Evaluation of Maintenance Performance
The performance of maintenance department can be assessed in many ways since it is connected to many factors. In fact, it becomes very difficult at times and may raise conflicts also. Of course, the terms like MTTF, MTTR, MTBF, and MDT etc are the most common methods to evaluate the performance of the maintenance and the efficiency of its personnel. Some people do not accept or do not get satisfied with these analyses. They claim that they did the best and throw the blame the equipment inefficiency or its operators' faults. Though acceptable in some cases the blames of the production and maintenance departments on each other can be answered by the following ratios or indices. These are often referred to as Maintenance Performance Indices or Maintenance Performance Indicators (MPI). These can also be used to decide the incentives for the maintenance workmen.
- Effectiveness of Maintenance Planning
= Downtime due to scheduled maintenance/ Downtime due to total maintenance work
= Number of breakdowns/ Available machine hour
- Equipment Utilisation Factor
= (Equipment operating time/ Total available time)
Or
Equipment Capacity Utilisation
= (Equipment operating time/ Total available time) × 100
= Operation time/ (Operation time + Maintenance time)
Percent availability = (Total available hours - Down time)/ Total available hours × 100
= Total maintenance costs/ Total annual sales
- Overhaul Expenditure Ratio
= Overhaul expenditure/ Value of equipment
= Value of spares consumed/ Value of equipment
= Cost of total breakdown repair/ Total number of breakdowns
- Maintenance Man Power Efficiency
= Actual total man hours spent on maintenance job/ Total planned man hours for maintenance work
- Maintenance over Time Ratio
= Over time hours used for maintenance/ Total maintenance hours