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Joliet Equipment Corporation
Engineered Drilling Motors
Maintenance &Spare Parts Manual
Models: JEC75YZB, JEC75YZE, JEC75ZB,JEC75ZE, JEC75ZB-F, JEC75ZE-F
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General Product Information
Parts List/Diagram 6-7
Models 8
Differences Between Models 9
General Specications 10-12
General Operation Information 13
GeneralFeatures 13
ATEXCerticationSafetyConsiderations 13
SafeElectricalParametersShuntWound 14
SafeElectricalParametersSeriesWound 14
Warnings 14-15
ClosedCoolingSystems 15
SpecialHandlingRequirements 15
Grounding 15-16 Lubrication 16
SpecialTools 16
Inspections 17
MonthlyInspections 17-19
InspectionpriortoOperation 20
InspectionsforClosedCoolingSystems 20
Semi-AnnualInspections 20
Motor Overhaul 21
TestingtheMotorbeforeDisassembly 21
DisassemblingtheMotor 21
RemovingtheHub 21-22
RemovingtheArmatureFromtheFrame 22-23
TestingafterOverhaul 23
TestingSeriesModels 23
TestingShuntModels 24
Cleaning 25
SteamCleaning 25
VaporDegreasing 25
CleaningAnti-FrictionBearings/ShaftTapers/BearingFits 25
Contents
Contents:Part1
Rev. 07152010
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Working with the Motor Parts
The Brush and Brushholder
ReplacingtheBrushes 26
RemovingtheBrushes 26
InstallingtheBrushes 26
ReplacingtheBrushholders 26
InstallingtheBrushholders 27
AdjustingtheBrushholderClearance 27
InspectingandTestingtheBrushholders 27
ReplacingtheBrushholderSleeves 27
ReassemblingBrushholders 28
The Armature 28
InspectingandTestingtheArmature 28
ReplacingtheArmatureCreepageBand 28 AssemblingtheArmatureintotheFrame
(ModelsYZE,YZK,ZE-F,ZK-F,ZE,ZK) 28-30
AssemblingtheArmatureintotheFrame
(ModelsYZB,YZH,ZB-F,ZH-F,ZB,ZH) 30-31
RemovingtheArmatureLockingArrangement 31
LockingtheArmatureforShipment 31
TestingtheArmatureafterRepair 31
ArmatureVarnishTreatment 32
BalancingtheArmature 32
Inspections 32
InspectingtheInsulation 32
InspectingtheCommutator 32
InspectingtheArmatureShaftBearingFits 32
InspectingtheCreepageBand 32
Resurfacing the Commutator 33
Grinding 33
Turning 33
Undercutting 33
Raking 34 Polishing 34
The Motor Frame 35
Inspecting and Testing the Motor Frame 35
ReplacingtheMotorFrameFieldCoil 35
RemovingtheCoil 35
InstallingtheCoil 36
Contents
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The Motor Frame (continued)
Brazing the Coil Terminals 36
UsingtheMachineBrazingMethod 36
UsingtheGasTorchBrazingMethod 36
FloodDippingtheCoiledFrame 37
Testing the Coiled Frame 37
TestingafterRepair(withoutArmature) 37
TestingafterRepair 37
The Connection Boxes 38
ChangingthePositionoftheConnectionBox 38-39
InsulatingtheTerminalConnections 39
AssemblingtheConnectionBox 39- 40
DifferencesforShuntMotors 40
The Commutator 41 ResurfaceBasedonCondition 41
SafetyRequirements41
PreparingtheCommutatorforResurfacing 41
PreparingforResurfacingforSeriesMotors 41
PreparingforResurfacingforShuntMotors 42
SandingtheCommutator 42
HandStoningtheCommutator 42-43
FixtureGrinding 43
InstallingtheGrinder 43
GrindingtheCommutator 43-44
AirCuringtheCommutator 45
The Bearings 46
InspectingtheBearings 46
ReassemblingtheBearings 46
ReassemblingtheArmatureBearings 46
ReassemblingtheDrive-EndBearing46-47
ReassemblingtheCommutator-EndBearing(ShuntWoundMachines) 47
ReassemblingtheCommutator-EndBearing(SeriesWoundMachines) 47
The Hubs 48 HubFitting 48
MountingtheHub 48- 49
The Bolts50
LubricatingtheBolts50
StandardBoltTorqueValues 51
Index 52-54
Contents
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JOLIETEquipmentCorporationcontinuouslyinvests
inglobalmanufacturingalliancestobringthebestin
electricmotorsandrelatedtechnologytoAmerica.
OneofNorthAmericasleadingsuppliersoflarge,
heavy-dutyelectricmotors,JOLIETEquipment
Corporationhasbeenbuildingandrebuildingelectric
motorsformorethan75yearswithbettervalueand
unequaledqualityandsupport.JOLIETEquipment
Corporationmeanspowerinsteelmills,papermills,
petrochemicaloperationsandhigh-performance,
deep-drillingoffshoreequipmentsettingheavy-duty
operatingstandardsfromtheAmericastothePacic
Rimandcustomersitesaroundtheworld.
Formorethantwogenerations,JOLIETEquipment
Corporationhasbeensettingqualitystandardsand
specicationsforelectricmotors.Carefullychosen
alliancesandqualitycontrolmeasuresinsurethat
JOLIETEquipmentCorporationcustomerswillreceive
theabsolutebestinelectricmotorperformanceand
value.
General Product Information
Joliet Equipment Corporation Bringing You the Best in Electric Motors
Reconditioned DC Drilling Motors
JEC75ZB JEC75ZEJEC75YZF(Top Drive)
JEC75ZB-F JEC75ZE-F
Type: (Series/Shunt) Series Shunt Series/Shunt Series Shunt
HP: (Continuous) 1000 1000 1085/1130 1085 1130
HP: (Intermittent) 1250 1250 1320/1365 1320 1365
Voltage: (VAC) 750 750 750 750 750
Full Load Current: (Continuous) 1050 1050 1150/1185 1150 1185
Full Load Current: (Intermittent) 1400/1435 1400 1435
Full Load RPM: 965 1040 965/1040 965 1040
Horizontal / Vertical: Horizontal Horizontal Vertical Horizontal Horizontal
Torque: (@ Base RPM): (Continuous) 5200 5050 5900/5705 5900 5705
Torque: (@ Base RPM): (Intermittent) 6800 6300 7530/6745 7530 6745
Available Certication: ABS ABS ABSATEX ABS ABS
Approx. Weight: (lbs.) 6900 6900 7150 7150 7150
Add1aftermodelnumberforMarineDutyAdd3aftermodelnumberforLandDuty
New DC Drilling Motors
JEC75YZB JEC75YZEJEC75ZF
(Top Drive)
Type: (Series/Shunt) Series Shunt Series/Shunt
HP: (Continuous) 1085 1130 1085/1130
HP: (Intermittent) 1320 1365 1320/1365
Voltage: (VAC) 750 750 750
Full Load Current: (Continuous) 1150 1185 1150/1185
Full Load Current: (Intermittent) 1400 1435 1400/1435
Full Load RPM: 965 1040 965/1040
Horizontal / Vertical: Horizontal Horizontal Vertical
Torque: (@ Base RPM): (Continuous) 5900 5705 5900/5705
Torque: (@ Base RPM): (Intermittent) 7530 6745 7530/6745
Available Certication: ABSATEX ABSATEX ABSATEX
Approx. Weight: (lbs.) 7150 7150 7150
Add1aftermodelnumberforMarineDutyAdd3aftermodelnumberforLandDuty
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DESCRIPTION PART NUMBER
1 Outer Seal 10-53 D0011
2 Drive-End Outer Bearing Cap 10-53-D0012
3 Drive-End Bearing Cap Bolts 10-53-D0013
4 Bearing Cap Lock Washers 10-53-D0014
5 Drive-End Outer Gasket 10-53-D0015
6 Drive-End Bearing 10-53-D0016
7 Hi-Torque Endbell 10-53-D0017
8 Bolts & Washers 10-53-D0018
9 Drive-End Bearing Spacer/Slinger 10-53-D0019
10 Drive-End Inner Bearing Cap 10-53-D0020
11 Inner Seal 10-53-D0021
12 Cable S2 10-53-L0022
13 Cable S1 10-53-L0023
14 Cable A2 10-53-L0024
15 Cable A1 10-53-L0025
16 Frame/Lead Grommet 10-53-L0026
17 Blower Seal Tite 10-53-L0027
18 Seal Tite 10-53-L0028
19 Seal Tite 10-53-L0029
20 Armature with Shaft 10-53-A0030
21 Exhaust Cover B 10-53-F0031
22 Exhaust Cover C 10-53-F0032
23 Exhaust Cover A 10-53-F0033
24 Exhaust Cover D 10-53-F0034
25 Inner-pole Bolt 10-53-F0025
26 Inner-pole Pole Piece 10-53-F0036
27 Inner-pole Coil 10-53-W0037
28 Inner-pole Shims 10-53-F0038
29 Inner-pole Shims 10-53-F0039
30 Commutator Covers - Upper 10-53-F0040
31 Field Coil Bolt 10-53-F0041
32 Field Coil Bolt Washer 10-53-F0042
33 Field Coil Open 10-53-W0043
34 Field Coil Crossed 10-53-W0044
35 Field Coil Spring Plate 10-53-F0045
36 Field Coil Pole Piece 10-53-F0046
37 Frame 10-53-F0047
38 Blower Mount Bolt 10-53-B0048
39 Blower Mount Washer 10-53-B0049
40 Blower Assembly 10-53-B0050
41 Commutator-End Bearing Cap Bolts 10-53-C0051
DESCRIPTION PART NUMBER
42 Commutator-End Outer Bearing Cap 10-53-C0052
43 Commutator-End Bolts & Washers 10-53-C0053
44 Gaskets 10-53-C0054
45 Commutator-End Endbell 10-53-C0055
46 Commutator-End Bearing Lock NutSet Screw
10-53-C0056
