In many organizations, groups are often trying to chase the latest buzzwords of the day and yet have never established the foundation required to support those efforts. PM development and execution are classic examples. For this discussion, when I refer to PMs, I am talking about both preventive maintenance and condition-based maintenance tasks. This is by no means an exhaustive explanation of all of the considerations necessary for a comprehensive PM program. It is intended as a rough guide to foster continued discussion into the topic.
- Stop doing non-value added PMs or task steps within the PM. We can never seem to find time to update or correct the PM tasks or frequencies but can always find time to continue doing the wrong work (go figure! ).
- Assuming that you already have a PM program in place, start with the equipment where you are bleeding or hemorrhaging the most. This is often not your most critical assets.
- Identify the failure modes of the equipment. The blowout preventer in the Gulf oil spill had more than 260. Per the SKF manual, a bearing has more than 50 failure modes.
- Use the Reliability-Centered Maintenance Logic Tree to determine the tasks. Use condition-based monitoring (CBM) techniques where possible first because it’s less expensive, especially compared to an overhaul. Yes, some groups still do overhaul maintenance for no other reason than they have done it that way for the last 20 years. Your equipment actually defines the type of PM, as not everything lends itself to predictive technologies, as an example. Run to failure is an option, provided you can limit the collateral damage. CBM often extends or widens the failure detection window over time-based activities.
- Define tasks that allow you to find the equipment in the act of failure with respect to each of the failure modes. Failure modes and effects analysis is a great tool for these items, but many groups can’t seem to find the time to perform them in developing their procedures.
- Create the procedures using standard text.
- Focus on precision maintenance to a specification (i.e. torque values, belt tension).
- Be sure to look for hidden failures.
- Set the frequency of the task based on experience and history, if you have it. Generally, in very broad terms, it should be one half the width of the failure detection window. Keep in mind that you need time to effectively plan and schedule the equipment restoration in a proactive manner.
- Inspect and audit the work processes.
- Measure the outcome and benefits.
- Solicit feedback from the crafts performing the PM tasks by adding a continuous improvement loop.
- Great procedures are a start, but recognize that you may need to focus on changing the behaviors of the people who are doing the work. The behaviors may be as much as 80 percent of the work.
- Establish partnerships with the other stakeholders such as production and engineering. As an example, it’s hard to do the PM when production doesn’t give you access to the equipment. No matter how well you maintain it, if the equipment is not operated correctly, no level of maintenance can keep it running. If engineering bought the least cost equipment and installed it with poor methods, you most likely can’t overcome that either. Realize the total life cycle costs (LCC) may be upward of 20 times the initial installed cost.
- When you have a failure, you should perform an autopsy to determine why the equipment failed. Review the task procedures and frequencies to determine why you never caught the failure mode in the act of failure. Update the PM based on the findings.
About the Author
As a managing principal for People and Processes, Jeff Shiver helps organizations implement best practices for maintenance and operations. Prior ...
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