Vertical Drilling Motor, Type GE752, GEK±91584D

 

MOTOR FRAME FIELD COIL

Remove the pole bolts and the coil±pole assem-

REPLACEMENT

bly from the magnet frame.

Refer to Table 2, Page 20, to determine the correct

3. Mark any shims for reassembly with the corre-

sponding pole when the coil(s) is installed in the

coiled frame assembly drawing for the machine being

frame.

repaired.

Coil Installation

Coil Removal

 

 

 

Procedure for New Coil±Pole Assembly

1.Remove terminal insulation and disconnect coil leads. Use a gas torch or brazing tongs to sepa- rate brazed connections. When using brazing tongs use low voltage and high a±c current to heat coil connections.

WARNING: Safety glasses and leather gloves must be worn at all times during brazing oper- ations to protect personnel from physical harm.

NOTE: If a gas torch is used, coil insulation must be protected from heat by a non±flam- mable heat absorbent.

1.Pack absorbent around the insulation near the connection and over adjacent coils.

2.Make sure all exposed insulation is covered with a thick layer of absorbent, then heat and separate the coil connections.

2.Heat the coiled frame in an oven at 150￿ C (302￿

F)for four hours to soften the varnish so pole bolts can be removed.

NOTE: Install any exciting coils and braze their connections before installing commutating coils.

1.Before installing any coil and pole, clean the pole contact surface on the frame and the pole piece mounting surface.

2.Install the new pole and coil in the frame with any shims that were on the damaged coil. Use new washers under bolt heads. Lubricate the bolt heads, threads and washers and draw the pole bolts moderately tight.

3.Refer to Table 2, Page 20, to determine the cor- rect coiled frame assembly drawings. All coil connections must be brazed with silver solder, GE±B20A6. Use two pieces of solder (0.010 x 1 in. x 1 in.) between terminal surfaces and braze terminals as follows:

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GE GE752 manual Motor Frame Field Coil, Replacement, Coil Installation, Coil Removal, Procedure for New Coil±Pole Assembly