibility is job sampling. The problem with this option is that sample works only accurately reflect the actual picture when they are repeated frequently. This method may not be suitable if few actions are repeated.

The third interesting option is to study the actual conditions in the workshop by interviewing workers.

The best method is video shooting the entire retooling process. It is extremely effective if the recording is shown to workers immediately after the changeover is completed. Allowing workers to speak often produces surprisingly clear, useful insights into issues. In many cases, this new understanding can be put into practice immediately.

Although many consultants advocate in-depth, continuous analysis of production to improve changeover processes, in fact, informal observation and discussion with workers is often sufficient.

Stage 1: separate internal and external changeover activities

The most important step in implementing SMED is to differentiate between internal and external changeover activities. I think everyone will agree that preparation of parts, maintenance, etc. does not have to be done with the equipment turned off. However, it is surprising how often this is done.

If you conduct special research on transferring as many operations as possible from internal to external, then the time of internal operations performed when the equipment is turned off can usually be reduced by 30-50%. Thus, a clear understanding of the differences between internal and external activities is the essence of SMED.

Stage 2: Convert Internal Actions to External Actions

I just noted that typically changeover times can be reduced by 30-50% by separating internal and external procedures. But even this huge reduction is not enough to achieve SMED's goals. At the second stage - converting internal readjustment into external - you need to:

review all transactions to determine if any activities are being misinterpreted as internal; find ways to convert these operations into external ones. This may include, for example, the heating operation, which was previously carried out only after the start of changeover, and the alignment operation, which can be performed before the start of production.

It is often possible to convert an internal changeover into an external changeover by taking a closer look at its function. It is extremely important to identify a new point of view, not bound by old habits.

Step 3: Simplify all aspects of the changeover operation

Although sometimes it is possible to do it in less than ten minutes by simply converting internal actions into external ones, in most cases this is not possible. That is why a focused effort must first be made to simplify all basic internal and external operations. Thus, stage 3 requires a detailed analysis of each elementary operation. The following examples indicate the successful implementation of stages 1, 2 and 3.

• At Toyota Motor Company, the internal changeover time of a bolt cutting machine, which was previously 8 hours, was reduced to 58 seconds.
• At Mitsubishi Heavy Industries, the internal changeover time of a 6-spindle drilling machine, which was previously 24 hours, was reduced to 160 seconds.

It is not necessary to perform steps 2 and 3 sequentially; they can be performed almost simultaneously. I have separated them to demonstrate two essential conditions: first analysis, then implementation.

CONCLUSION

The SMED system has been developed over 19 years based on careful analysis of the theoretical and practical aspects of changeover improvement. Thus, analysis and implementation serve as the basis of the SMED system and should be included in any improvement program.

There are two types of changeover actions - internal and external. The three main steps to improving the changeover process involve separating the two types of activities and converting internal changeover activities to external ones. Once this is done, all aspects of the changeover should be simplified as much as possible. Improvements to the changeover process can be made at any stage.

Chapter from the book "Fast Changeover. Revolutionary Technology for Production Optimization" by Shigeo Shingo, kindly provided by the publisher

Introduction

Modern companies are constantly developing, trying to improve their products and production. This provides a significant competitive advantage, increasing customer share and increasing profits. The main task of companies is to reduce material and intangible costs, to increase production time, and due to the quantity of products produced. There are many methods to reduce costs. One of the methods used by companies is the rapid changeover of SMED equipment. The purpose of the work is: Studying the method of rapid equipment changeover.

· Study of theoretical material on this topic

· Analysis of the practical application of the method of rapid equipment changeover

· Formulation of conclusions

Fast equipment changeover

Rapid equipment changeover is a concept for organizing the process of equipment changeover/retooling, which allows you to significantly reduce the time spent on equipment changeover.

The concept originated in Japan in 1950 at machine-building factories, the author of the concept is Shigeo Shingo, who developed this concept for 20 years (1950 -1970).

Assuming that any changeover could be accomplished within 10 minutes, he called his concept SMED.