47 Commutator-End Bearing Lock Nut 10-53-C0057
48 Commutator-End Bearing / Outer Ring 10-53-C0058
49 Commutator-End Bearing 10-53-C0059
50 Commutator-End Inner Bearing Cap 10-53-C0060
51 Brush Holder Assembly 10-53-C0061
52 Carbon Brush 10-53-C0062
53 Washer 10-53-F0063
54 Bolt 10-53-F0064
55 Bottom Bolt-on Cover 10-53-F0065
56 Bottom Spring Cover 10-53-F0066
57 Copper Bus Connection 10-53-T0067
58 Terminal Box Covers 10-53-T0068
59 Bolt 10-53-T0069
60 Washer 10-53-T0070
61 Bolt 10-53-T0071
62 Washer 10-53-T0072
63 Washer 10-53-T0073
64 Glastic Stand Off 10-53-T0074
65 Bolt 10-53-T0075
66 Connection Plate 10-53-T0076
67 Gland 10-53-T0077
68 Terminal Box 10-53-T0078
69 Crouse-Hinds Lockout Switch 10-53-T0079
70 Pressure Switch (XP) 10-53-T0080
71 Space Heater (120/240 VAC) 10-53-T0081
72 Terminal Board w/Indicator 10-53-T0082
73 Oileld Hub 10-53-S0083
74 Hi-Torque Endbell 10-53-D0084
75 Exhaust Cover Gasket 10-53-F0085
76 Nomex Gasket 10-53-F0086
77 Nomex Gasket 10-53-F0087
78 Blower Gasket 10-53-B0088
79 Blower Filter 10-53-B0089
PartsList/Diagram
Parts List/Diagram
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Model Series Wound (H) Shunt Wound (K)
C75ZB(E)
Reconditioned 1000HP DC Drilling
Continuous rating for mud pump and
rotary table applications of 1000 HP
Intermittent rating for drawworks
applications of 1250 HP
Continuous rating is at 750 VDC,
1050 Amperes, 965 RPM
Continuous rating for mud pump and
rotary table applications of 1000 HP
Intermittent rating for drawworks
applications of 1250 HP
Continuous rating is at 750 VDC, 57
Amps, 1050 Amperes, 1040 RPM
C75ZB(E)-FReconditioned DC Hi-Torque Drilling Motor
Continuous rating for mud pump and
rotary table applications of 1085 HP
Intermittent rating for drawworks
applications of 1320 HP
Continuous rating is at 750 VDC,1150 Amperes, 965 RPM
Continuous rating for mud pump and
rotary table applications of 1130 HP
Intermittent rating for drawworks
applications of 1365 HP
Continuous rating is at 750 VDC,60 Amps, 1185 Amperes, 1040 RPM
Models
C75YZB(E)New DC Hi-Torque DC Drilling Motor
Continuous rating for mud pump and
rotary table applications of 1085 HP
Intermittent rating for drawworks
applications of 1320 HP
Continuous rating is at 750 VDC, 1150Amperes, 965 RPM
Continuous rating for mud pump and
rotary table applications of 1130 HP
Intermittent rating for drawworks
applications of 1365 HP
Continuous rating is at 750 VDC,60 Amps, 1185 Amperes, 1040 RPM
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Differences Between Models
ThefollowingtableliststhedifferencesbetweenthevariousmodelsofJOLIETEquipmentCorporationmotors.
Model Differences
C75ZB / H
Reconditioned 1000HP DC Drilling
C75ZB Horizontal Series; left-hand terminal box
C75ZH Horizontal Series; right-hand terminal box
C75ZE / KReconditioned 1000HP DC Drilling
C75ZE Horizontal Shunt; left-hand terminal box
C75ZK Horizontal Shunt; right-hand terminal box
C75ZB-F / HReconditioned DC Hi-Torque Drilling Motor
C75ZB-F Horizontal Series; left-hand terminal box
C75ZH-F Horizontal Series; right-hand terminal box
C75ZE / K-FReconditioned DC Hi-Torque Drilling Motor
C75ZE-F Horizontal Shunt; left-hand terminal box
C75ZK-F Horizontal Shunt; right-hand terminal box
C75YZB / HNew DC Hi-Torque DC Drilling Motor
C75YZB Horizontal Series; left-hand terminal boxC75YZH Horizontal Series; right-hand terminal box
C75YZE / K
New DC Hi-Torque DC Drilling Motor
C75YZE Horizontal Shunt; left-hand terminal box
C75YZK Horizontal Shunt; right-hand terminal box
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General Specications
Locationofmainconnectionboxes(lookingatcommutator-end)
Connectionboxonleftside,modeldesignationswithsufxletterB and E.
Connectionboxonrightside,modeldesignationswithsufxletterH and K.
Motor Part / Motor Characteristic Specication Data
Max. Permissible Speed Motors 2300 RPM
Max. Permissible Vibration (Commutator End) 0.002 in.
Resistance at 25C (ohms) Min. Max.
Armatures
Models: C75ZE(K), C75ZE(K)-F, C75YZE(K) 0.00749 0.00800
Models: C75ZB(H), C75ZB(H)-F, C75YZB(H) 0.00749 0.00800
Exciting Fields
Models: C75ZE(K), C75ZE(K)-F, C75YZ(K) (With Cables) 1.13 1.22Models: C75ZB(H), C75ZB(H)-F, C75YZB(H) (With Cables) 0.00513 0.00549
Commutating Fields
Models: C75ZE(K), C75ZE(K)-F, C75YZE(K) (With Cables) 0.00431 0.00492
Models: C75ZB(H), C75ZB(H)-F, C75YZB(H) (With Cables) 0.00431 0.00492
Carbon Brushes
Type T900
Size 3/4 x 2-1/4 x 2 in.
Minimum Brush Length (length at which brush becomes
inoperative measure brush on the longest side)
1-3/32 in.
Spring Pressure on Brush, Preset 10-12 lb.Brushholder
Clearance to Commutator 1/16-3/32 in.
Clamp Bolt Torque 225-250 lbs-ft
Commutator
Side Mica Thickness 0.060 in.
Slot Depth 0.047 in.
Undercutting Saw
Width 0.063 in.
Diameter 1.000 in.
Commutator DiameterNew 16.625 in.
Worn (minimum permissible) 15.375 in.
Riser Width (minimum permissible) 0.625 in.
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Motor Part / Motor Characteristic Specication Data
Lubrication Armature Bearings
Grease Capacities
Drive-end 32.5 oz.
Commutator-end
Models YZE/K, YZB/H, ZE/K-F, ZB/H-F, ZE/K, ZB/H 12.25 oz.
Model YZF, ZF-F, ZC, ZF 31.8 oz.
Lubricant Shell Cyprina RA
Weights (approximate)
Complete 6720 lb.
Armature Only 2100 lb.
High-Potential Test 60 Hz, a-c, to ground for one minute (All Windings) (Volts)
New or Rewound Armature 3500 V
Reconditioned 2000 V
Minimum Megohmmeter Reading (ohms) 2 megohms
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General Operation Information
p
JOLIETdrillingmotorsareusedtopoweroffshore
andland-baseddrillrigsusedbytheoilandgas
industry.Forthespecicratingsforeachmotor,see
Models.
General Features
Inprovidingthebestelectricmotorsandrelated
technology,JOLIETdrillingmotorsinclude:
Alargearmatureslotcongurationprovidinga
heavycoppercrosssectiontoincreasethemotors
capabilityforcarryinghighcurrentloads.
Aspiralgroovecommutatorwhichhelpscoolthe
commutator(high-torquemodels).
Highcurrentexcitingandcommutatingpoleeld
coils.
Improvedinternalairowforincreasedcooling.
Anopenpinion-endframeheadforincreased
cooling(high-torquemodels).
Theabilitytooperatethedrillingmotorineither
rotationaldirection.
Theabilitytomountthepressurizedcontrolbox
oneithersideofthemotor.Formoreinformation,
seeChanging the Position of the Connection Box.
ATEX Certication SafetyConsiderations
Thefollowinglistprovidesthespecialconditionsyou
shouldfollowforsafeuseofanyJOLIETdrillingmotor:
1. Youmustfollowthesepressurizationand
purgingrequirements:
a. Aminimumairowof3000ft.3/min.
(85m3/min.).
b. Aminimumpurgetimeof5minutesplus10
secondsforeveryadditional35.3ft.3(1m3)
ofducting.
c. Aminimumlowpressuresettingof2in.of
WG(5mbar).
2. Itisyourresponsibilitytoensurethatany
certiedancillariesusedinconjunctionwiththe
motormeettheconditionsfortheiruse.
3. Youhaveconnectedthewindingresistance
temperaturedetectors(RTDs)eitherintointrinsi-
callysafecircuits,oryouhavetheminterlocked
withthepurgingsystemsothattheycannotbe
energizeduntilthemotorhascompletedapurge
cycle.
4. TheSpecialConditionsforsafeuseorthe ScheduleofLimitationsasappropriatefor
Certicates.
5. Whenyouactivatetheauxiliaryswitch,thatis
youhavepinnedthemotors,ACvoltagemay
stillbepresentonthedeviceterminalboards.
Thespaceheater(240VAC)andblowerunit
(460or575VAC)maystillbeonunlessyou
havepreviouslyswitchedthemoff.Thereisa
dangerofasevereelectricalshockifyoudo
notswitchoffthespaceheaterandblowerunit
whenyouactivatetheauxiliaryswitch.
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Safe Electrical Parameters Shunt Wound
Thefollowingtableliststhesafeelectricalparameters
forshuntwoundJOLIETdrillingmotors.
