Money spent on maintenance ultimately does not contribute to the final product – lumber, pallets, etc. However, without maintenance, machinery failures will lead to higher costs and more unplanned downtime.
Workers in the forest products industry are constantly reminded of how difficult it can be to keep equipment well maintained and running as they try to sustain high production volumes yet reduce overall costs. This difficulty has increased in the economic slowdown.
However, unexpected downtime always results in both higher costs and reduced production. Often, traditional maintenance programs cost more in the long run than a preventative maintenance program.
Richard Baldwin, author of Managing Mill Maintenance (1990), stated that, “Equipment and facilities management, with an annual price tag in the billions of dollars, is probably the most talked about and least understood management task.”
In the next two columns we would like to introduce the concept of preventative maintenance systems and how to start implementing one.
Management often views mill maintenance with the belief that money spent on maintenance is a necessary evil: It needs to be done in order to keep machines running to produce, but costs should be minimized whenever possible.
Money spent on maintenance ultimately does not contribute to the final product – lumber, pallets, etc. However, without maintenance, machinery failures will lead to higher costs and more unplanned downtime. The cost of overtime for repairs and the extra expense to obtain parts rapidly is often excessive. In addition, there are increased potential safety issues associated with lack of maintenance.
We believe there are three basic maintenance systems in use today:
1. ‘Fix it when it’s broke’
A system, but one of delays, confusion, lost time and money.
2. Traditional Maintenance Planning and Scheduling
A dedicated, separate top-down driven department.
3. Maintenance Systems
Bottom-up-driven with upper level support; an example would be Total Productive Maintenance (TPM).
Each of these approaches can work well in any manufacturing environment given the right goals and priorities. However, maintenance systems, if implemented properly, usually lead to significant reductions in downtime and overall operating costs.
The opportunities can be demonstrated in Table 1, which shows the benchmarks of downtime, overtime and planned maintenance and cost of sales for various industries.
The first column shows the results of an informal survey of primary manufacturers in Virginia. The second is for all overall industry (not just forest products), and the third is for world class industries, which would be the ideal manufacturing state. The percent of unplanned downtime and maintenance overtime decreases and planned maintenance increases as we move towards world class industry.
Research has shown that most breakdowns are preventable and are a result of deterioration that could be detected as a change in machine performance or condition. One of the goals of a maintenance system is to share responsibility for equipment reliability. The maintenance department is no longer solely responsible for detecting problems and fixing them. Operators are trained to detect when problems begin to occur and to provide basic maintenance operations to keep equipment functioning properly.
Maintenance workers shift to providing technical support to operators; they help train operators yet still perform major equipment repairs and overhauls. They work to improve preventative and predictive maintenance and equipment performance. By assigning the responsibility of basic equipment checks and maintenance to operators, the maintenance workers now have more time to spend on more difficult tasks, the ones they are trained to do.
Operators begin to have more ownership in the equipment and a better understanding of how the equipment can work more effectively. They report equipment abnormalities before they become machine center failures. Visual queues are used to insure that maintenance is done and that extra paperwork is not required.
The goals of a maintenance system are to:
—reduce maintenance costs
—eliminate equipment downtime
—achieve a safe, clean workplace
—provide proper training and open communication
—promote operator ownership of equipment
—measure maintenance performance
—sustain improvements and gains.
Total Preventative Maintenance (TPM) is an example of a maintenance system adopted by world class manufacturers. TPM programs are founded on five basic concepts. These are:
1. improving overall equipment effectiveness
2. basic equipment care
3. root cause and countermeasures
4. planned maintenance system
5. predictive maintenance
Improving overall equipment effectiveness involves identifying idling and minor stoppages which can become accepted as normal production processes, such as feed rates, loading and unloading, etc.
Basic equipment care involves teaching the operator basic equipment care, tracking mechanisms and installing visual queues for regular maintenance procedures and operating parameters.
Root cause and countermeasures looks at why things fail when they do and how to prevent them.
Predictive maintenance involves using methods to better analyze existing equipment to prevent future failures and problems. Examples are vibration analysis, oil analysis and thermal imaging.
To begin applying TPM concepts to plant maintenance activities, the entire workforce first must be convinced that upper level management is committed. Personnel must be trained on how to service, maintain, repair, and operate the equipment and see that they comply with the preventative maintenance program. Simple records should be kept, such as a running record for each machine, which includes: notations on part replacements, overhauls, breakdowns and documented performance and cost figures to guide future equipment purchases. Responsibilities have to be assigned and a system designed to insure that the appropriate measures have been taken without creating more paperwork. All levels of management, maintenance and operators should be involved in this process.
Implementing a Total Productive Maintenance program can be a difficult task. It requires that everyone be onboard with the program, from equipment operators to maintenance and management. Often some people may have difficulty with giving up control over some processes or accepting a new responsibility.
We recommend implementing a TPM program gradually so that people can begin to see the benefits before the concept is applied to the entire facility.
In our next column we will discuss where to start implementation of a preventative maintenance program.
(Editor’s Note: Brian Bond is an associate professor and extension specialist and Earl Kline is a professor in the Virginia Tech department of wood science and forest products.)