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BEFORE TO START ANY DISASSEMBLING YOU MUST MARK ALL DETAOLS VERY CARREFULLY TO AVOID ANY MISTAKE DURING ASSEMBLING

MAINTANANCE OF EL.MOTORS

In the maintenance of electric motors, there comes a time when further operation is impossible without repair.

PROCEDURE OF DISASSEMBLY OF EL.MOTORS

Disassembly of the motor should be conducted so as not to damage the individual parts. Therefore, when disassembling is not allowed to use excessive force, sharp blows.

Before disconnect el.motor you must mark the phases in any convenient manner, the main thing that when you return to the starting position, you're not guessing and confidently hooked as it was.

INSULATION RESISTANCE TEST TO GROUND SHALL BE PERFORMED BEFORE STARTING OF OVERHAULING AND AFTER.

BEFORE TO START ANY DISASSEMBLING YOU MUST MARK ALL DETAOLS VERY CARREFULLY TO AVOID ANY MISTAKE DURING ASSEMBLING

FUNDAMENTALLY A THREE-PHASE INDUCTION MOTOR CONSISTS OF TWO PARTS: STATOR AND ROTOR.

1. Frame; 2.Laminated magnetic core; 3.Laminated magnetic core; 4 Endshields; 5. Fan; 6. Fan cover; 7. Shaft; 8. Three-phase windings; 9. Therminal box; 10.Therminals; 11. Bearings; 12.Rotor.

In the horizontal position (or convenient position) first remove any accessory items (fans, blower, feedback devices, etc.)

Remove the pulley or coupling by corresponding size of puller (see photo). Thus it is necessary to make sure that the direction of efforts to coincide with the axis of the shaft, otherwise possible misalignment, which causes damage to the shaft of el.motor or fan.

To avoid of damage the coupling should be heated for easily remove.

 



Begin to remove the covers bolted, there may be 3, 4, 5, and even more.

Eversible bolts tight moistened with WD-40 or analog spray and left for a time, after which the bolts weaken and twisting. When the bolts removed, gently tap hammer throws a pad the cover; one tapped the sides and the other holding a tightness that did not go back on impact. Do it carefully, there are times when break off "ears" on the cover, and this is a headache. Parts storage bolts and small parts shall be stored in dedicated containers and parts from other jobs shall not be mix with them.

 



 



When the covers are removed, determine: whether to pull the rotor out or make further repairs on the spot.

 



Typically, electric motors up to 17 kW the rotor can be pulled out; more than 17kW, can be produced on-site work. When disassembling small motors the rotor removed manually. If a large rotor of el.motor need be pulled out, then it is necessary for this purpose on the rotor shaft on both sides wear suitable pipe again and gently remove the rotor from the stator windings are not touching the winding, supporting his weight all the time.

 



Replaceable bearings removed from the shaft, using special size of puller.

 



 



 



 



 



Washed with Electroclean bearing covers, shaft, nipples, seals, etc

Winding and cooling ducts shall be cleaned, dried and inspected.

 



 



 



 



Dirt accumulations around coil wiring insulation are the biggest cause of motor failure. There are cases that have to wash all the winding due to heavy pollution grease (see photos below)

Cleaning the components, including the stator windings, shall be cleaned with Electroclean with compressed air after heavy deposits of dirt and grease have been removed by scraping and wiping.

 



 



Then the stator and rotor must be thoroughly dried, making sure that windings are dry.

The winding shall then be coated by using a Class F or higher grade varnish in spray. The time for drying varnish shall be sufficient to penetrate any cracks and give a sealed durable finish to the insulation.

 



 



 



PROCEDURE OF ASSEMBLY OF EL.MOTORS


Date: 2016-01-03; view: 1800


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