Читать книгу TPM Reloaded - Joel Levitt - Страница 8
ОглавлениеTPM is a program for production (or operations in a power plant, for example). It is a manufacturing (or operational) strategy. In a TPM shop, operators are king of the hill. Without operation’s full, complete, and unwavering support, evidence of the TPM program will be hard to find a year after installation, or even less. The word Maintenance in TPM seems to scare operations people away. If TPM is implemented by or even initiated by the Maintenance department, it will fail.
When we say operations, we mean operators, supervisors, production control personnel, managers, and everyone else all the way up to plant managers. The TPM point of view must be the lifeblood of the productive effort and understood by everyone, especially the middle managers. To a large degree, the active support and at least cooperation of the middle management is the most essential element of a successful TPM installation.
The support of production control (production scheduling) is essential because they have to add TPM time into their schedules. Supervisors are essential because initially the TPM tasks have to be assigned, and managed so they are actually done.
Why Is This?
I was training the operators in a large precision stamping factory about TPM. They were excited because they got to finally address issues that had been bothering them, in some cases for years. We made great strides in cleaning the machines and realizing production gains.
The first phase of the training was complete. The team was supposed to continue the TPM activity in the pilot area and gain enough expertise to roll the program out to other areas. But as soon as I left, the production supervisor told the operators, “Well, that was fun, but now it’s time to get back to work.” In some cases, the supervisors were harder to sell (and more important to sell) than either top management or the operators. When I returned, we had to start over almost from scratch — with the added morale problems — with the formerly excited operations group.
Production Incentives
The last issues concern production incentives. TPM will increase production after the losses are identified and either eliminated or mitigated. During that transition, production might fall for a time. Production incentives have to be adjusted so that performance of the TPM tasks is covered by the incentive program. Otherwise, TPM activity takes bonuses out of people’s pockets (in the short term) and will be sabotaged.
So, if you are maintenance professional, this book can help you understand your important role in TPM. But, this book is for your production counterpart.
TPM (Total Productive MaintenanceJ) focuses on the barriers to higher production (Exhibit 1-1).
It’s simple to describe, but not necessarily simple to do!
We want to get more production at a lower cost out of our existing asset mix by eliminating waste (Lean Maintenance), managing production losses (TPM), and reducing variation in the production process (Total Quality Management). We also want the plant to be safe, nimble, flexible, and a good place to work.
Exhibit 1-1 TPM is Very Simple
Why the Results from TPM Are Urgent Today
A new situation has developed in the way we look at organizations. Throughout the last 25 years, organizations have slashed their ranks, reduced overheads, and optimized processes. This process accelerated at the end of the 2000s with the economic crisis. At the same time, we increased the complexity and speed of the equipment and our reliance on computers, programmable logic controllers (PLCs), and sophisticated controllers. We are faced today with smaller crew sizes — and basic maintenance demands are going unmet. Yet basic maintenance continues to be essential for reliable performance.
Superficially, TPM recruits operators into the maintenance function to handle basic maintenance tasks and become both the champions of their machine’s health and the tinkerers to reduce production losses from all sources. Operators become involved in maintenance activity (as well as other areas to detect and mitigate the losses) and decisions. TPM uses the operators in autonomous groups to perform all the routine maintenance, including cleaning, bolting, routine adjustments, lubrication, taking readings, start-up/shut down, and other periodic activities.
This might sound ungrateful (based on the fact that operations personnel work very hard and are proud of what they have accomplished), but at a deeper level TPM is designed to wake up operators and their supervisors as well as everyone up the chain of command. Many people sleep walk through their day and stop seeing the waste right in from of them. That is just not good enough anymore. TPM along with Lean Maintenance, TQM, and RCA (Root Cause Analysis) are complimentary programs that try to get full engagement from the operators and supervisors. With full engagement, success is possible.
