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How maintainable are your assets?

Noria Corporation

In previous Reliable Plant columns, we've discussed the "three pillars" of lubrication excellence:

  1. making the right decisions through the application of sound lubrication engineering best practices

  2. documenting these decisions in the form of job plans and procedures; and

  3. training individuals to perform the prescribed tasks.

An effective lubrication maintenance program should be built around all three pillars and characterized by properly engineered tasks based on either a prescribed time interval (preventive maintenance) or on some predictive tool (condition-based maintenance), be it a visual inspection or a technology-based means such as oil analysis or vibration analysis.

Unfortunately, too many plants adopt a simple "PM schedule," where the frequency of lubrication tasks is based on production schedules rather than maintenance best practice. The results are less-than-ideal lubrication PM task intervals and an almost impossible job of developing an effective condition-based program. There are often good reasons for this approach. For many plants, depending on how the facility and its assets are designed or operate, it may be difficult/impossible for even the most skilled, well-intentioned technician with the most well-designed program to perform required tasks. The machine can't be maintained while running, and is not shut down to allow for maintenance!

Take, for example, the greasing of a simple pillow block bearing. Particularly for higher-speed applications, it is imperative that the bearing be greased while it's running. However, in my in-plant consulting activities, I frequently observe a grease fitting that can't be accessed while the machine is running, an optimum regrease frequency of one to three months and an annual (scheduled) outage frequency of 12 months. Under this scenario, it is humanly impossible for anybody to do "the right thing."

I'm not suggesting that we disrupt production schedules or implying that in-plant or OSHA safety rules are overbearing. Rather, my point is that, in many cases, little thought or consideration is put into equipping machines for normal, in-service maintainability when new or rebuilt equipment is put into service.

Simply stated, maintainability refers to the ability of plant personnel to maintain any asset during "normal" operation of the plant. In this example, all it would take for this asset to be maintainable is for a grease supply line to be extended to a safe working location, or if the expense or application warrants its use, the installation of a single- or multiple-point automatic grease dispensing system. Extending the grease line is a simple fix (when the machine isn't running). But in other instances, the required design or configuration change is a little more exacting, to the point where it may never be done, always being "deprioritized" as shutdown maintenance tasks take higher priority.

In the past several years, I've helped develop and design lubrication PM and PdM programs for new plants and, in one instance, a plant that was still an empty shell with little more than an asset list. In each case, the engineering team involved in plant design, procurement and commissioning paid little to no heed to how the maintenance and reliability engineers would actual maintain the equipment - to the point where machines are set up to repeat the same cycle of poor maintainability, poor reliability and premature failure we typically see in older, established plants. This is what Albert Einstein called the definition of insanity: "doing the same thing over and over, expecting different results."

So, how do we insure maintainability and avoid insanity? The ideal time to properly equip machines is during the design, engineering and commissioning of a new plant or asset. Failing that, it's imperative that if a plant is truly going to achieve lubrication excellence, it must conduct a detailed survey of all assets and develop a game plan for making necessary modifications and changes. For modifications that can be made "on the run" (e.g. changing to a high-efficiency breather or air filter, adding quick connects to add oil via a filter cart, etc.), the plant should put a plan in place to immediately implement the prescribed changes. For plants that require the machine to be shut down, the production and maintenance planning and scheduling departments should develop a schedule and plan to insure that the modification can be made during the next available window of opportunity.

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