Category Rating
Shaft horsepower 1130
Armature Volts DC 750
Armature Amps DC RMS 1185
Shunt eld Amps 60
Full Load RPM 1040
Maximum RPM 2300
Maximum ambient temperature 40C
Internal free volume (cu. ft.) 6.6
Minimum purge / cooling ow
rate
3000 CPM
Minimum purge time 5 min (plus 10 seconds for
each cubic meter of duct)
Minimum overpressure at
enclosure
2.00 in. WG
Minimum differential pressure
through frame
6.00 in. WG
Incoming cable maximum
operating temperature
125C
Safe Electrical Parameters Series Wound
Thefollowingtableliststhesafeelectricalparameters
forserieswoundJOLIETdrillingmotors.
Category Rating
Shaft horsepower 1085
Armature Volts DC 750
Armature Amps DC RMS 1150
Full Load RPM 965
Maximum RPM 2300
Maximum ambient temperature 40C
Internal free volume (cu. ft .) 6.6
Minimum purge / cooling ow
rate
3000 CPM
Minimum purge time 5 min (plus 10 seconds for
each cubic meter of duct)
Minimum overpressure at
enclosure
2.00 in. WG
Minimum differential pressure
through frame
6.00 in. WG
Incoming cable maximum
operating temperature
125C
Warnings
Toensureyoursafety,followthefollowingwarnings
whenworkingonJOLIETdrillingmotors:
1. Poorlygroundedequipmentcanbeashock
hazard.Youmustgroundtheequipmentbefore
use.Thereisapotentialforseriousorfatalinjury
fromelectricalshockifyoudonotproperly
groundelectricalequipment.
2. Usingcompressedairforcleaningpurposescanraisedebrisandyingparticles.Compressedair
mayalsocontainmoisture;donotuseon
energizedmotor.Wearsafetyglassesandother
personalprotectiveequipmentwhenusing
compressedairforcleaningpurposes.Flying
debrisandparticlesmayalsopresentahazard
topersonnelintheimmediatearea.Improper
protectioncanresultinseriousinjury.
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3. Removingorreplacingbrusheswhilethe
equipmentisenergizedorrotatingcanbe
ashockhazard.Donotremoveorreplace
brusheswhiletheequipmentisenergizedor
rotating.Electricshockcancauseseriousor
fatalinjury.
4. Testingcanbeashockhazard.Electricshock
cancauseseriousorfatalinjury.Takeproper
precautionsduringtesting.
5. Resurfacingoperationscanraisedustand
yingparticles.Wearsafetyglassesanda
respiratorforprotectionfromdustandying
particlesduringresurfacingoperations.Improper
protectioncanresultinseriousinjury.
6. Highpotentialtestingcanbeashockhazard. Electricshockcancauseseriousorfatalinjury.
Takeproperprecautionsduringhighpotential
testing.
7. Brazingrequiresextremelyhightemperatures.
Wearsafetyglassesandleatherglovesatall
timesduringbrazingoperations.Improper
protectioncanresultinseriousinjury.
8. UsingMEKasacleaningsolutioncanbea
healthhazard.Donotinhalethefumes.Use
MEKonlyinawell-ventilatedarea.Take
adequateprecautionstoprotectyoureyes,
skinandhands.Improperprecautionscan
resultininjur y.
Youwillseethesewarningsthroughouttheservice
catalogasareminderoftheseconditions.
Closed Cooling Systems
YoucanmountJOLIETdrillingmotorsinatotally
closedcoolingsystemwithanairtowaterheatex-changer.Ifyouusethisalternatecoolingsystem,ithas
thefollowingrequirements:
Acleanableairlter
Aseawaterheatexchangerthatrequires50
GPMof22Corcoolerwater
A15horsepowercentrifugalblower
A240VAC(440,460or575)volt,60cycle
3-phaseexlosion-proofmotorwithassociated
ductingandaccessories
Ifspeciedandttedwithproperaccessories,the
motorsareCertiedforHazardousAreas.Whenutilizingdifferentaccessories,thesemotorsarealso
availableCertiedforHazardousAreaswithouta
totallyclosedcoolingsystem.
Special Handling Requirements
Youmustusespecialliftingdeviceswhenhandling
JOLIETdrillingmotorswiththeircoolingsystems
attachedtoavoiddamagingthecoolingandpurge
systems.Youmustnotlifttheentiremotorassembly
withtheliftingeyesontheheatexchangerorblower
assembly.Thiscandamagethecoolingandpurgesystem.
Grounding
s WARNING sPoorly grounded equipment can be a shock hazard.
You must ground the equipment before use. There is apotential for serious or fatal injury from electrical shock
if you do not properly ground electrical equipment.
Youmustprovidegroundingforthefollowingequip-
menttoprotectyourpersonnelfrompotentiallyhazard-
ousconditions:
Themotorframestoprotectyourpersonnelfrom
electricshockshouldtherebeaninsulation
failureinthemachine.
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Theconductorsbetweenthemachineframe
andtheadjacentsupportingstructureonwhich
apersonmaybestandingwhiletouchingthe
machine.
Note: This type of ground connection is referred to in elec-
trical standards as equipment grounding or enclosure
grounding which is not to be confused with system or cir-
cuit grounding. Drilling drive systems typically do not have
intentional circuit ground connections, except through high
impedance detectors.
Thedrillingunitsonwhichtheconstructionofthe
unitand/ortheinstallationofthemachinesdonot
inherentlyinsurepositivegroundingofthe
equipment.
Thisisrequiredinportable(modular)platformrigs
andlandrigswhichdonotalreadyhavegroundcables
toallmachinerystructures.Offshorerigswithequip-
mentfastenedtothedecksbyboltingorwelding
shouldnotrequireadditionalgrounding.(Forfurther
informationsee:ABSRulesforBuildingandClassing
SteelVessels,Section35.9.6,andIEEEStandard
45-1977,RecommendedPracticeforElectrical
InstallationsonShipboard,Section21.4.)
Thefollowingprocedureprovidesthestepstofollow
foreffectivelygroundingthemotor.
Note: We provide a 0.375 in. grounding stud on one of the
mounting feet you can use to connect the ground cable to
the drilling motor. Refer to the appropriate Outline drawing
for the stud location.
1. Preparea4/0sizeorlargercoppercableground
conductorlongenoughtorunfromthemotor
frametoeitheranexistinggroundconductor
systemorasuitableequipmentgroundpointas
denedbytheNationalElectricalCodeArticle250orotherapplicableregulation.(Forfurther
information,see:NationalElectricalCode,1978
Edition,Table250-95.)
2. Checkthatthesystemgrounddetectoris
connectedtothecommongroundpointforthe
rigandmaketheconnectionifnecessary.
3. Obtaintwocableterminalstot:
Thegroundcableonthedrillingmotorend
largeenoughforthe0.375diametergrounding
stud.
Theoppositeendofthecableandits
groundingconnection.
4. Installbothcableterminalstothecable.
5. Removepaint,rustandoilfromthesurfacesto
whichthecablesaretobeattached.
6. Connectbothcableterminalssecurely.
7. Usingadigitalohmmeter,checkthattheconnec-
tionsaresolid,lowresistanceconnectionsfrom
thecableconductortothegroundpointandto themotorframe.
Themeterreadingshouldbe0.2ohmsorless.
Lubrication
YoudonotneedtolubricateanyJOLIETdrillingmotor
designedforhorizontaloperationbetweenoverhaul
periods.Formoreinformation,seeOverhaul.
Special Tools
Thefollowingtableliststheitemsyourequireto
maintain,repairandoverhaulJOLIETdrillingmotors:
Tool Part
Megohmmeter 1,000 volts Fluke or equivalent
Voltmeter Multimeter
Resurfacing Stones
Medium Grade 8828492P11
Finish Grade 8828492P8
Brush-Seater Stone (White) 106X98
Hub Assembly Gauge 41D790941G1Hub Puller (less pump) 41B535703G1
Pump (for above) 8843947G1
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Caution: All models of JOLIET drilling motors require cooling. The cooling air should be free of combustible
gases which could be ignited by a spark. If you must run your equipment in these conditions, make sure you
provide an adequate supply of non-contaminated cooling air. If necessary, use a drill motor with provisions
for ducting suitable cooling air and containing other protective equipment such as spark arrestors.
Monthly Inspections
Thefollowingtableliststhetasksyoushouldperformaspartofyourmonthlyinspection.
Part Standard Operation Monthly Service
Exterior The exterior should be clean and damage-free.
Inspect the exterior of the machine, including cables, fordamage and replace as required.
Clean the exterior using clean, dry compressed air.
Covers, Seals, Latches The covers, seals and latches should beintact and operate properly.
Remove the inspection covers and ensure covers tproperly and cover latches work properly.
Clean the interior using clean, dry compressed air andblow the dirt and carbon dust from the machine.
Check exterior covers to ensure seals are intact;replace missing or damaged covers or seals asrequired.
Brushholders andBrushholder Sleeves
Brushholders and brushholder sleevesshould be damage free and be installedsecurely.
Inspect the brushholders for damage. If you mustreplace brushholder(s), see Brushholders, Workingwith the motor parts for more information.
Use a clean, lintless cloth and wipe dirt and grease from
the Teon brushholder sleeves; if necessary, use acleaner such as MEK (methyl ethyl ketone) to clean thesleeves. Be sure to follow standard safety precautionsfor handling a volatile solvent.
Inspect sleeves for cracks and thin spots caused byashovers. Replace any damaged brushholder or onehaving a damaged sleeve.
Inspect the brushholder cables and make sure allterminal bolts and all brushholder clamp bolts are tight.
Inspections
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Part Standard Operation Monthly Service
Brush Spring The brush spring should move freely and
brush spring pressure should be within
accepted pressure value limits.
Check for free movement of the spring assembly by
lifting the brush pressure ngers to the toggled-up
position.
Inspect brush springs for obvious failure or damage.
Check brush-spring pressure by comparing spring
pressure with a spring known to be good. For brush
spring-pressure value, see General Specications.
Brushes Brushes should be long enough to last until
the next inspection, be free of excessive
wear and be positioned correctly.
Check brushes for wear:
Lift the brush spring, remove the brush and measure
the brush length on the longest side from the top of
the carbon.