The reason for this sleep walking is psychological. The single biggest barrier to identifying waste is called “the normalization of deviance.” This is a fancy way of saying that if you look at a pile of junk long enough, you’ll stop noticing it. The pile begins to seem normal. This tendency is the bane of operators (who stop seeing minor jam-ups and other missed opportunities), PM inspection (when people stop seeing deterioration), and lean maintenance efforts (when people stop recognizing waste).
Sometimes we have to shake up our normal methods of seeing. TPM is first an extended class in seeing and investigating our productive effort, and second a continuing alarm clock to awaken the producers. But make quick productive use of your altered sight — in a day or two, most you slip back to being blind to the waste.
The maintenance department becomes an advisory group to help with training, setting standards, doing major repairs, troubleshooting, and consulting on maintenance improvement ideas. Maintenance departments are the specialists in major maintenance, major problems, problems that span several work areas, and trainers. Under TPM, maintenance becomes very closely aligned with production. For TPM to work, maintenance knowledge must be disseminated throughout the production hierarchy.
The old philosophy of “Produce at all costs, damn the torpedoes — full speed ahead!” will fall flat on its face with TPM. TPM needs some downtime in order to be successful. The operators must have complete, top level support throughout all phases of the transition and thereafter.
Good maintenance practices, as highlighted by the article in Exhibit 1-2 on the following page, can contribute to the productive output and profit of the whole organization. It contributes to safety too.
TPM is revolutionary. It is a game changer on factory floors of organizations that can go all the way to autonomous maintenance. The ideas of TPM are to make the operator a senior partner in the production effort. These ideas, imported from Japan, have taken root in factories, refineries, mills, and power plants throughout North America. They succeed because they force us to realize we have to use more and more of the capabilities of every employee (and vendors too!) to remain competitive. Operators are traditionally viewed as underutilized in most factories.
Exhibit 1-2
The machine operator is the key player in a TPM environment. Many of the losses are under the control of the operator, involve the operator, or happen while the operator is near the machine. There is less reliance on the maintenance department for basic maintenance (but more for maintenance prevention projects, productivity improvement projects, coaching, training, problem solving, and mentoring). Control and responsibility are passed to the operators.
Although the operator is the key player, it’s the management that ultimately has to make the right choices. Keith Rimmer, a consultant from the global consultancy Woodhouse Partnership, says convincingly that for a company to be successful in Asset Management, “It requires processes that are driven effectively by top management and supported by empowered and competent employees. A key characteristic of successful asset management is consistently making sound decisions and good compromises, and carrying out the appropriate tasks at the right time and at the optimum level of expenditure. Above all it requires the commitment of top management, and it is unlikely that an organization will successfully integrate and optimize their asset management without such commitment.”
One interesting side effect was the application of TPM principles to complex process environments such as power plants, sewer treatment and water plants, and chemical plants. The operator of a sewer treatment plant is a very different person than the operator of a machine. The sewer plant operator has studied for and obtained a license. These positions generally require personnel with higher qualifications than do machine operator positions. Some of the same ideas can be applied, but the tasking has to be reviewed by personnel knowledgeable about both plant operation and maintenance. In a later section we will review the reason TPM was developed in automobile assembly plants and not in other business types.
Legitimate Fear
In today’s cut-happy environment, any change is viewed through the lens of job loss. TPM is no exception. When Paul Wilson, Managing Director of Aster Training, installed a TPM system, his team had to face fear from the maintenance ranks. He said, “We worked hard at alleviating any fear the maintenance technicians might have had that their jobs were under threat. This soon evaporated once we were challenging them with more interesting projects.” Much of the work being taken over by operations is not being done at all (like basic maintenance activity). Maintenance departments will find themselves with ample work on just the projects requested by the TPM teams. These projects will generally reduce waste, make the machinery operate better, or achieve lower levels of product variation. The result is better profit without personnel cuts (for the same volume). Of course significant cuts in volume will require retrenchment, but that is another conversation and should not be mixed up with a TPM implementation.
