Assessment of Maintenance Effectiveness for Repairable Systems: PM and CM Case Studies

Corrective maintenance (CM) is carried out on a repairable system on failure while preventive maintenance (PM) is done at scheduled time. Very little work is reported in the literature on estimation of parameters with PM and CM models. A good estimation of these parameters is required to assess system condition and the effect of maintenance on the system. Given time-between-failure data and maintenance times data, it is possible to estimate the PM & CM maintenance effectiveness. This paper reviews some PM and CM models, estimates the parameters in those models, and then uses cases to study the effectiveness of maintenance using these models.