Ensure brushes have enough length to last until the
next monthly inspection. For more information on
brush length, see General Specications.
Check brushes for surface integrity:
Inspect all brushes to ensure the brushes are not
chipped or broken.
Inspect brush shunts to ensure they are not frayed or
broken.
Note: Brushes that are chipped, burned or rough-faced may
indicate that the commutator needs resurfacing.
Check brushes for positioning and connections:
Move the brushes up and down in their carbonways
to ensure brushes slide freely.
Check the brush shunts to be sure they are not
twisted or out of position.
Make sure all brush-shunt terminal connections and
all brushholder cable connections are tight.
Recommendation: We recommend you replace a brush that
shows any damage of any kind. We also recommend that if one
brush is showing wear, that you change all brushes at the same
time. For more information on installing brushes, see Brushes,
Working with the motor parts.
Inspections
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Part Standard Operation Monthly Service
Commutator The commutator should be clean, smooth,
glossy and free of high mica, high bars, at
spots or rough surfaces.
Inspect the commutator for possible ashover damage.
Verify that the commutator is perfectly round; if there
are indications that the commutator is out-of-round
(such as variations in the width of the ridge betweenbrush paths), check the concentricity of the commutator
with a dial indicator.
For more information on the condemning limits for
concentricity, see General Specications. If the commuta-
tor requires grinding, see Commutator, Working with the
motor parts and Resurfacing.
Creepage Band The creepage band should be clean and
installed tightly on the commutator cap.
Clean the creepage band (located on the commutator
cap) with a clean cloth dipped in an approved solvent.
Inspect the band for possible ashover damage.
Ensure the creepage band is installed tightly on thecommutator cap.
Flash Ring The ash ring should be clean and varnish-
free.
Examine the ash ring for possible ashover damage.
Wipe the ash ring clean with a clean cloth dipped in an
approved solvent.
Insulation The insulation should have a normal
resistance level and not show cracking.
Measure the insulation resistance with a megohmmeter;
if the reading is low, inspect the insulation to determine
if the cause is insulation failure or excessive moisture.
Correct the cause of the low readings before returning
the motor to service.
Inspect all accessible parts of the eld coil insulation for
cracking and evidence of overheating.
Power Cables The power cables should appear in good
condition.
Inspect the power cables for signs of excessive heating,
poor insulation or mechanical damage.
Ensure all power cable terminals are secured tightly.
Mounting Bolts All mounting bolts should be tight. Check all mounting bolts to ensure that they are
maintaining the correct bolt load.
Air Filters If applied, air lters should be free of
containments.
Inspect the air lter in the cooling system assembly.
Clean or change the lter as needed at each inspection.
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Inspection prior to Operation
Youshouldperformthefollowinginspectionsbefore
bringinganewJOLIETdrillingmotoron-line:
Removerodentguardsand/orducttapeoverthe airexitportsatthepinion-endofthemotor.
Removeandreversetheshipping/exhaustcover
priortooperation.
Verifythatallnecessaryequipmentblowersand
ductworkareinplaceandingoodcondition.
Removetheprotectionmaterialappliedtothe
commutatortopreventdamagewhilethemotor
wasintransit.
Removetheyellowarmaturelockingboltinstalled topreventmovementduringshipping,replaceit
withthesuppliedbolts,andre-torquetheboltto
100-120lbs-ft(seeFigure1below).
CAUTION: You must provide adequate cooling for
your JOLIET drilling motor. Without adequate cool-
ing, you could cause the equipment to overheat
which in turn could shorten equipment life and
negatively affect warranty coverage.
Inspections for Closed CoolingSystems
Thefollowingtableliststhetasksyoushouldperform
wheninspectingclosedcoolingsystems.
Time Period Activities
Every 7 days Check the three zinc anodes in the heat
exchanger; you should replace them as soon as
they start weeping water.
Every 30 days Check for air or water leaks; tighten all connec-
tions which may have become loose during
operation.
Every 90 days Inspect the carbon dust lter element. Ifrequired, clean the element with compressed
air, water or steam. Let the dust lter element
dry completely before you reinstall. Do not
clean using chemical solvents.
Semi-Annual Inspections
1. Performtheinspectionoperationslistedunder
MonthlyInspections.
2. Checktheclearancebetweenthebrushholders
andthecommutatorsurface.Forinformationon
brushholderclearancedimensions,seeGeneral
Specications.
3. Ifthedimensionsdonotmeettheminimum
requirements,adjustthebrushholderclearance.
Formoreinformation,seeBrushholders and
Brushes,Working with the motor parts,Adjusting
the Brush-holder Clearance.
Inspections
Yellow Armature Locking BoltsFigure1
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Recommendation: We recommend that you perform a
basic motor overhaul at least every two years, or 18,000
operating hours of normal operation. Exactly when you
perform an overhaul can vary, depending on the condi-
tion of the machine and your overall operation.
Thissectioncoversprocedurestodisassemble,
clean,inspect,repair,reassembleandtestthe
machine.
Testing the Motor before Disassembly
Thefollowingtableliststhetestsyoushouldperform
beforedisassemblingthemotor.
Test Description
Megohmmeter Test Determine the condition of the
insulation by:
1. Lifting the brushes.
2. Performing a megohmmeter
test on the armature windings
and eld coils.
If you receive a reading of less
than 2 megohms you should
check the quality of the insulation,
whether the insulation has
excessive dirt accumulation or
moisture.Bar-To-Bar Resistance Test Test for open or short-circuited
armature coils by:
1. Passing a regulated d-c current
through the armature coils.
2. Reading the voltage drop
between the commutator bars
with a millivoltmeter.
If you receive a reading that varies
more than 5% from the average
value, there is a defective or
short-circuited coil.
Disassembling the Motor
Removing the Hub
Useasuitablepullerwhenremovingahub.
Recommendation: We recommend a puller similar to Part
41B535703G1. This simple, efcient hydraulic puller uses
the oat method. A complete unit consists of a pump kit, a
backing plate, an adapter, a felt ring and a bolt.
Caution: Do not heat the hub before pulling it or use steel
wedges between the hub and bearing cap.
1. Removetheset-screwplugfromthetappedholeintheendoftheshaft.
2. Withthefeltringinplace,screwthebacking
platetotheendoftheshaftbyhand.Makethe
screwastightaspossible.Toprovidesufcient
clearanceforthehubtopopoff,backoffthe
backingplatetolineuptheslotwiththetapped
holeintheendoftheshaft.
3. Screwthepressure-ttingadapterintothehole
intheshaftuntilitseatsatthebottom.
4. Attachthepump.Screwtheconnectorononeendofthepressuretubeintotheadapter,and
theotherendintothepump.
5. Closethehandreliefvalveandworkthepump
handletoforceoilintothegrooveinthearma-
tureshaftunderthehub.Whenyouhavebuiltup
sufcientpressure,thehubwillpopofftheshaft
andbestoppedbythefeltwasherandbacking
plate.
Note: The capacity of the pump is 40,000 psi. It holds suf-
cient oil to remove eight to ten hubs. To ensure you have
sufcient oil, you should check the level at each use. When
required, remove the lling plug and rell with SAE-10
lubricating oil.
Motor Overhaul
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6. Openthereliefvalveandperformthefollowing
steps:
a.Disconnectthepumpfromtheadapter.
b.Removetheadapterandbackingplate fromtheshaft.
c.Liftoffthehub.
7. Whenthehubisoff,reinserttheplugtoprevent
cloggingthehole.
CAUTION: When either lifting the armature in
the vertical position or turning the armature to
a horizontal position, you should take special
precautions to avoid damage to the armature end-
windings, bearings or bearing ts, and the com-
mutator.
Removing the Armature From the Frame
Ifequippedwithcoolingsystemcomponents,remove
thembeforeproceeding.(Refertotherespective
suppliersinstructionsasnecessary.)
Beforeturningthemachinefromhorizontaltovertical
(orvice-versa),attachthearmaturelockingarrange-
menttopreventthearmaturefrommovingaxially.
Removethearmaturelockingarrangementbefore
operatingthemachine.
s WARNING sWhen using compressed air for cleaning purposes,ying debris and particles may present a hazard topersonnel in the immediate area. Personnel shouldbe provided with, and trained in the use of, personal
protective equipment as specied by applicable federalor state safety regulations.
1. Cleantheoutsideoftheframe,usingcom-
pressedair,asteam-jennyorcleaningsolvents,
toremoveaccumulateddirt.
2. Removethecouplinghubfromtheshaft,ifnot
alreadyremoved.
3. Removethecommutatorcovers.Disconnectand
removeallbrushes,andwrapheavypaper
aroundthecommutatorforprotectionduring
handling.
4. Removeboltsandwashers(41)whichholdthe
innerandouterbearingcapstothecommutator-
endframehead.Takeoffouterbearingcap(42)
andgasket(44).
5. Turnthemachineonendonastand,commuta-tor-enddown,andlevelitsothatthearmature
canbeliftedverticallyoutoftheframewithout
damagingthebearings,commutatoror
brushholders.
6. Screwthreeguidepinsintothecommutator-
endinnerbearingcap(46)tohelpguidethe
armatureoutoftheframe.Screwaliftingbail
ontothedriver-endoftheshaft.
7. Removedrive-endframeheadboltsandwash-
ers(8)andinsertjackscrewsinthethreadedholesprovidedintheframehead(7).
8. Lineupthehoistcablewiththecenterlineofthe
armaturebeforeengagingthehookinthelifting
bailontheendoftheshaft.Engagethehook
andliftslightly.Withsufcientstrainonthehoist
cabletotaketheweightofthearmatureoffthe
framehead,jackthedrive-endframeheadloose,
andliftthecompletearmatureassemblyoutof
theframe.DONOTDAMAGETHE
CUMMUTATOR.
CAUTION: Special precautions should be taken to
avoid damage to the armature end-windings, bear-
ings or bearing ts, and the commutator when lift-
ing the armature in the vertical position or turning
the armature to a horizontal position.
