TPM for Workshop Leaders

Shirose Kunio

• Publisher: Routledge
• Year: 2017
• Topic: Business
• eBook ISBN:
  9781351407441
• Subtopic: Operations
• Index: Business

Workshop leaders play a central role in your company's efforts to implement TPM. Once your workers have been divided into small groups to learn the fundamentals of TPM, it is the group leader who spearheads ongoing training and implementation activities. With quick-reading, people-oriented practicality, this new book addresses the role of the workshop leader in maximizing the benefits of TPM.A top TPM consultant in Japan, Kunio Shirose: Incorporates cartoons and graphics to convey the hands-on leadership issues of TPM implementationUses case studies to reinforce his ideas on training and managing equipment operators in the care of their equipmentItemizes specific activities that must be undertaken to search out, correct, and control defects to remedy equipment shortcomings.He also addresses the cooperative relationship necessary between maintenance and production and leaves you with an understanding of the three imperatives for successful TPM implementation to change the quality and functioning of the equipment, the way operators think about equipment, and the workplace. (Originally published by the Japan Management Association.)

1

Causes of Breakdowns and Defects

Chronic breakdowns and defects have many causes, one of which is people, as the following example illustrates.

A worker reports to the group leader that an equipment breakdown has stopped production. Although the leader is very concerned about meeting delivery schedules and is understandably upset by the frequency of this type of breakdown, the production line obviously had to be stopped to deal with the problem. A maintenance worker is called in, and after some troubleshooting, reports the damage is serious enough to warrant replacing certain parts. However, there is some uncertainty about their availability, and downtime could be as much as four or five hours, especially if the parts had to be fabricated.

As a temporary measure, the leader decides to shift production to another machine while the repairs are being made. At this point, the maintenance worker says, “You know, this breakdown didn’t happen just out of the blue. I’ll bet this machine’s been acting funny for at least two or three days, and this part was probably vibrating or making a strange sound. You guys should have told me about this sooner. I could have fixed it in about ten minutes during your lunch break. Please let me know as soon as you notice anything strange about any of these machines, OK?”

The leader agreed, but added it was obviously the responsibility of the maintenance department to teach the operators how to recognize the early signs of these problems. This seemed like a good idea, so they decided to set a meeting time.

After thinking a moment, the leader realized this was not a long-term solution and said, “But why does this kind of breakdown happen? Sometimes there are certain parts that are always breaking and other times, like today, some other part suddenly breaks. We don’t know if it’s because we’re using the equipment wrong, or if the equipment itself is bad, or if the maintenance procedures are no good. Whatever the cause, it sure fouls up our work!”

Believe it or not, there is nothing unusual about the situation just described. In fact, most workplaces suffer from this same dilemma. Breakdowns are the root of all problems, because when they occur, production stops, deliveries are delayed, and product defects are created; in other words, a single breakdown can wreak havoc throughout the factory and can “break down” the entire operation. That is why you must always seek to prevent them.

In this situation, the damaged equipment had been signaling its abnormal condition through unusual vibrations or noises. If the workers had read these signs and responded promptly, the breakdown could have been avoided; so the human factor was the root cause of the breakdown.

As a matter of fact, whenever you look deeply enough into the reasons for any breakdown, you invariably find people related causes. So if people are ultimately responsible for creating breakdowns, why shouldn’t they also be able to prevent them, creating a “zero breakdown” workshop? There are ways to reduce and even completely eliminate breakdowns, and one is the subject of this book: TPM (total productive maintenance).

A detailed definition will be provided later. For now, understand it as something practiced cooperatively by two groups of people: the maintenance staff, who act as “equipment doctors,” and the production staff, who work with the equipment every day.

In particular, the equipment operators need to be taught how to discover abnormalities so they can identify problems early on. For their part, the maintenance staff must apply their specialized skills to analyze equipment data provided by the production department, find the causes of breakdowns and abnormalities, and take effective measures to prevent the recurrence of similar problems.

The road to achieving zero breakdowns starts with daily equipment checks and other maintenance activities performed by the equipment operators themselves, as well as specialized activities performed by maintenance workers.

