RCM Systems - Overview

In reliability analysis Systems contain a set of interrelated or interacting equipment and are used to perform ‘Failure Mode and Effect Analyses’. By dividing a unit into logical Systems, groups of equipment can be identified that may cause similar functional failures. In this approach the reliability analysis of the equipment can be done more clear and effective. Note that under a unit at least one System is needed to perform RCM analyses in IMS RCM.

Dividing a process-unit into one or more Systems may ask for process knowledge which can typically be found in Process descriptions, in Operations training material and from input of a plant process technologists or process engineer.

In IMS-RCM a System is an object that is defined under a unit and is attributed with a definition of the ‘Function of the System’ and the System’s ‘Functional Failures’. Equipment can be assigned to a System for which the Failure mode(s) can cause a Functional Failure of the System. For further clarification you can review the Terms of Reference for IMS-RCM study of HDS unit, where the example HDS unit was split into the following three Systems:In this case, the three Systems are dependent of each other, so downtime of one system will cause downtime of the whole unit – resulting into one PLE value being applicable for all these three Systems.