9. Placethearmaturehorizontallyinanarmature
saddleforbearingdisassembly.
10. Removethetwosetscrewsfromthesecuring
nutatthecommutator-endoftheshaft.
11. Removethenutfromtheendoftheshaftusinga
spannerwrench.
12. Installpullertoolandpulltheinnerraceofroller
bearing(50)fromthecommutator-endofthe
shaft.Sleeve(49)willcomewiththebearing.
13. Removeinnerbearingcap(46).
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14. Usingpullertool,pulltheoutersleeve(1)from
thedrive-endoftheshaft.Thesleevehas
tappedholesforapplyingthepuller.Heatmay
beapplied.
15. Removeboltsandwashers(3,4),andthen
removeouterbearingcap(2)andgasket(5).
16. Slideframehead(7)offtheshafttogetherwith
theouterraceandrollersofbearing(6).The
innerracewillremainontheshaft.
17. Pulltheinnerbearingraceofftheshaftwith
puller.
18. Removeslinger(9)andinnerbearingcap(10)
withpullerbyinsertingthefourpullerbolts
intothetappedholesininnerbearingcap(10).
19. Ifnecessary,removeinnersleeve(20)withpuller.
20. Presstheouterbearingraceandrollersfrom
theframeheadwithanarborpress.
Note: Before pressing the drive-end outer bearing race out of
the framehead, observe and record the number on the face of
the race. Mark the framehead in relation to the number. Rotate
90 degrees upon reassembly. After removal, mark the date
(with an electric pencil) under this number to indicate that this
position has been used. Reassemble the bearing with anothernumber opposite the mark. Etch the numbers 1, 2, 3 and 4
(spaced 90 degrees apart) on the face of race with an electric
pencil. Locate number 1 opposite the mark on the framehead
and mark it with the date.
21. Ifnecessarytoremovethecommutator-end
framehead(45),turntheframecommutator-
endupandremoveboltsandlockwashers
(43).Useboltsintheframeheadjack-out
holestobreakthetandremove.
Testing after Overhaul
Testing Series Models
Refertovendorpublicationsfortestingthecooling
systemsonmodelYZB(H).Afterthemotorhasbeen
reconditionedandreassembled,performthefollowing
teststoensureitoperatesasexpected.
InthistestyouwillconnectthemotortoaDCarc-
weldinggeneratorandrunthemachineseries-con-
nectedwithoutloadat900rpminordertomeasure
bearingtemperatures.
1. Useaputty,suchasDuxsealfromJohnsManvilleCompany,toholdthethermometerson
thedrive-endandcommutator-endouterbearing
caps.Forbestresults,thethermometersshould
contactthebearingcaps.
2. Seatthebrushesandrunfortenminutesat900
rpm.Theframetemperatureshouldnotrise
greaterthan25C.
3. Withthemachinerunninguptospeed,measure
thevibration.Thevibrationshouldnotexceed
0.1in/seconthecommutator-end.Ifthevibration exceedsthisvalue,rebalancethearmature.
4. Checkthecommutatorforroughnessandmake
surethebrushesareridingproperly.
5. Checkfornoisybearingsusingalisteningrod.
6. Stopthemachineandmountanindicatoronthe
frame.Whileturningthearmaturebyhand,
measurecommutatorrunout.Therunoutshould
notbegreaterthan0.001in.
7. Measuretheeldimpedance.With60HzACand24amperesthrougheacheld,measurethe
voltagedropacrosstotalexcitingandcommutat-
ingelds.Forvoltagelimits,seeGeneral
Specications.
s WARNING sTesting can be a shock hazard. Electric shock can
cause serious or fatal injury. Take proper precautionsduring testing.
8. Performahigh-potentialtesttothewindings oftheassembledmachine.Fordetailsonthe
highpotentialtest,seeGeneral Specications.
s WARNING sHigh potential testing can be a shock hazard. Electricshock can cause serious or fatal injury. Take proper
precautions during high potential testing.
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Testing Shunt Models
Refertovendorpublicationsfortestingthecooling
systemsonmodelYZE(K).Afterthemotorhasbeen
reconditionedandreassembled,performthefollowingteststoensureitoperatesasexpected.
Afterthemotorhasbeenreconditionedandreassem-
bled,performthefollowingteststoassureitwill
operatesatisfactorily.
Youconductthistestwiththemotorventilatedat2800
CFMatthecommutatorchamberwitha10HPblower.
1. ConnectthemotortoaDCweldinggenerator.
Refertoconnectiondiagram(Figure3)for
connections.
2. Runthemachinebyseparatelyexcitingtheshunt
eldfroma125VDCsource.Fromanother
sourceofpower,applyvoltagetothearmature
circuituntilyouhavereachedthedesiredspeed.
3. Holdseparateeldexcitationat57.5amperes.
Varythearmaturevoltagetoobtaintherequired
RPM.Atapproximately700terminalvolts(no
load),thespeedwillbe900RPM.
4. Ifthemotorisnotventilated,performthe
followingtest:
a. Holdtheseparateeldexcitationat10to
15amperes.Varythearmaturevoltageto
obtaintherequiredRPM.Atapproximately
338terminalvolts(noload),thespeedwill
be900RPM.
b. Runthemotorforveminutesat450RPM.
c. Increasethespeedto900RPMandrunfor
twohours.Thebearingtemperaturesshould
notexceed70C(158F).Rununtilthe
bearingtemperatureremainsconstantfor30
minutes.
d. Increasethespeedto1300RPMandholdit
whileperformingSteps2,3and4.Thenshut
downthemotor.Donotexceed1300RPM.
e. Measurethevibrationwhenrunningthe
motoruptospeed.Thevibrationshouldnot
exceed0.1in/secIfthevibrationexceeds
thisvalue,rebalancethearmature.
f. Checkthecommutatorforroughnessand
makesurethebrushesareridingproperly.
g. Checkfornoisybearingsusingalistening
rod.
h. Stopthemotorandmountanindicatoron
theframe.Turnthearmaturebyhandand
measurecommutatorrunout.Therunout
shouldnotbegreaterthan0.001in.
s WARNING sTesting can be a shock hazard. Electric shock can
cause serious or fatal injury. Take proper precautionsduring testing.
i. Measuretheinsulationresistanceofthewindingswithamegohmmeter.Iftheresis-
tancemeasuresmorethanonemegohm,
applyanAChighpotentialtesttogroundfor
oneminute.Fordetailsonthehighpotential
test,seeGeneral Specications.
s WARNING s
High potential testing can be a shock hazard. Electricshock can cause serious or fatal injury. Take proper
precautions during high potential testing.
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Cleaning
Toensureproperoperation,werecommendthe
followingmethodsforcleaningtheyourdrillingmotor.
Steam Cleaning
Youcanusethismethodforcleaningbothinsulatedandmetalparts.
1. Usesteamincombinationwithacommercial
non-causticcleaner.
CAUTION: Never use caustic soda solution on the
armature or coiled frame.
2. Suspendthepartinapositionwhereitcanbein
thedirectowofsteamfromthehosefromall
directions.
3. Rinseallresiduefromthepartsusingamixture
ofcleansteamandwater.
4. Bakeinsulatedpartsforatleast8hoursat
150C(302F)toremoveallmoisture.
Vapor Degreasing
Youcanusethismethodjustformetalparts.
1. Bringthecleaningsolutiontoaboil,andallow
thevaporlineinthetanktorisetothecondensercoilsatthetopofthetank.
2. Keepthevaporizedcleaningsolutionatabout
120C(248F).
3. Lowertheparttobecleanedintothevapor-
ladenatmosphere,sothevaporwillcondenseon
thepart.
4. Tospeedtheremovalofheavydirtaccumula-
tions,sprayhotsolutiondirectlyfromthetank
ontothepartbeingcleaned.Thetemperatureof
thesolutionmustbekeptbelowitsboilingpoint.
5. Removethecleanedpartfromthedegreaser.
6. Drainandcoolthepart.
Cleaning Anti-Friction Bearings/ShaftTapers/Bearing Fits
Youcanuseacleaningsolutionthatleavesanoillm
toprotectnishedsurfacesfromrust.Kerosene,petroleumspiritsorotherpetroleum-basedcleaners
providelimitedprotectionforthesesurfaces.
g
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The Brushes and Brushholders
Replacing the Brushes
Youshouldcheckthebrushspringpressurebefore
replacingbrushes.Thebrushspringpressureis
pre-setandnon-adjustableforthebrushholdersused
onthesemachines.Ifyouhaveabrushholderthatis
eitherdamagedorhasalowspringpressure,you
shouldreplaceitbeforeinstallingnewbrushes.You
measurespringpressurewitha20-lb.springscale
pullingradiallyonthebrushpressurengeroverthe
centerofeachbrush.Forinformationonlimits,see
General Specications.
Recommendation: When replacing brushes, we recom-
mend you use only the brush grades listed in the GeneralSpecications. If you mix brush grades in the same motor or
change brushes to another grade you can seriously affect
commutation, surface lm, commutator and brush life.
Removing the Brushes
Usethefollowingproceduretoremovebrushes.
1. Removethecommutatorinspectioncovers.
2. Disconnectthebrushshuntfromtheterminal
screwlocatedonthebrushholderbody.
3. Liftthepressurengerawayfromthebrushto
thetoggled-upposition.
4. Removethebrush.
5. Usedry,compressedairtoblowthecarbon
dustfromthecarbonway.
s WARNING s
Using compressed air for cleaning purposes can raisedebris and ying particles. Wear safety glasses and otherpersonal protective equipment when using compressedair for cleaning purposes. Flying debris and particles
may also present a hazard to personnel in the immediatearea. Improper protection can result in serious injury.
Installing the Brushes
Usethefollowingproceduretoinstallbrushes.
1. Insertanewbrush;ensurethatthebrush
slidesfreelyinthecarbonway.
2. Carefullylowerthespring-loadedbrush
pressurengeronthebrush.
