As years in service increase, all machines are subject to abrasion and damage which lead to breakdowns and deterioration that occur as a result of changes in surface color and appearance, corrosion, stains as well as accidental failures.
(b) Repair
When a machine can no longer be used due to a breakdown:
* discard................replace with a new machine
* repair and reintroduce .... repair the deteriorated components and reintroduce the
into service machine into service.
(2) Functional maintenance
"Functional Maintenance" refers to the process of repairing the parts of a machine that deteriorate during the normal course of operations and maintaining all functional parts at their normal rated efficiency to ensure that operations can always be performed properly.
The methods available for maintaining machine functions are:
* Preventive Maintenance .... maintenance operations performed before a component has reached the point of being unable to support the demands placed on it during normal operations.
* Corrective Maintenance .... maintenance operations performed after a component has reached the point of being unable to support the demands placed on it during normal operations.
The need for effective preventive maintenance can be expressed as follows.
(a) Safety
Ensuring safety of operations is the single greatest responsibility of a transportation organization. It is imperative that a strategy be designed to prevent accidents before they occur. Preventive maintenance is therefore required to ensure that safe and reliable transportation services are available.
(b) Economic viability
Table 1-1 is a comparison of the relative costs involved in preventive maintenance and corrective maintenance.
