GE Complete Guide to Outward Bolt Varnish Treatment in 752 Models

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GEK±91584D, Vertical Drilling Motor, Type GE752

Minimum Volts

7.3

Varnish Immersion Treatment After VPI

Maximum Volts

8.5

(Armature)

 

For Magnetic retainers:

 

The following immersion process must be performed

Minimum Volts

0.7

on the armature assembly after the VPI process.

 

Maximum Volts

12.4

1. Preheat the armature in an oven at 140￿ C for at

least five hours.

 

 

High±Potential Test

 

2. The temperature of the armature must not be

 

 

less than 90￿ C, or above 120￿ C, before im-

Frame With Used Coils

 

mersing. Immerse the armature in a vertical po-

 

 

sition (commutator end up) in the varnish (GE

Apply a high±potential test voltage of 2000 volts, 60

Hz for one minute.

Spec. No. A15B53A) for at least one minute.

Frame With All New Coils

Apply a high±potential test voltage of 3500 volts, 60 Hz for one minute.

Measure leakage current to ground during this test.

5.0 milliamps is maximum.

WARNING: Electric shock can cause serious or fatal injury. To avoid such injury, personnel should take and observe proper precautions during the high±potential testing.

Resistance Measurement

Refer to the DATA section for values and measure the resistance of the exciting and commutating fields.

NOTE: One minute is the minimum time to in- sure adequate varnish penetration.

3.Lift the armature out of the varnish and spin until the excess varnish is removed. Clean the shaft with Xylene (GE Spec. No. D5B9).

4.Bake at 140￿ C in an oven for at least eight hours.

BALANCING ARMATURE

Refer to the appropriate longitudinal section (see Table 2, Page 20, to determine the correct drawing) for balance weight locations. Dynamically balance the ar- mature within 10 grams (0.35 oz.) on the drive end and 12 grams (0.42 oz.) on the commutator end by adding weights on the commutator cap and the armature head.

VARNISH TREATMENT (ARMATURE)

Vacuum Pressure Impregnation (VPI)

After all repairs have been completed, the armature must be vacuum pressure impregnated in GE±702C polyester varnish.

Refer to GEK±101183 for VPI procedure.

Following the VPI processing, the armature must be given a varnish immersion treatment.

NOTE: Do NOT clean previously protected ma- chined surfaces, threads and tapped holes be- fore varnish treating the armature.

REASSEMBLY

Brushholders

1.Using a bolt and washer, attach the brushholder clamp to the frame mount. Position the studs of the brushholder in the clamp, and move the brushholder radially outward as far as possible.

2.Tighten the brushholder clamp bolt but do not torque. Install all brushholders.

3.Connect the brushholder cables. Refer to Table 2, Page 20, to determine the correct connection diagram.

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Contents Contents Vertical Drilling Motor Type GE752GEK±91584D, Vertical Drilling Motor, Type GE752 General DescriptionIntroduction Vertical Drilling Motor, Type GE752, GEK±91584D Model DifferencesContd Model Differences DataData Contd Carbon BrushesPole Bore Diameter measured at center of pole Motors Min Max Motor Ratings Continuous Max. HP Shunt UP Special Tools Equipment Grounding InstructionsGrounding Procedures Fig OverhaulLubrication Grease Tubes and Pipe PlugsBrushholders Fig Inspection MonthlyCovers, Seals, Latches Brushholder Sleeves Brush Spring PressureBrushes CommutatorCreepage Band Flash RingSEMI±ANNUALLY Basic Repairs Brush ReplacementBrushholder Replacement Commutator Resurfacing InstallationBrushholder Clearance Adjustment Sanding Procedure Hand Stoning ProcedureGrinder Installation Fixture GrindingCommutator GRINDER. E±18249 Grinding ±19771ABasic Overhaul Testing Before DisassemblyAir Curing Commutator Disassembly Megohmmeter TestBar±To±Bar Resistance Test Armature Removal From FrameCOMMUTATOR±END Bearing Pilot Longitudinal D732922 CHG. N. E±28621D Models See , Description Puller Tools 41D731569 CHG . E±14383C Puller TOOLS. E±18155A Models US1, AUT Longitudinal D735357, CHG. A. E±37949B Models See Table Cleaning Steam CleaningVapor Degreasing Anti±Friction Bearings/Shaft Tapers/Bearing FitsBearing Inspection ArmatureMotor Frame CommutatorArmature Shaft Inspection Armature Insulation 41D731545 CHG. F. E±18156A See Note Brushholders Lubrication of BoltsConnection Diagram 493A210 CHG . E±39092B Creepage Band Replacement Rewinding ArmatureRiser Width DiameterProcedure Commutator TighteningHydraulic Press Preferred Method Torque Wrench Acceptable MethodSpin Seasoning Commutator Assembled On Armature Commutator ResurfacingTurning To Change Motor DirectionConnection Diagram 41A330278, CHG . E±38055B Connection Diagram 41A330179, CHG. A. E±37950A Raking ±4270BResistance Measurement Test After Repair Armature High Potential TestUsed Armature Rewound ArmatureReplacement Coil InstallationProcedure for New Coil±Pole Assembly Motor Frame Field CoilCoiled Frame Assembly 41D732353 CHG. N. E±39094A Models See , Coiled Frame Assembly 41D732345 CHG. V. E±39095A BOX Ground A1 and A2 View AT E Cables with P65 Coiled Frame Assembly 41D735440, CHG. A. E±38056B Description Magnet Frame Coiled Frame Assembly 41D735343, CHG. C. E±37951C Hardened Washer 1 1/4 Brazing Coil Terminals Gas Torch BrazingCoiled Frame Without Armature Flood Dipping Coiled FrameTest After Repair Varnish Treatment Armature ReassemblyBalancing Armature Armature Bearings Drive±End Bearing Figs , 35, 36Commutator±End Bearing All Models Except US2, UP6, AUT2 and AUP5DRIVE±END Bearing ASSEMBLY. E±18166E DRIVE±END Bearing ASSEMBLY. E±39301 Models US2, UP6, AUT2 and AUP5DRIVE±END Bearing Assembly 41B537821, CHG. B. E±37952B Armature Assembly Into Frame Models UP and AUPCOMMUTATOR±END Bearing Assembly 41B532745 CHG. F. E±39090A COMMUTATOR-END Bearing Assembly 41B538068 CHG . E-39300 Checking Internal Clearance Brush Installation Hub Mounting HUB MountingHub Fitting Models 5GE752AUP, AUT Testing After OverhaulTesting Series Machines Testing Shunt Machines Models 5GE752UP and US Motor OperationVentilated 2300 cfm at 7.6 in. H2O at Commutator Chamber UnventilatedCleaning and Slushing Removing Armature Locking ArrangementLocking the Armature For Shipment ShippingSkidding ProtectionArmatures Preparation of BOXBoxing the Armature Storage Placing Into StorageRemoving from Storage Shipping BOX with Armature Less COVER. E±3784Vertical Drilling Motor, Type GE752, GEK±91584D OUTLINE, UP and AUP 41E903631 CHG. H. E±28755B Hole Grease Vent Tube Grease Tube Holes REF OUTLINE, US1, AUT 41E903745, CHG. A. E±37954B ºDº ºBº Vertical Drilling Motor, Type GE752, GEK±91584D GE Transportation Systems