More companies are embracing Total Productive Maintenance (TPM) as a means of keeping key machines up and running. TPM encompasses all of the key aspects of machine maintenance (reactive, preventive, predictive and so forth) with one key addition—it uses the skills of the machine operator to identify the need for maintenance early on.
TPM is a maintenance management program with the objective of eliminating equipment downtime. It focuses on overall equipment effectiveness, covering areas such as breakdowns, setups, the ability to maintain cutting tolerances, capacity and more.
Just about every company has resources to repair machines that break down. Most companies even have preventive maintenance efforts to increase the chances that machines will keep running. These efforts are calendar-based and include activities such as changing fluids, replacing filters and lubricating items that wear. They are performed regardless of need, often independently of one other.
When using calendar-based maintenance techniques, however, it is possible that we are either under servicing (risky) or over servicing (costly) our equipment. TPM helps us to provide precisely the correct amount of maintenance service on any machine.
TPM requires a partnership between many branches of the organization, including machine operators, manufacturing engineers and other technical service personnel, maintenance technicians, and even equipment suppliers. This partnership focuses on a long-term approach to machine performance, rather than just fixing problems. With TPM, machine operators must accept new responsibilities, such as daily maintenance checks, minor adjustments, lubrication and minor part changes. Even extensive overhauls and breakdowns handled by plant maintenance personnel should be assisted by machine operators.
TPM involves analyzing equipment performance and identifying the root causes of problems. Operator input is critical, as the operator knows the equipment best and is in an ideal position to analyze performance. Once the root causes of problems are identified, permanent corrective action plans must be established and implemented. Once a plan is implemented in one area, it should be evaluated for other areas of the plant, because problems that affect one type of machine frequently affect others as well.
The following steps are critical to an effective TPM program. Each can complement existing machine maintenance practices.
Collect detailed data on equipment downtime. When a machine is under warranty, equipment manufacturers maintain detailed service records of all maintenance calls. They do this to track machine performance and identify the most frequently occurring problems. In doing this, manufacturers are actually performing a type of TPM and using it to recommend future design changes to enhance performance.
We can learn a lesson from these manufacturers by keeping equally detailed records to aid in enhancing the performance of our machines. The records will vary by company, but at a minimum, they should include:
- Date of problem
- Description of problem
- Time the machine was inoperable
- Problem resolution steps
- Final solution
- Permanent corrective action plans
Ensure that the equipment is thoroughly cleaned on a regular basis, and that during this cleaning, critical components are inspected. Inspection through cleaning is an effective technique, as it provides a wealth of information with a relatively small extra effort. You are cleaning the machine anyway, so why not take the extra time to be sure everything looks good? Typical things to look for are cracks, wear marks, loose connections and leaks from fittings.
Create a team to manage the machine. This cross-functional team will take steps to ensure that the TPM plan remains on track. The team should also look into equipment that can identify problems before they occur. Equipment such as vibration analysis devices and noise sensors can be useful in predicting future problems.
Generate standards for cleaning, lubrication and replacement of filters and other consumable items. How frequent and detailed these are will depend on many things, including the machine's workload, age, recent maintenance history and more. Standards should also include a daily check of the machine, with critical items being reviewed to ensure good working order.
TPM cannot be implemented for free. Costs will be incurred but will be dwarfed by the results obtained from having your machines run often and effectively.