Caution: Do not allow the nger to snap down on
the brush as this can chip and damage the brush.
3. Attachthebrush-shuntterminalstothe
brushholderbodyunderthescrewsprovided.
Arrangethebrushshuntstrandssothatthey
clearthepressurengers.
4. Cleantheterminalsandtightentheterminal
screw(s).
Caution: Make sure brush shunts are not posi-
tioned under the pressure ngers.
5. Checkandtightenallbrushholdercable
connections.
6. Seatthenewbrusheswithawhiteseater
stone.
7. Installthecommutatorcoversonthemotorand
checkforpropertandlatchoperation.
Replacing the Brushholders
Usethefollowingproceduretoremovethe
brushholder.
1. Removebrushesfromthebrushholders.
2. Coverthecommutatorwithheavypaper.Youwill
leavethepaperonthecommutatortoprotectit
untilyouhaveinstalledthenewbrushholder.
3. Disconnectthecablefromthebrushholder(s)
youareplanningtoremove.
4. Removethebolt,washerandbrushholderclamp.
5. Liftthebrushholderoutoftheframe.
Working with the Motor Parts
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Installing the Brushholders
Usethefollowingproceduretoinstallthebrushholder.
1. Positionthebrushholderintheframewiththe
brushholderstudsrestingintheclampsurfacesofthebrushholdersupport.
2. Installtheboltandwasher.Tightentheboltbut
donottorquetheboltuntilyouhavedetermined
thebrushholder-to-commutatorclearance.For
moreinformation,see Adjusting the Brushholder
Clearance.
3. Afteryouhavesetthebrushholderclearance,
connectthebrushholdercableandremovethe
protectivepaperfromthecommutatorsurface.
4. Checkthebrushestoinsurethattheyexceed
theminimumbrushlengthdimensionandare
freeofanydamage.Youcanreusethemif
theyarelongenoughandarenotdamaged.
Ifnot,youshouldreplacethemwithnew
brushes.
Adjusting the Brushholder Clearance
Usethefollowingproceduretoadjustthebrushholder
clearance.
1. Removethebrushes.
Caution: Do not allow the brushholder to touch,
bump or rest on the commutator.
2. Inserta1/16in.berspacerbetweenthebottom
ofthebrushholderandthecommutator.Youmay
havetoloosenthebrushholderifthegapisless
than1/16in.
Caution: Do not use a metal spacer.
3. Loosenthebrushholderclampboltsandmove
thebrushholderssotheytouchtheberspacer.
4. Tightentheclampboltsto225-250lbs-ft.torque.
Removethespacerandrecheckthebrushholder
clearancegaptoensureitis1/16in.
5. Connectthecableleadstothebrushholder
terminalsandtightentheterminalbolts.
Inspecting and Testing the Brushholders
Performthefollowingstepswheninspectingand
testingbrushholders.
1. Checkthebrushholderforashoverdamage,
cracksandburnedorpittedareas.
2. Checkthebrushspringstoensuretheymove
freelyanddonotbind.
3. Insertanewbrushinthecarbonwayandmove
itupanddowninthecarbonwaytobesureit
movesfreely.
Replacedamagedbrushholdersiftheyaredamaged
orshowsignsofexcessivewear.Formoreinformation,
seeReplacing Brushholders.
Replacing the Brushholder Sleeves
Usethisproceduretoreplacebrushholdersleeves.
1. RemovethedamagedTeonsleevefromthe
brushholderstudbyheatingthebrushholderin
anovento150C(302F)thenpeelingor
cuttingthesleevefromthestud.
s WARNING s
Wear safety glasses and leather gloves at all times whenworking with equipment heated to extreme temperatures.
Improper protection can result in serious injury.
2. Thoroughlycleanthesurfaceofthestudto
removeanybuild-upofcarbonordirt.
3. HeatanewTeonsleeveina150C(302F)
ovenfor15minutes.
4. Immediatelyassemblethehotsleeveonthe
stud.
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Reassembling the Brushholders
Usethisproceduretoreassemblethebrushholder.
1. Usingaboltandwasher,attachthebrushholder
clamptotheframemount.
2. Positionthestudsofthebrushholderinthe
clamp,andmovethebrushholderradially
outwardasfaraspossible.
3. Tighten,butdonottorque,thebrushholder
clampbolt.Formoreinformationontheproper
lubricationofassemblyhardware,see
Lubricating Bolts.
4. Installallbrushholders.Formoreinformation,
see Installing the Brushholders.
5. Connectthebrushholdercables.
The Armature
Inspecting and Testing the Armature
Toavoiddamagetothecore,banding,endturns,
shafttsandcommutator,handlethearmaturecareful-
lyduringinspectionandtesting.Forfurtherprotection:
Supportthearmatureinasaddletoprotectthe
commutatorandthecoilends.
Coverthecommutatorwithheavypaperuntil
youcompletedallworkonthearmature.
Usethisproceduretoinspectandtestthearmature:
1. Bringthearmaturetoroomtemperature,25C
(77F).
2. Performadielectrictestofthearmatureinsula-
tionusinga500or1000VDCmegohmmeter.
Youwantareadingofonemegohmorhigher.
Ifyougetavaluelowerthanonemegohm
performthefollowingactionstoincreasethe
resistancevalueoftheinsulation:
a. Performadditionalcleaningandbaking
operations.
b. Replacethecreepageband.
c. Rewindthearmature.
3. Measureandrecordthearmatureresistance.
Forresistancevalues,see General
Specications.
4. Iftherearenogroundedarmaturecoils,
performabar-to-barcomparisontesttocheckforopenorshort-circuitedarmaturecoils.
a. PassaregulatedDCcurrentthroughthe
armaturecoils.
b. Readthevoltagedropbetweenthe
commutatorsegmentswithamillivoltmeter.If
thereadingvariesmorethan5%,youhave
adefectiveorshort-circuitedcoil.
5. Ifthearmaturefailsthebar-to-bartest,you
mustrewindthearmature.
Replacing the Armature Creepage Band
Werecommendyouusethehotbondprocesswhen
replacingthearmaturecreepageband.Thisprovides
superioradhesionpropertieswhenattachingthe
Teoncreepagebandontheouterendofthecom-
mutator.Youreceiveacopyofthisprocessineach
TeonBandKit(PartNo.76518).Youcanorderthekit
fromJolietPartsatinfo@joliet-equipment.com.
Assembling the Armature into the Frame(Models YZE, YZK, ZE-F, ZK-F, ZE, ZK)
Usethisproceduretoassemblethearmatureintothe
frameformodelsYZE,YZK,ZE-F,ZK-F,ZE,ZK:
Note: For information on the proper lubrication of assembly
hardware, see Lubricating Bolts.
1. Assemblethebrushholders(51)intotheframe.
a. Positionthebrushholderwellbackfromthe
commutatortokeepthemclearfromthe
commutator.
b. Fastenandinsulatetheconnectionsand
installoutgoingcables.
2. Assemblethecommutator-endframehead(45)
totheframe.
a. Tightenboltsandwashers(43)uniformly.
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b. Torqueboltsto45050lbs-ft.
3. Usingaheavydutystand,blockandlevelthe
frameinaverticalposition,commutator-end
down.
4. Assemblealiftingbailontothedrive-endofthe
shaft.
5. Wrapheavypaperaroundthecommutatorto
provideextraprotection.
6. Installthebearingpilotonthethreadsofthe
commutator-endoftheshaft.
7. Withthebearingpilotandthecommutator-end
bearinginnerraceassembledontotheshaft,
lowerthearmaturepartwayintotheframe.Use
thebearingpilottoaligntheshaftwiththecenterofthebearing.Lowerthearmatureinto
theframeuntilthedrive-endframeheadstarts
intotheframet.
8. Insertthedrive-endframeheadboltsand
washers.
a. Removeanyburrsordirtbetweenthets
oftheframeheadandthemagnetframe.
b. Drawdowntheboltsandwashersuniformly
topressthearmatureintoplace.Makesure
todrawthemdownevenlytoavoidcocking thebearingassemblyanddamagingthe
races.
CAUTION: Uneven tightening of bolts could dam-
age bearings or related tted surfaces.
9. Torqueframe-headbolts(43)to45050lbs-ft.
10. Removethebearingpilot.
11. Removethecommutator-endbearingcap(42).
12. Usingafeelergauge,checktheradialclearance
betweentherollersandtheinnerraceonthe
commutator-endbearing.Theassembled
clearancemustmeasurebetween0.001and
0.003in.
13. Placethemachineinahorizontalposition.
14. Checkthecommutator-endbearingrunout.
a. Withthetipagainsttheouterraceofthe
bearing,clampanindicatortothe
commutator-endoftheshaft.
b. Toeliminateend-playanddetermineifthe
outerraceistrue,pushthearmature
towardthecommutator-end.Iftheouterraceisoutmorethan0.003in.,besure
thatthedrive-endframeheadboltsare
pulleduptightandthatthereareno
burrsordirtbetweenthetsoftheframe
headandthemagnetframe.
c. Assemblethethrustringontotheendof
theshaft.Positionittightlyagainstthe
bearinginnerrace.
d. Usingan18-in.spannerwrench,assemble
theretainingnutontotheendoftheshaft.
e. Firmlytaptheendofthewrenchwitha
10-lb.bronzehammeruntilthenutstops
turning.Ifyouhaveatorquewrench
available,torquethenutto500lbs-ft.
f. Locktheretainingnut(48)byassembling
andtighteningtwosetscrews(47)witha
torquewrenchsetto38to42lbs.-ft.Ifa
suitabletorquewrenchisnotavailable,
tightenthesetscrewswithastandard
Allenwrenchbyrmlytappingthe
wrenchwitharawhidemalletuntilthe
screwsstopturning.Theimpression
madebythesesetscrewsintheshaft
lockstheretainingnutinplace.
g. Lockthesetscrewsbyprick-punching
thethreadsintwoplaces.
h. Pack2.8oz.ofgreaseintotheouter
circumferenceofthebearingcap(42).
i. Placethegasket(44)intopositiononthe
outerbearingcap(42);assemblethecaptotheframehead(45)withboltsand
lockwashers;andtightenboltsto110to
120lbs-ft.