One of the leading thinkers in TPM is J. Venkatesh. His review of the history of TPM can be found in an article on Reliabilityweb.com. TPM is an innovative Japanese concept. The origin of TPM can be traced back to 1951 when preventive maintenance was introduced in Japan.
W.E Deming traveled to Japan under the Marshall Plan and began a powerful and eventually world-changing discussion about quality. The royalty of what was left of Japanese industry were in the training rooms. They saw that the drive for quality and efficient production was their only edge. They had no resources beyond what they could build and imagine.
The ideas of TQM (Total Quality Management) and the concepts of PM were only partial answers to the issues of maintenance and quality. After much trial and error, the PM effort evolved into TPM.
The concept of preventive maintenance was taken from American industrial practices. Nippondenso* of the Toyota group was the first company to introduce plant-wide preventive maintenance in 1960. Preventive maintenance is the concept where operators produced goods using machines, while the maintenance group was dedicated to maintaining those machines. However, with the automation of Nippondenso, maintenance became a problem as more maintenance personnel were required. So the management decided that the routine maintenance of equipment would be carried out by the operators. (This is the beginning of Autonomous Maintenance, one of the features of TPM). The maintenance group took up only the essential maintenance works.
Thus, Nippondenso, which already followed preventive maintenance, also added autonomous maintenance done by production operators. The maintenance crew was released of their routine maintenance tasks; instead, they carried out equipment modification for improving reliability and maintainability. The modifications were made or incorporated in all their new equipment. These tasks are aimed at maintenance prevention (MP). MP or Maintenance Prevention is the elimination or reduction in the need for maintenance. By reducing the source of the dirt, we also reduce the need for cleaning (an example of Maintenance Prevention). Thus, preventive maintenance along with maintenance prevention and Maintainability Improvement gave birth to Productive Maintenance (PM). The aim of productive maintenance was to maximize plant and equipment effectiveness to achieve optimum life cycle cost of production equipment.
By then, Nippondenso was using quality circles, involving the employee’s participation. All employees took part in implementing productive maintenance. Based on these developments, Nippondenso was awarded the Distinguished Plant prize by the Japanese Institute of Plant Engineers (JIPE) for developing and implementing TPM. Nippondenso became the first company to obtain the TPM certification.
TPM had become a part of TPS (Toyota Production System). According to Bob Williamson, a long-time veteran of the TPM wars, the TPS systematically focuses on the identification and elimination of waste to reduce manufacturing costs. In Japanese plants of that era, the culture was ripe for involvement of everyone in the production process.
In many ways TPM is a return to a pre-1920s model of maintenance. Before the 1920s, machine operators were skilled mechanics, so they were expected to repair their own machines. As mass production took over, lower-skilled operators were recruited and the production jobs became more menial. Many of these newly-minted operators were immigrants or just off the farm. Their greatest advantage was their lower wage rate and the long hours they were willing to work.
As the numbers of machine operators grew, the ability to fix one’s own machine quickly was gone. Company-sponsored training to improve one’s skills was non-existent. Soon this group, as well as management, forgot that these people had capabilities far exceeding those needed as operators. A tradition settled in of operators being only button pushers. The maintenance department as we know it developed at that early time by necessity, filling in with specialists in repairs and maintenance.
A new situation has developed in the way we look at organizations. For the last 35 years, organizations have slimmed ranks, reduced overhead, and optimized processes. At the same time we have increased the complexity and speed of equipment and our reliance on computers, PLCs, and sophisticated controllers. We are faced today with smaller crew sizes and greater maintenance demands than ever before.
TPM recruits the operators into the maintenance function to handle basic maintenance tasks and to become the champions of the machine’s health. TPM returns to the pre-1920 roots by re-involving the operator in maintenance activity and decisions.
The maintenance department becomes an advisory group to help with training, setting standards, doing major repairs, and consulting on maintenance improvement ideas. Under TPM, maintenance becomes more closely aligned with production. For TPM to work, maintenance knowledge must become disseminated throughout the production hierarchy. The operators must have complete, top-level support throughout all phases of the transition and thereafter.
