Maintenance Procedure in Industries

After laying down an appropriate policy with a suitable maintenance mix, the maintenance operators can be trained according to the norms set. Usually, the procedure followed by the plant engineers in almost all the industries irrespective of their policy/strategy is as follows.

Step 1: Adjust

Normally, a machine performs out of its specifications due to continuous running. The machine is to be re-adjusted properly in its settings. In some cases this may be termed as calibration also. With simple adjustments, the machine will become all right. To carry out this operation the plant engineer or the maintenance operator should have thorough knowledge on the design of the machine as well as its performance characteristics. It will be an added advantage if plant engineer has got the past data and history of the machine if the machine is old. This job is entrusted to the production department in some industry.

Step 2: Simple Repair

Often the machine can be repaired with a minor repair unless otherwise the machine experiences a fatal accident or subjected to severe wear or mis-operated. In any of the latter cases the fault can be found very easily since it is seen with the naked eye. But in the case of small repairs only, it is very difficult to locate and identify the problem. Once the problem is identified, it shall be very simple to repair. And simple may become complex if not identified in time. The simple repair also includes periodic check up or checking of some parameters at regular or irregular intervals based on hour, miles, output of production or some combination of these and making necessary repairs.

Step 3: In Situ Repair or in Situ Replacement

A machine may fail due failure of a component or part, which is often referred to as in situ replacement or in situ repair in plant engineering terminology. In certain circumstances, it may be considered with Least Replaceable Assembly (LRA) in which the total assembly of the part may be taken out of the machine and replaced with a stand by assembly. The removed assembly may be taken to the plant engineering department and repaired for next use or stand by. This repairing requires sufficient stock of components or spare parts or stands by units, which may most likely to fail that is statistically predictable.

Step 4: Design Out Maintenance

As indicated by cause investigations after major or recurring failure, a thought may be given towards updating the part or component with latest technology and replace the item. A suitable planning and follow up is necessary to do this. A regular watch and statistical analysis with the concept of probability and reliability analyses are the helpful tools for design out maintenance.

However, besides the above procedure, a preventive maintenance programme may be scheduled and adhered to.