15. Checkthedrive-endbearingrunout.
a. Removethedrive-endouterbearingcap
(2)andcheckthealignmentoftheouter
bearingracebyclampinganindicatorto
theshaft.
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b. Iftheouterracerunsoutmorethan0.004
in.,besuretherearenoburrsordirt
betweentheregistertsoftheframe
headandthemagnetframeandthatthe
frameheadboltsarepulleduptight.
16. Usingafeelerguage,checktheradialclearance
betweenthedrive-endbearingrollersandthe
innerrace.Theassembledclearanceofthe
drive-endbearingmustbebetween0.0012and
0.004in.
a. Withthebearing(6)andcap(10)properly
lledwithgrease,andthegaskets(5)in
place,assembletheouterbearingcap(2)
andtightenthebolts(3)to110to120lbs-ft.
b. Heattheoutersleeve(1)to110C(230F)
andshrinkitontotheshaftuntilitistight againsttheinnerraceofthebearing.
17. Usingadialindicator,checkthearmature
end-play;end-playshouldmeasure
between0.006and0.010in.
Assembling the Armature into the Frame
(Models YZB, YZH, ZB-F, ZH-F, ZB, ZH)
Usethisproceduretoassemblethearmatureintothe
frameformodelsYZB,YZH,ZB-F,ZH-F,ZB,ZH:
Note: For information on the proper lubrication of assembly
hardware, see Lubricating Bolts.
1. Assemblethebrushholders(51)intotheframe.
a. Positionthebrushholderwellbackfromthe
commutatortokeepthemclearfromthe
commutator.
b. Fastenandinsulatetheconnectionsand
installoutgoingcables.
2. Assemblethecommutator-endframehead (45)totheframe.
a. Tightenboltsandwashers(43)uniformly.
b. Torqueboltsto46727lbs-ft.
3. Usingaheavydutystand,blockandlevelthe
frameinaverticalposition,commutator-end
down.
4. Assemblealiftingbailontothedrive-endofthe
shaft.
5. Wrapheavypaperaroundthecommutatorto
provideextraprotection.
6. Withthecommutator-endbearingandbearing
housingassembledontotheshaft,lowerthe
armatureintotheframeuntilthebearinghousingenterstheframehead.Continuetolowerthe
armatureintotheframeuntilthedrive-endframe
headstartsintotheframet.
7. Insertboththedrive-endandcommutator-end
frameheadboltsandwashers.
a. Removeanyburrsordirtbetweenthets
oftheframeheadandthemagnetframe.
b. Drawdowntheboltsandwashersuniformly
topressthearmatureintoplace.Makesure
todrawthemdownevenlytoavoidcocking thebearingassemblyanddamagingthe
races.
CAUTION: Uneven tightening of bolts could dam-
age bearings or related tted surfaces.
8. Placethemachineinahorizontalposition,
tightenallframeheadbolts(41)andtorquebolts
to46727lbs-ft.
9. Pack5.25oz.ofgreaseintotheoutercircumfer-
enceofbearingcap(42).
a. Placethegasket(44)inpositiononthe
bearingcap.
b. Assemblethecaptotheframehead(45)
withboltsandlockwashers(41,43).
c. Torquebolts(41)to110to120lbs-ft.
10. Checkthedrive-endbearingrunout.
a. Removethedrive-endouterbearingcap
(2)andcheckthealignmentoftheouter
bearingrace.
b. Clampanindicatortothedrive-endofthe
shaftwiththetipagainsttheouterraceof
thebearing.
c. Pushthearmaturetowardthedrive-endto
eliminateend-playandrotatethearmature
toseeiftheouterraceistrue.Iftheouter
racerunsoutmorethan0.004in.,besure
therearenoburrsordir tbet weenthe
registertsoftheframeheadandthe
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magnetframeandthattheframehead
boltsarepulleduptight.
11. Withafeelerguage,checktheradialclearance
betweenthedrive-endbearingrollersandthe
innerrace.Theassembledclearanceofthe drive-endbearingmustbebetween0.0012and
0.004in.
a. Withthebearing(6)andcap(10)properly
lledwithgrease,andthegaskets(5)in
place,assembletheouterbearingcap(2)
andtightenbolts(3)to110to120lbs-ft.
b. Heattheoutersleeve(1)to110C(230F)
andshrinkitontotheshaftuntilitistight
againsttheinnerraceofthebearing.
12. Usingadialindicator,checkthearmature end-play;end-playshouldmeasurebetween
0.006and0.010in.
Removing the Armature LockingArrangement
Usethisproceduretoremovethearmaturelocking
arrangement:
1. Removethetwoshippingboltsfromthebearing
cap.Theseboltshaveyellowheadsandare
longerthantheotherbolts(seeFigure1).
2. Installthetworegularbolts.Theregularboltsareinabagattachedtooneoftheshippingbolts.
3. Torquetheregularboltsto115lbs-ft.
Note: Put the shipping bolts back in the bag and save them
in case you need to lock the armature at a later date.
Locking the Armature for Shipment
Locatethebagwhereyouhavetheshippingboltsand
usethisproceduretolockthearmatureforshipping:
1. Removetwodiametricallyoppositeboltsinthe
commutator-endbearingcap.
2. Installtheshippingbolts(thelongerboltswith
theheadspaintedyellow,asshowninFigure1)
withjamnutsapplied.
3. Torquetheboltsto30lbs-ft.andtightenthe
jamnuts.
Caution: Do not rotate the armature when the
locking bolts are in place. This can damage the
bearings and the commutator.
4. Placethetworegularboltsinthebagandattach
thebagtooneoftheshippingbolts.
Testing the Armature After Repair
Onceyouhavecompletedallworkonthearmature,
usethisproceduretotestthearmaturebeforebringing
itbackintoservice:
1. Applyahighpotentialtestvoltagebetweenthecommutator(withallsegmentsshorted)andthe
shaftbasedonthefollowingcriteria:
Usedarmature-2000volts,60Hzforone
minute
Rewoundarmature-3500volts,60Hzforone
minute
s WARNING s
High potential testing can be a shock hazard. Electric
shock can cause serious or fatal injury. Take properprecautions during high potential testing.
Note: Measure leakage current to ground during test 3-85.0
milliamps.
2. Conductaresistancemeasurement.Forthe
armatureresistancevalue,seeGeneral
Specications.
Yellow Armature Locking BoltsFigure1
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Armature Varnish Treatment
Afteryouhaveeithercleanedandrepairedorre-
woundthearmature,itmustbevacuumpressure
impregnated(VPI).
Balancing the Armature
Dynamicallybalancethearmaturewithin10grams
(0.35oz.)onthedrive-endand12grams(0.42oz.)on
thecommutator-endbyaddingweightsonthecommu-
tatorcapandthearmaturehead.
Inspections
Inspecting the Insulation
Inspecttheinsulationofarmaturecoilsforcracks,physicaldamage,burnsanddeterioration.Replaceor
repairtheinsulationasrequired.
Glass Band,Commutator-endInspecttheglass
bandsforsplittingorfraying;ensurethereareno
looseconnections.
Wire Band,Drive-endInspectthewirebandfor
physicaldamage,loosetieclipsorbrokenwire.
Creepage Band Inspectthesurfaceofthe
Teoncreepagebandforpossibleashover
damage.Tapthebandlightlyandcheckfor movement.Youmustreplacethebandifitisloose
orhasdeepburns.Formoreinformation,see
Replacing the Armature Creepage Band.
Inspecting the Commutator
Checkthecommutatorforthefollowingconditions:
Overallappearancetoensurethe
commutatorisfreeoftreading,pitting,
grooving,burns,atspots,highbarsand
copperdrag.
Concentricitytoensurethatthecommutator
isnotout-of-round.Forconcentricitylimits,
see General Specications.
Propersizetoensurethediameterofthe
commutatoriswithintheallowablesize
range.Fortheminimumpermissible
commutatordiameterdimension,see
General Specications.
Properalignmenttoensuretherearenohighbars
(thecommutatorisnotloose).
Whenrequired,resurfacethecommutator.Formoreinformation,seeResurfacing the Commutator.
Note: If after resurfacing, the brush surface diameter will
be less than the minimum permissible diameter, you must
replace the commutator.
Inspecting the Armature Shaft Bearing Fits
Comparethearmatureshaftbearingtdimensionsto
ensuretheyarewithinthefollowingtolerances:
+ 0.0000
- 0.0008
5.9077 BEARING
FIT PE
+ 0.0000
- 0.0008
5.1203 DIA. BRG.
FIT OPE
(Double Shaft)
+ 0.0000
- 0.0007
3.9389 DIAM.
(BRG. FIT) OPE
Ifthedimensionsarenotwithinthetolerancesyou
mustrepairorreplacethearmatureshaft.
Inspecting the Creepage Band
Inspectthecreepagebandforthefollowingconditions:
Nogapsshouldbevisibleatthejointorbetween
theedgeoftheTeonbandandthecopperbars.
Thebandsurfaceshouldbesmooth,freeof
varnishandbondedtotheunderlaymaterial.
NobubblesshouldappearundertheTeon.
Thebandshouldhavenobuckling.
Thesurfaceshouldbefreeofdamageandnot havescratchesorcuts.
Replacethecreepagebandwhenrequired.
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Resurfacing the Commutator
Beforeturningorgrindingthecommutator,youmust
ensurethereissufcientstocksothecommutatorwill
notbeturnedorgroundbelowtheminimumpermissi-
blediameter.SeeGeneral Specicationsforthe
minimumpermissiblecommutatordiameterdimension.
Formoreinformation,seePreparing the Commutator
for Resurfacing.