TPS, (Toyota Production Systems) the Parent of TPM
TPM was the brainchild of Toyota. It was based on a component of the Toyota Production System. The production system had several parts. TPS (as it is called) is designed for a particular time, circumstance, and place. It was designed by people in tune with their culture and organization. Finally, TPS was specifically designed to manage the assembly of automobiles.
Machines to be Worked Upon
There are special attributes of automobile assembly that lend themselves to a TPM approach. The first item is that the tools are pretty small (compared to other industries such as steel making or mining). These relatively small tools meant that the operators could literally put their hands on the machine and learn something about its operation.
The second factor was that these tools and the processes used are not intrinsically hazardous (with a few expectations). This means that you might get hurt if you do the wrong thing, but it is unlikely that you will endanger others, like you could in an oil refinery or mine.
With the assembly tools being smaller, the need for elaborate sets of repair and maintenance tools and deep maintenance knowledge is not as important, especially for basic maintenance services. Finally, the machines are modular and quite sophisticated. When something breaks, usually an entire module is replaced.
The Employees
There are two aspects of auto assembly employees. This group is usually well paid and has low turnover. Low turnover is essential for TPM because of the training required. High pay means of the people attracted to factory work, the top tier is attracted to the automakers.
The Business System
In Japan most heavy, hazardous, and complex maintenance is done by contractors. The individual plants usually don’t have a deep or large maintenance department, except for a few mission critical services.
Of course, one big reason TPS thrived was that it was supported from the top of the organization. TPS permeated all activities of Toyota. It was patiently nurtured, revised, and improved until it entered the company’s DNA and it was expressed in most decisions made in the plant.
For these reasons, TPS was a logical system that was adopted and supported over a long period of time by Toyota’s management.
TPM, TQM (total quality management), Lean manufacturing, Lean maintenance, and JIT form the basis of the Toyota Production System (TPS). All of the programs dovetail together and support each other. In the end, the company produces high quality products with as few inputs as possible and as little waste as possible. For more information on this fascinating story, consult The Machine that Changed the World (bibliography).
The TPS House Graphic
“One of the most recognizable symbols in modern manufacturing is the ‘TPS House’ diagram as shown below. The diagram (Exhibit 1-3) is a simple representation of the Toyota Production System (TPS) that Toyota developed to teach their supply base the principles of the TPS. The foundation of the house represents operational stability and has several components, one of which is Total Productive Maintenance.” From an article by David McBride at the Reliable Plant web site (for the complete article, go to: http://www.reliableplant.com/Article.aspx?articleid=8417).
Exhibit 1-3 The TPM House
The house graphic shows the relationship between all the parts that make up TPS. It also shows TPM to be a foundation activity necessary for success. The results are the roof which when achieved becomes a competitor killer!
The Toyota system is designed to remove waste from the production of automobiles. It is interesting that the Japanese words become like Zen koans (stories) that disciples study to understand the mysteries. In this case, the Japanese words identify a type of waste. For example one type of waste is overburden and the Japanese word is muri. The waste associated with doing things differently each time (inconsistency) is called Mura.
All types of waste are called Muda. The challenge is designing a process capable of delivering the required results smoothly; by designing out “mura” (inconsistency). The design ensures that the process is as flexible as necessary without having to overproduce “muri” (too much work-in-process or overburden) since this generates “muda” (waste). There are seven kinds of muda that are addressed in the TPS:
1. overproduction
2. motion (of operator or machine)
3. waiting (of operator or machine)
4. conveyance
5. processing itself
6. inventory (raw material)
7. correction (rework and scrap)
The elimination of muda has come to dominate the thinking of many when they look at the effects of the TPS because it is the most familiar of the three to implement.
The entire organization is aligned to solve the most pressing problems that get in the way of high quality/ high quantity output. TPS has several sub-programs (of which TPM is one).