The main purpose of using this tool is to minimize the batch size produced between changeovers.

SMED system is applied

1. To change the product range,

2. For quick changeover of production lines,

3. To reduce production downtime and increase the flexibility of the production process.

The tool is based on a fundamental division of the actions performed during changeover into internal and external:

· Internal adjustment is part of the operations of the changeover process that are performed when the equipment to be adjusted is stopped.

· External changeover is part of the changeover process operations that are performed during the manufacture of suitable products on equipment that is subject to adjustment.

The implementation of the SMED system includes:

1. Careful study and analysis of actual conditions in the workplace. The entire changeover process is timed (from the moment the production of product “A” is completed until the production of product “B” begins), all actions are recorded in great detail (picked up, secured, moved, etc.). It is recommended to record the current changeover process on video for ease of subsequent analysis.

2. Separation of actions into internal and external changeover. At this step, an analysis is carried out: all recorded actions are classified into internal and external, as well as into those that must be done before the equipment stops, during the stop and after it.

3. Convert (where possible) internal changeover activities into external ones. The analysis continues, identifying those actions that can be performed without stopping the equipment (pre-assembly, adjustment, warming up, preparing tools, equipment, etc.)

4. Simplification and streamlining of all elementary internal and external changeover operations based on their detailed analysis. Developing solutions to eliminate adjustments, settings, performing simplified fixations, organizing parallel execution of work, etc. This step may require modifications to the design of tooling and fixtures, which may require a significant investment. Also developing solutions to improve logistics (delivery of equipment, fixtures, tools, etc.), improve service, reduce movements, etc.

5. Documentation of new procedures and actions. Development of an operations improvement map.

If necessary (if the changeover takes more than 10 minutes), repeat all steps again.

Thus, through simple logical analysis, even without investing in redesign or fabrication of fixtures (fasteners, etc.), huge potential for improvement can be discovered in any changeover process.

Even carrying out the simplest analysis with maximum transfer of internal work to external work and standardization of the result helps to significantly reduce changeover time and stabilize the process.

Despite the existing myth that the implementation of this tool requires absolutely no costs, it is rightfully the most expensive, since a significant part of the potential for reducing changeover time is realized by changing the design (fasteners, fixtures, etc.), i.e. after investing certain funds.

The result of the analysis and decisions made should be a changeover standard that clearly regulates the sequence of actions, setup and startup parameters, the required time and means for its implementation (tools, equipment, etc.). Of course, the standard of changeover execution must be supported by managers, i.e. Managers must ensure that nothing prevents compliance with the standard and monitor compliance with it.

Key points to pay attention to when using the described tool:

· Definition of clear goals and required work results. Frequent mistakes - improvement for the sake of improvement, or spending time and money to reduce several hours of work for the adjuster. It is necessary to remember the main purpose of the tool and clearly understand the required result before starting work.

· Feasibility assessment. During the analysis stage, it becomes clear what potential can be released as a result of the work (how much changeover will be reduced), as well as what investments this will require. It is necessary to ensure that the required investment is worthwhile by comparing the effect of rapid changeover and the planned costs.

· Training and correct sequential adherence to each step. It is necessary to make sure that the team clearly understands the sequence of steps being performed, and should not skip or shorten any step.

· Standardization of the result completes any improvement. The result must be standardized, and the standard must be clear and precise.

· Formation of habits and control over compliance with the standard. Managers must control the standard and employees must follow it.

The results of work using SMED should be:

1. Standardized optimal sequence of actions when performing readjustment, including preparatory work, directly changing equipment (tools).

2. Standardized changeover time.

3. Standardized places and methods for transporting equipment and performing external operations.

4. Reduction and standardization of batch size and product inventory levels as a result of an increase in the number of changeovers.

Fast changeover provides production flexibility and reduces losses associated with:

· overproduction;

· excess stocks;

· downtime of equipment and operators.

This method, like any other, has its advantages and disadvantages.

