Potential Failure Mode is defined as the manner in which machinery could potentially fail to meet its intended function. The potential failure mode may also be the cause of a potential failure mode in a system, subsystem, or component. Machinery failure is an event when machinery is not available to produce parts at specified conditions when scheduled or is not capable of producing parts or performing scheduled operations to specification. For every potential failure, an action is required to bring the machinery back to its intended production capability. Machinery failure modes can occur three ways:
(1) A type of machinery component defect contributing to a failure (hard failures; i.e., bearing seized, shaft broke).
(2) The manner by which machinery system failure is observed or the way the failure occurs (degraded performance; i.e., slow cycle time, excessive process variation).
(3) The abnormality of performance that constitutes the machinery system to be classified as failed (quality defects; i.e., high micro due to vibration, concentricity due to worn shaft bearing diameter).