Overall Equipment Effectiveness (OEE) is an important equipment performance measure. It is the mathematical product of availability, performance and quality.
To improve OEE, all the 3 components must be improved.
First, let us look at some general maintenance management principles, that when applied, give an immediate result in equipment and maintenance efficiency.
Once implemented, these principles give a good insight to the maintenance workload, make it easier to plan the work orders, and improve the communication between the maintenance and production departments.
These are the principles:
- A work orders have to be made for emergency repair work, planned jobs and preventive maintenance jobs
- For planned jobs, priorities have to be defined
- Work orders have to be prepared (materials, number of hours, crafts and tools)
- When the number of hours are known per work order, the workload becomes visible
- When priorities are defined, it is easier to plan and optimise the resources.
- When work orders are executed, the real hours and comments have to be entered, so that the history of executed work orders becomes a working instrument.
- An easy system must be in place to manage the above principles.
These principles are simple and easy to execute. There is no need to wait for highly priced or sophisticated computer programmes to monitor the work. Simple word processor documents or spreadsheets can be used to make good formats and records. At this point, these records may not allow deep analysis of failure patterns, expenditure on each job etc.
As the maintenance crew gains experience and confidence in the operations, upgrade and start using good CMMS / EAM systems that would give more flexibility to maintenance planning. There would be improvement in both efficiency and effectiveness of maintenance. On the long run, there will be cost reductions by way of better labour productivity, reduced inventory costs, enhanced equipment life, increased system reliability and optimised maintenance effort. Finally, the OEE also will improve since mathematical values of all the three components would be higher.