Advantages: Reducing equipment downtime, minimizing inventories, focusing on production in small batches or to order, quick adaptation to changes in demand.

Disadvantages: Requires long-term discipline and significant change management skills.

The frequency and duration of trial runs and adjustments depends on the qualifications of the installation engineer.

Source: "News in detail. Newspaper of the Novosineglazovsky village", October 2013.

We thank the OMK Press Center for providing this material.

- Who is developing standards for retooling and how is the implementation process going?

A working group, which includes a senior site foreman, a worker, a site technologist and a standardizer, creates a standard - a document that is located at the workplace.

Before standardizing changeovers, it is necessary to set a specific goal - for example, to reduce the duration of the operation, improve the quality of the operation, stabilize time and quality. Next, the working group, using a certain procedure, forms a standard for changeover. At the same time, the working group must apply means of improvement, which we will discuss below. Then there is a stage of training ordinary employees to work according to the standard. The last thing is control over execution. At the moment, the second stage of the “Standardization of Operations” project is underway, within the framework of which standards will be introduced at key operations of production sites.

- How is this implemented in practice?

At section 1.1. we standardized the changeover on the CAB 300 welding complex. Based on the results of observations and timing, it became clear that the welder, in order to perform this technological operation, repeatedly descended from the platform, took the equipment, lifted it up, installed it, and then repeated the same actions. Also, to fasten the equipment, the worker had bolts of different diameters, difficulties with fastening the bolts, etc. The most optimal solution is to place the equipment within walking distance of the operator, to organize the work whenever possible, without the involvement of an overhead crane. In addition, you can use standardized equipment fastening parts. For example, when installing equipment A, one type of bolts and nuts is required, when installing equipment B - another, when installing equipment C - a third. It takes a very long time to find sets of these bolts and nuts, as well as tools. In this case, for all types of equipment, you can use unified fasteners, which require one type of tool.

For example, the unification of equipment is very important in order to reduce the variability of fastening pipeline connecting parts (CPF). The simplest thing is to reduce the length of the thread of the mounting bolt. For example, the time to tighten one bolt is 5 minutes, but if there are 20 of these bolts, it turns out to be 100 minutes? In this case, the idle rotation of the bolt is 3 minutes, and 2 minutes for tightening. It turns out that if we eliminate idle movements, then it will take 40 minutes to tighten 20 bolts. Accordingly, 60 minutes were saved. This is the simplest example of how improvements can be applied during changeovers - eliminating technological and organizational losses.

- By what principle do you select operations to which technological changeover needs to be applied?

The plant is implementing the organizational project “Production Flow”, within the framework of which maps of the flow of product manufacturing at each site have been developed. From these, operations that are a bottleneck or theoretical bottleneck are determined by calculation. This is clearly seen when, at a certain stage of product manufacturing, there is excessive storage of semi-finished products. We have identified a register of such operations that require standardization and created a schedule for the development of standards, which is carried out by working groups and updated monthly.

- How else can you reduce changeover time?

You can reduce the time for changeover as much as possible by investing and purchasing new equipment and accessories, spending millions of rubles. But you can go through standardization - and we try to simplify the procedure as much as possible without huge investments. There is a third option - to launch a constant process of improving the changeover standard, while involving the workers themselves in this procedure, because only they know all the pros and cons of their activities. What we've found is that most people care about what they do. Accordingly, find out from them what shortcomings there are and eliminate them. As a rule, this requires minimal investment and achieves high results. This work to improve standards is also planned as part of the project.

- What effect is predicted from the introduction of retooling standards?

As intermediate results show, by standardizing changeovers in some key operations, it is possible to reduce the duration by 25-30%, or even more - this means that we can produce more products, and, accordingly, earn more. We described in detail all the operator’s steps, ensured maximum reduction of unnecessary transitions and described the sequence of personnel actions, the use of the necessary tools, developed measures to increase the productivity of changeovers, etc. As I see it, it is now necessary to launch a procedure for training employees, the process of introducing improvements to working standards, and to achieve stable implementation of standards in each work shift.