Here is another example of a workplace situation:

One day a group leader notices the equipment operators are doing a lot more rework than usual. When asked why, one operator replies that nothing has changed in their procedures, but when they use certain material lots, the percentage of pieces needing rework seems to increase from tht norm of 2 or 3 percent to 5 or 6 percent. The operator believes the problem is with the material lot.

The group leader agrees that things always do seem to change for better or for worse each time a retooling is performed but also suspects problems with the equipment. So, of course, there are questions about what repair measures had been taken in the last week to try to correct the problem. The operator describes how a new grinding wheel, installed two days ago, did seem to correct it, but only temporarily. Then they increased the processing speed and did an extra careful job of retooling, during which all the changeover parts were precisely measured, but they still found the machine problematic.

After a moment’s thought, the group leader suggested the grinder spindle might be wobbling too much and that the operator should look into that. A check revealed that, indeed, this was the case. So the leader was satisfied they had found the cause and told the operator to have a maintenance person repair the spindle the very next day.

In this situation, the operator was constantly having to make repair adjustments, and each one was successful for only a short time.

Why were these repairs so unsuccessful? Because they each addressed a different cause, and there were several causes for the malfunction.

For example, the precision of equipment can be measured in three different ways — static precision, dynamic precision, and jig precision. Problems can be caused by one type of imprecision or a combination. Whatever the cause, the operator or maintenance worker must respond with reworking.

These types of problems are likely to occur in any workplace, and when they do, they can lead to major production problems. What can be done to prevent them? To escape from the vicious cycle of problems and their causes, make a thorough study of all imaginable causes and then carry out an equally thorough set of responses.

The preceding example showed how making single repairs here and there does not reduce chronic defects. The only way to get rid of chronic defects once and for all is to be systematic and to prepare a list of all the probable causes, then do whatever is necessary to eliminate every single cause, no matter how minor.

It is not easy to understand the importance of this systematic and thorough approach; therefore this topic is discussed in more detail in Chapter 6.

THE WORKSHOP ENVIRONMENT

What conditions promote breakdowns and defects in typical workshop environments? To answer this, it is necessary to study overall workshop conditions in the belief that whatever these may be, they are symptomatic of the basic attitudes of the people who use the workshop. As you read the following lists, consider which conditions exist in your own workplace.

Condition of Equipment

• The equipment is generally very dirty.

• Cutting debris is scattered on and around the equipment.

• The equipment leaks hydraulic fluid and lubricants.

• Cutting oil is scattered around.

• Oil pans are overflowing.

• People don’t mind seeing dirt and grime piling up everywhere: they think it’s normal.

• Grime from the cutters and grinders is caked onto the equipment.

• Motors are coated with a layer of oil mist.

• Motors are allowed to get very hot, or they often make strange noises.

• The limit switches on the cutters and grinders are covered with oil.

• Large covers are sometimes used to protect certain machines, but their internal parts are not cleaned.

• A broken V-belt is not replaced on a machine that uses three belts. Instead, the machine is allowed to operate with only two belts.

• Some parts rattle and vibrate.

• The equipment is positioned to make access for routine maintenance checks difficult.

• Oil cans are left empty and dirty.

• Drains are clogged.

• Wires and pipes are left in chaotic configurations, making it hard to see which one goes where.

Condition of Area around Equipment

• It takes a lot of time to recover cutting debris.

• The cutting debris is scattered around so it takes a long time to sweep up.

• There is no stand for the oil cans (and the oil equipment is left dirty).

• The floor is left dirty and, in spots, slippery with oil.

• The jigs are not kept tidy and organized.

• There are a lot of useless items lying around.

• Things are not kept in specified places.

Equipment Operators

• Operators occasionally mak...

Table of contents

• Cover
• Half Title
• Title Page
• Copyright Page
• Table of Contents
• Preface
• Publisher’s Message
• 1 Causes of Breakdowns and Defects
• 2 Definition of TPM
• 3 Characteristics and Goals of TPM
• 4 Approach to Equipment Efficiency Improvement
• 5 Loss Calculation Methods and Improvement Targets
• 6 Approach to Chronic Loss Improvement
• 7 Autonomous Maintenance Activities of the Production Department
• 8 Planned Maintenance Activities of the Maintenance Department
• Afterword
• About the Author