TPM for the Lean Factory

Innovative Methods and Worksheets for Equipment Management

Keisuke Arai

• Publisher: Routledge
• Year: 2017
• eBook ISBN: 9781351407472
• Topic: Business
• Subtopic: Industrial Management
• Index: Business

Lean manufacturing cannot happen in a factory that lacks dependable, effective equipment. Breakdowns and processing defects translate into excess work-in-process and finished inventory, kept on hand ""just in case."" Recurring minor stoppages force employees to watch automated equipment that should run by itself. TPM gives a framework for addressing such problems, but many companies implement TPM at a superficial level, and the resulting productivity gains fall short of their potential. If your TPM implementation has resulted in posters and logos rather than a rise of productivity, how are you addressing this halt of progress? In TPM for the Lean Factory, authors Sekine and Arai teach you to identify and attack the key equipment-related problems and misunderstandings that make plants miss their lean manufacturing goals.

Written for companies with a basic TPM framework already in place, you'll learn three powerful approaches for cutting this waste:

• The new 5Ss: focusing on standard locations and labeling through the first 2Ss
• Instant maintenance: mastering quick repairs of minor equipment failures
• Improved setup operations: organizing the preparation to save time and prevent errors

Chapters on cell design, product and process quality factor testing, and daily equipment inspection give you additional weapons for fighting waste and low productivity. For practical application, an implementation overview summarizes the steps for each topic, keyed to a set of 50 adaptable worksheets and examples. A practical and supportive resource, TPM for the Lean Factory extends a fresh vision and focus to help you get top results from your TPM efforts.

The Seven Types of Waste in TPM

1

Why TPM Now?

In recent years, TPM at many plants has turned into “display TPM.” It consists of plastering the walls of the plant with management graphs and telling the workers to look at them. The original style of TPM, however, was much more rough and ready.

In the mid-1980s, we led a study group from France around the Toyota plant in Japan. As we were walking past a transfer machine line, one of the motors began to smoke. Immediately, a whistle blew, a person who appeared to be the leader shut off the power, and two operators came running.

The leader swiftly issued some orders to the two operators and then began to remove the burned-out motor. By the time the operators brought the replacement motor, the bolts were already loose, and the team of three quickly got the new motor up and running. The members of the study group burst into applause. They were so astounded to see this direct approach that they stood transfixed, not even hearing their guide’s directions to move to the next area.

At their company, group members said, it took at least four hours and perhaps as much as a full day to replace the motor of a transfer machine. That was why they were so impressed at seeing the Toyota workers accomplish the task in a mere nine minutes.

This plant didn’t have a single management graph on its walls, but thanks to its well-trained workers, the rough and ready style of maintenance was alive and well. We were so impressed that we began calling this approach “instant maintenance.”

TPM has three basic foundations:

1. Everyday maintenance: Workers take care of their machines and production lines themselves.

2. Periodic maintenance: Certain maintenance tasks are scheduled to happen annually or semiannually, like a complete physical exam for machines.

3. Instant maintenance: Small problems with equipment are fixed within three minutes.

This third method is the most important one at the job site.

The Seven Types of Waste

A certain machine products factory, a medium-sized company, had a monthly output worth ¥100 million (approximately $800,000).^* At the beginning of 1990, top management made a momentous decision to construct a new plant and institute a high-priced form of factory automation (FA) within three years.

After a few months, the new plant was complete and was partly able to run on an automated basis. Machining precision improved, and the factory appeared to have undergone a revolution.

However, a closer look revealed that the company was using the new facilities in old ways. The younger operators took care of the automated operations, while the older operators merely ran single-function machines, just as they always had. They had no interest in acquiring the new technology skills, and they seemed unable to keep up with the changes. Despite their years of experience, they weren’t much help in supervising the younger operators, because their expertise was limited to one single-function machine. This meant that the lower-paid younger operators were several times more productive than the highly paid older operators. Furthermore, people stood in front of the automated machines and just watched them work, so more machines were idle than ever before.

Why did this happen? It was because most of the on-site managers knew only the old ways of using the new machines. In particular, since the FA equipment had to be continually reprogrammed, changeover took a long time, and mistakes in programming led to large numbers of defects. For that reason, only part of the work was delegated to the automated equipment and the rest was done on single-function machines or by hand.

In addition, the automated equipment sometimes broke down, leading to both major and minor stoppages. There were no personnel within the company who could maintain the FA equipment, so they depended on the manufacturer’s service representatives. This meant not only that their production technology did not develop properly, but also that their know-how flowed to outsiders, the efficiency of their equipment declined, production slowed down, and parts inventories increased. All these factors gradually led to lower quality and increased production costs.

The introduction of FA had failed to increase output. The company needed to raise the proportion of automated equipment, and the key to increasing efficiency was maintenance and retooling.

Most of the waste in this plant stemmed from incomplete implementation of TPM, as shown in Table 1-1.

The first fundamental source of these kinds of wasted effort is not installing equipment appropriate to the amount of production. This means, for example, producing small lots on specialized machines and producing large lots in machining centers.

Table 1-1. The Seven Types of Waste in TPM

1. Minor stoppages, medium stoppages, major stoppages

2. Lengthy setup times

3. Manual rework, defects, faulty products, and low yields

4. Planned downtime

5. Incomplete 2S application

6. Overproduction by large equipment

7. Equipment problems at production startup

The second source is rushing to automate fully without first introducing the simpler forms of automation. After all, even with automation, eliminating human workers is difficult. For example, even when you streamline the work so it requires only 0.3 worker, you still have to have one worker, but the other 0.7 of that person’s time is like excess inventory. This excess is the reason automation doesn’t reduce costs as much as it is intended to. The ultimate goal should be lowered costs, not just modernization of equipment.

The third source of waste is failure to automate changeover, even when the rest of the process uses automation effectively. This leads to deviations from standards and variations in product quality. When specialized lines undergo simple automation, it’s an easy process, but since changeover is performed by people, retooling the more complicated equipment takes a long time. Quality is a reflection of the number of processes. If changeover takes too long, it inevitably leads to mechanical breakdowns and defects.

The fourth source of waste is the lack of synchronization between processes. When process A is performed on high-speed equipment and process B is performed on low-speed equipment, unfinished inventory piles up between processes. For all practical purposes, unfinished inventory is useless inventory.

The fifth source of waste is a lack of mechanisms for ensuring that employees follow safety rules. Safety is determined by the number of safety...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Publisher’s Message
• Preface
• Chapter 1 The Seven Types of Waste in TPM
• Chapter 2 The 5Ss Begin with the 2Ss
• Chapter 3 A New 5S Example: Mynac Company Case Study
• Chapter 4 The Fundamentals of Instant Maintenance
• Chapter 5 A Case Study in Instant Maintenance
• Chapter 6 Improving Setup Operations
• Chapter 7 Eliminating the Waste of Planned Downtime
• Chapter 8 Eliminating Abnormalities within the Process
• Chapter 9 Promoting Daily Equipment Inspections
• Chapter 10 Test Yourself: A Lean TPM Quiz
• Implementation Overview for TPM Innovation
• Worksheets for TPM Innovation
• References
• About the Authors
• Index