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
