Failure declaration standards

A reliability engineer points out that in a mining operation hydraulic leaks in the fleet equipment are a major source of lost production. So during regular inspections the technicians are looking for leaks and if they find them they change the appropriate hose or component. However, it seems  that they should be looking, not for leaks, but for damaged hoses, couplings, or other parts during these inspections, as they would constitute “potential” failures.

This point raises a subject that RCM stresses as one of prime importance. What shall be the “standard” used to declare failure? Different people have different standards and this leads inevitably to the obscuring of company objectives. To the operator, the standard may be a “large leak”. To the technician it may be a “small leak”. To the reliability engineer it may be a “damaged hose – impending leak”. Who decides? Although here it sounds obvious, this is no trivial decision when viewed at the scale of maintenance and production. There are many failure modes to deal with. And they come in all shades of gray and with competing priorities.

Without a systematic “living” RCM knowledge base tightly integrated into the routine work order process, multiple opinions “rule”. The solution is not simple. It requires cross-level on-going dialog in order to get consensus on standards for failure and potential failure. The MESH living RCM software documents that dialog using images to discriminate among Failure, Potential Failure, and Suspension thereby evolving an agreed upon corporate standard. Consistency in failure and suspension declaration will ensure a high quality of data needed for Reliability Analysis and maintenance decision modeling.

© 2011 – 2014, Murray Wiseman. All rights reserved.