New research and techniques of World Maintenance

New research

Quite apart from greater expectations, new research is changing many of our most basic beliefs about age and failure. In particular, it is apparent that there is less and less connection between the operating age of most assets and how likely they are to fail.

Figure 1.2 shows how the earliest view of failure was simply that as things got older, they were more likely to fail. A growing awareness of 'infant mortality' led to widespread Second Generation belief in the "bathtub" curve.

However, Third Generation research has revealed that not one or two but six failure patterns actually occur in practice. This is discussed in detail later, but it too is having a profound effect on maintenance.

New techniques

There has been explosive growth in new maintenance concepts and techniques. Hundreds have been developed over the past fifteen years, and more are emerging every week.

Figure 1.3 shows how the classical emphasis on overhauls and administrative systems has grown to include many new developments in a number of different fields.

The new developments include:

decision support tools, such as hazard studies, failure modes and effects analyses and expert systems
new maintenance techniques, such as condition monitoring
designing equipment with a much greater emphasis on reliability and maintainability
a major shift in organizational thinking towards participation, team-working and flexibility.

A major challenge facing maintenance people nowadays is not only to learn what these techniques are, but to decide which are worthwhile and which are not in their own organizations. If we make the right choices, it is possible to improve asset performance and at the same time contain and even reduce the cost of maintenance. If we make the wrong choices, new problems are created while existing problems only get worse.

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