The Design and Commissioning Phase

Maintenance engineers commonly deal with the result of someone else's design - whether good or bad. When design is finished, construction starts and finishes, and the plant is commissioned. The Maintenance Engineer arrives someway through this (if he is lucky). Quickly he finds himself left with a maintenance budget being used to finish off construction / over-expenditure, a plant that is going through teething problems, spares arriving in dribs and drabs and little information about plant failure modes and the effect of failure. Rarely is the plant delivered to the maintenance department with a comprehensive and well-documented maintenance requirements analysis and a maintenance plan.

What happens in best practice organizations is that, amongst other things, a fully documented RCM based maintenance program is developed through the design phase. Unfortunately in the vast majority of capital projects in industry, any reliability engineering or failure analysis is done in an informal manner and certainly not provided to the maintenance department for use in developing asset management strategies and policies.

Post Commissioning

After commissioning, (or sometimes before) the design team disbands and its members find work on new projects. The Maintenance Engineer is left to second guess the design intent, the plant limitations, the potential failure modes, and the likely consequences of them. The operations people are, at the same time, learning how to operate the plant and experimenting with it; pushing it to its limits and occasionally well over its design intent. There is limited money or time to change obvious design or maintainability problems in the new plant.

The task of defining the plant maintenance policy¹ is a priority but a most daunting one. Whatever is achieved is done in a rush often using people in an opportunistic manner. The problems that emerge right from the beginning will be as follows:

• There is no consistency of analysis philosophy.
• Maintenance personnel, being risk averse, write maintenance policies which over service and use overhaul or intrusive methods as a means of prevention - often to the detriment of reliability rather than for its good² .
• There is no audit trail, and only those who wrote the policies know their rationale. It becomes near impossible to review the program and objectively assess its effectiveness.

Full Production

When the plant swings into full operation and breaks down, more maintenance tasks are created and some existing tasks are done more frequently. Many of these new tasks duplicate others. Often, in an attempt to be seen to be doing something about high profile reliability problems, maintenance personnel create and perform tasks supposed to prevent the failures but, in reality, serve no realistic purpose.

Soon the Preventive Maintenance (PM) requirements exceed the labor resource available. PM is missed, preventable failures occur and unplanned maintenance work consumes more labor than necessary. The number of temporary repairs grows out of control and the costs of revisiting them or repairing additional damage caused by them wastes more resources.

The vicious circle of breakdown maintenance, temporary repair, and reduced PM gains momentum and becomes well entrenched.

Management Consultants (often with a cost reduction focus) arrive on site and cut staff numbers and budgets. This serves only to tighten the vicious circle and increase the rpm. The end result is typically a large morale problem for the maintenance department and a poorly performing plant.

Many organizations have tried to regain control by using RCM to develop their maintenance program. This is often a pursuit with limited scope and a high failure rate. This is because RCM is highly inefficient when used as a rationalization tool. It consumes excessive amounts of the most valuable resources on site - those being the scarce maintenance and operations personnel.

A large element of the inefficiency of RCM, is that it does not acknowledge the experience and value of the current maintenance program. It starts from scratch and builds a maintenance program from the function down.

The high failure rate of RCM amongst mature operations is not surprising when it is realized that RCM was developed by Nolan and Heap (Nolan and Heap, 1978) for use in the design phase of the equipment life cycle (Moubray 1997). It was not designed for use in mature industries as a rationalization tool.

Improvement Tactics

The Dupont Experience - Four Common Strategies

In this predicament, case studies and experience suggest that, outside of cultural and behavioral initiatives, asset managers should be focusing on a few key areas. They must:

• Develop focused maintenance policies,
• Improve planning and scheduling based on the revised policies, and
• Focus on defect elimination.

The Dupont model of Up-Time featured in the Manufacturing Game® illustrates these points very well. The table below illustrates how Dupont has modeled the relative effect of various strategies on plant uptime.

¹A maintenance policy is the combination of what is to be done, how frequently and by whom.

²Particularly if the maintenance is intrusive.

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