JIT
JIT is an advanced method of regulating production. Using JIT, only a small number of parts are made at one time. In some cases, it might be enough parts for 4 or 8 hours of assembly line production. These parts are replenished on a just-in-time basis. That means when the last part is assembled onto the product, a pallet of the next batch of parts is put down. The overriding issue is that when the machine is needed, it had better work or the line will be shutdown in a short time (like 4 or 8 hours). High reliability and quick repair are essential elements of a JIT environment.
When Harley Davidson, the leading American motorcycle maker, became an independent company, its management decided that JIT manufacturing was the best solution to the quality problems they were experiencing at the time. The thought was with minimal part runs a quality fix would get onto motorcycles within days. They used to run months of parts at a time to optimize and amortize the set-up time. Under the old plan, it might be months before the parts and subassemblies in stock were used up and the improved part appeared in bikes.
Motorcycles were assembled in York, PA, and the engines and transmissions were made and assembled in Milwaukee, WI. The truck of engine and transmission assemblies was supposed to arrive when the York plant got down to a shift of stock. In other words, if the truck delivering the engines was more than 8 hours late, the York assembly line would have to shut down.
Now imagine running JIT with equipment that was only 70% reliable. Three times out of 10 the equipment would be down when you needed it to produce parts.
“Total productive maintenance (TPM) is indispensable to sustain just-in-time operations,” says Dr. Tokutaro Suzuki, Senior Executive Vice President of the Japan Institute of Plant Maintenance in TPM in Process Industries. In a JIT system, he emphasizes, “You have to have trouble-free equipment.” Prior to the adoption of TPM, Japanese manufacturers found it necessary to carry extra work in progress (WIP) inventory “so that the entire line didn’t have to stop whenever equipment trouble occurred. The concept is that the operator must protect his own equipment,” he explains. “Thus the operator must acquire maintenance skills.”
However, maintenance experts may still make periodic inspections and handle major repairs. Design engineers also play a big role. They must take maintenance requirements — and the cost of equipment failure — into consideration when they design the equipment, stresses Dr. Suzuki.
Another Japanese Vocabulary Lesson
Using the Japanese language, TPM focuses the energy of the organization on the actual piece of work (gemba), the actual part (genbutsu) being made, and the actual activity performed or as the Japanese translation says phenomenon (gensho).
TPM directly attacks the sources of ineffectiveness by concentrating on all the sources of loss of production (not only on the maintenance-related losses). This is important because most mistaken impressions think the focus of TPM is on maintenance whereas the true focus is on high quality output.
Where Does Efficiency Fit In?
Most companies spend enormous amounts of money on improvements in efficiency. Efficiency is defined as doing things the right way. Industrial engineers spend a great deal of effort on insuring wasted movements are eliminated from the production process. TPM can be said to take the next step. TPM looks at doing the right things right. By attacking all of the losses, TPM insures that at the end of the day, the pile of saleable parts made by the process is bigger. In some cases, after TPM, the pile of good parts is a great deal bigger.
Where did the idea for TPM come from in your plant? As mentioned, if the maintenance department initiated the program, look out. It is difficult to convince anyone that the program is not just a way to off-load maintenance work onto operations. Related to this question is another: Who is driving the effort?
What difference does your situation make to the success of TPM? If your machines are large or hazardous, or they require enormous skill to even consider fixing, then traditional approaches to TPM will not easily work. The fundamental shift is not maintenance activity to operations (which everyone seems to focus upon) but the responsibility for all production losses shifts to operations.
How disciplined is your production effort?
Although not every company needs full TPM implementation, every company has something to learn from it.
* Manufacturer of auto parts and part of the Toyota group of companies. Was established December 16, 1949 as Nippondenso Co., and subsequently renamed DENSO. As of March 31, 2005, DENSO Corporation consisted of 171 subsidiaries (64 in Japan, 33 in the Americas, 31 in Europe, and 43 in Asia/Oceania) with a total of 104,183 employees. In 2006, DENSO was listed at #207 on the Fortune 500 list.
