Specifications

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changing every 5000kM), This type of maintenance allows us to use the parts/equipment to the
limit of their service life. Compared to periodic maintenance, predictive maintenance is condition
based maintenance. Basically, predictive maintenance differs from preventive maintenance by
basing maintenance need on the actual condition of the machine rather than on some preset
schedule. It is possible to schedule maintenance activities to minimize or delete overtime cost.
Also, inventory and order parts can be minimized as required, well ahead of time to support the
downstream maintenance needs. It helps to optimize the operation of the equipment, saving
energy cost and increasing plant reliability.
Corrective maintenance : It improves equipment and its components so that preventive
maintenance can be carried out reliably. Equipment with design weakness must be redesigned
to improve reliability or improving maintainability
Maintenance prevention : It indicates the design of a new equipment. Weakness of current
machines are sufficiently studied (on site information leading to failure prevention, easier
maintenance and prevents of defects, safety and ease of manufacturing) and are incorporated
before commissioning a new equipment.
15.3 Preventive maintenance schedule
Preventive maintenance is the maintenance which has to be carried out to the equipment,
in a preplanned way before serious breakdown takes place. If a record is maintained for certain
measurable parameters like body and bearing temperature, insulation resistance, earth resistance
etc., it is possible from the scrutiny of this record to predict the occurrence of future trouble and
necessary steps can be taken to prevent the occurrence of serious breakdown.
The interval of doing various maintenance operations, depend upon the type of equipment,
ambient condition and other factors. It is difficult to laydown hard and fast rules covering all
conditions but for average normal industrial duty under-mentioned time schedule will serve as
guide. This can be modified to suit other conditions at site.
Daily maintenance : 1) Examine visually earth connections and motor leads. 2) Check motor
windings for overheating. 3) Examine control equipment. 4) Check condition of bearings.
6) Add oil, if necessary, 7) Check end play.
Weekly maintenance : 1) Check belt tension. In the case of sleeve bearing machines the air
gap between-rotor and stator should be checked. 2)Blow out dirt from the windings of protected
type motors situated in dusty locations. 3) Examine starting equipment for burnt contacts where
motor is started and stopped frequently. 4) Examine oil in the case of oil ring lubricated bearings
for contamination by dust, grit etc. (this can be roughly judged from the colour of the oil).
5) Check the intensity of vibrations during operation of the motor. 6) Clean filters where provided.
Monthly maintenance : 1) Overhaul controllers. 2) Inspect and clean oil circuit breakers.
3) Renew oil in high speed bearings in damp and dusty locations. 4) Wipe brush holders and
check bedding of brushes of slip-ring motors. 5) Check that the connections of temperature
detectors and space heaters, where provided, are proper and these are in working order.