Note: If after resurfacing, the brush surface diameter will
be less than the minimum permissible diameter, you must
replace the commutator.
s WARNING s
Resurfacing operations can raise dust and ying parti-cles. Wear safety glasses and a respirator for protectionfrom dust and ying particles during resurfacing opera-
tions. Improper protection can result in serious injury.
Grinding
Usethefollowingproceduretogrindthecommutator:
1. Truetheshaftcenterswithrespecttothebearing
tsbyscraping.
2. Placethearmatureeitherinalatheequipped
withagrindingattachmentorinagrinding
machine.Checktheconcentricityofthebearing
ts.TheTIRshouldnotexceed0.001in.
3. Coverthearmaturewindingstokeepitclear
fromdebris.
4. Grindthecommutatorandcheckthecommuta-
torrunoutwithadialindicator.Themaximum
commutatorrunoutis0.001in.
5. Performtherequiredundercutting,rakingandpolishing.
Turning
Ifthesurfaceofthecommutatorisbadlyworn,burned
orscarred,itrequiresturning.Usethefollowing
proceduretoturnthecommutatorinalathe:
1. Truetheshaftcenterswithrespecttothebearing
tsbyscraping.
2. Placethearmatureinalatheandcheckthe
concentricityofthebearingts.TheTIRshould
notexceed0.001in.
3. Coverthearmaturewindingstokeepitclear
fromdebris.
4. Setthecuttingtoolforturningcopper,andset
lathespeedtogivethecommutatorasurface
speedof300feetperminute.
5. Makeclean,smoothcutstoremovejustenough
coppertorenewthecommutatorsurface.Donot
allowthecuttingtooltochatter.Forthedimen-
sionsofthedustgroove,see General
Specications.
6. Afteryouhavecompletedtheturning,checkthe
commutatorrunoutwithadialindicator.The
maximumcommutatorrunoutis0.001in.
7. Performtherequiredundercutting,rakingand
polishing.
Undercutting
Youcanuseahacksawbladetoundercutthecom-
mutator.Werecommendyoukeepthebladesharp;as
thebladedullsitcanproducesmallcracksinthemica
wheredirtormoisturecanbuildupandbreakdownthe
insulationbetweenthecommutatorsegments.With
practice,youcanuseahand-heldpowerundercutter.
Whenusingapowerundercutter,followthetool
manufacturersinstructionsanduseslotguidesanddepthgaugestoensureaccurate,uniformcuts.We
recommendyoutakeafewpracticepassesovera
scrapcommutatortogetabetterunderstandingon
howthetoolreacts.Youmustkeepthepowerunder-
cutterfromjumpingoutoftheslotandacrossthe
commutatorsurface;thehigh-speedoperationofthe
bladewillquicklygougethecommutator.
Afteryouhaveresurfacedthecommutator,usethis
proceduretoundercutthecommutator:
g
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1. Undercutthemicabetweenthebarstoadepth
of0.047in.Youshouldperformtheundercutting
withasharp-edgedtoolhavingacuttingwidthof
0.063in.
2. Blowloosematerialoffthecommutatorwithdry,compressedair.
s WARNING s
Using compressed air for cleaning purposes can raisedebris and ying particles. Wear safety glasses and otherpersonal protective equipment when using compressed
air for cleaning purposes. Flying debris and particles mayalso present a hazard to personnel in the immediate area.
Improper protection can result in serious injury.
Raking
Resurfacingtypicallyleavesparticlesandsliversof
coppereitherhangingonthebaredgesorlodgedin
theundercutslots.Theseparticlescanbridgetheside
micaandcauseaashover.Toensuresafeoperation,
youmustremoveparticlesbeforeyoucanplacethe
motorbackinservice.
Usethisproceduretorakethecommutator:
1. Usingastiff-bristlenylonbrush,brushoutany
loosedirtorcoppersliversattachedtothe
trailingedgeofthebars.Youcanalsouseanew
paintbrushorstencilbrushwiththebristlescut
shorttoaddstiffness.
2. Ifstoningandundercuttingpulledalargeamount
ofcopperfromtheedgesofthebars,useeither
arakingtoolorapieceofberboardapproxi-
mately0.045in.thicktoremovethecopperns
andraggededges.Whenusingarakingtool,use
thetooltorakethebaredgeswiththepoint
insertedintheslotsothatsidesofthetoolrake
thetrailingedgeofthebar.Ifthetoolisground
withatsidesandusedwithmoderatepressure,itwillremoveraggedcoppernsandbreakthe
sharpedgesofthebars.
3. Aftertheslotshavebeenraked,usenesandpa-
pertosandthecommutatortoremoveadditional
smallpiecesofcopperattheedgesoftheslots.
4. Thoroughlycleanthearmaturecoreand
commutatorwithdry,compressedairtoremove
copperanddust.
s WARNING sUsing compressed air for cleaning purposes can raise
debris and ying particles. Wear safety glasses and otherpersonal protective equipment when using compressed
air for cleaning purposes. Flying debris and particles mayalso present a hazard to personnel in the immediate area.
Improper protection can result in serious injury.
Polishing
Ifthecommutatorisdiscoloredorsmudged,usethis
proceduretopolishthecommutator:
1. Usingcanvas,crocuscloth,ne(4/0)sandpaper
or400ATriemitepaper,polishthecommutator.If
youareusingabrasivepaper,youshouldmount
itonawoodenblockcurvedtotthesurfaceof
thecommutator.
CAUTION: Never use an emery cloth on a com-
mutator. The abrasive particles on emery cloth
scratch the commutator surface and lodge in the
grooves between commutator segments. This can
create conditions that can eventual lead to ash-
over which could seriously damage the machine.
2. Blowloosematerialoffthecommutatorwith
dry,compressedair.
s WARNING s
Using compressed air for cleaning purposes can raisedebris and ying particles. Wear safety glasses and otherpersonal protective equipment when using compressed
air for cleaning purposes. Flying debris and particles mayalso present a hazard to personnel in the immediate area.
Improper protection can result in serious injury.
3. Checkthecommutatorconcentricitywithadial
indicator.Fortherun-outlimits,seeGeneral
Specications.
4. Coverthecommutatorwithheavypaperorfeltto
protectitfromdamageuntilyouarereadyto
bringitbackintoservice.
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The Motor Frame
Inspecting and Testing theMotor Frame
Usethefollowingproceduretoinspectandtestthe
motorframe:
1. Inspectthefollowingelementsofthemotorframe:
a. Checktheconnectionstrapinsulationand
theinsulationonthecoilsfordamage,signs
ofburning,cracksordiscoloration.
b. Checktheleadcablesfordamage,
overheatingandsignsofdeterioration.
2. Replaceanymotorframepartsthatfailthe
inspection.Formoreinformation,see
Replacing the Motor Frame Field Coil.
3. Performthefollowingtests:
a. Conducta1,000voltmegohmmetertest
onthecoilsandlookforareadingof20
megohmsormore.
b. Measureandrecordcommutatingand
exciting-coilresistance.RefertoTable1to
determinethecorrectconnectiondiagramfor
themachinebeingrepaired.
c. High-potentialtesttheeldcoilstogroundby applyingahigh-potentialtestof3,400VDC,
60Hzforoneminute.
s WARNING s
High potential testing can be a shock hazard. Electricshock can cause serious or fatal injury. Take proper
precautions during high potential testing.
4. Replaceanymotorframepartsthatfailtesting.
Formoreinformation,seeReplacing the Motor
Frame Field Coil.
Replacing the Motor FrameField Coil
Youperformthefollowingstepswhenyoureplacethe
motorframeeldcoil:
RemovingtheCoil
InstallingtheCoil
ContactJOLIETEquipmentCorporationtodetermine
thecorrectcoiledframeassemblydrawingforthe
machinebeingrepaired.
Removing the Coil
1. Removeterminalinsulationanddisconnectthe
coilleads.Useeitheragastorchorbrazingtongstoseparatethebrazedconnections.When
youareusingbrazingtongs,uselowvoltageand
highACcurrenttoheatthecoilconnections.
s WARNING s
Brazing requires extremely high temperatures. Wearsafety glasses and leather gloves at all times duringbrazing operations. Improper protection can result in
serious injury.
2. Packabsorbentbotharoundtheinsulationnearthecoilconnectionandovertheadjacentcoils.
Note: If you are using a gas torch, protect the coil insulation
from the heat using a non-ammable heat absorbent, such
as interwoven glass cloth.
3. Ensureallexposedinsulationiscoveredwitha
thicklayerofabsorbent,thenheatandseparate
thecoilconnections.
4. Softenthevarnishinordertoremovethepole
boltsbyheatingthecoiledframeinanovenat
150C(302F)forfourhours.
5. Removethepoleboltsandthecoil-poleassem-
blyfromthemagnetframe.
6. Markanyshimsforreassemblywiththecorre-
spondingpolewhenthecoil(s)isinstalledinthe
frame.
p
g
g
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Installing the Coil
Youmustinstallanyexcitingcoilsandbrazetheir
connectionsbeforeyoucaninstallcommutatingcoils.
Formoreinformation,seeBrazing the Coil Terminals.
Usethefollowingproceduretoinstallnewcoil-pole
assemblies:
1. Cleanboththepolecontactsurfaceonthe
frameandthepolepiecemountingsurface.
2. Installthenewpoleandcoilintheframewith
NomexInsulatorandanyshimsthatwereonthe
damagedcoil.Replaceoldwashersunderthe
boltheadswithnewwashers.
3. Lubricatetheboltheads,threadsandwashers
anddrawthepoleboltsmoderatelytight.
4. Brazethecoilconnections.Formoreinforma-
tion,seeBrazing the Coil Terminals.
Brazing the Coil Terminals
Youmustbrazeallcoilconnectionswithsilversolder,
JECAG101.Usetwopiecesofsolder(0.010x1in.x1
in.)betweentheterminalsurfaces.Youcanbrazethe
coilterminalsusingeitherthemachinebrazingmethod
orthegastorchmethod.
Using the Machine Brazing Method
Usethefollowingproceduretobrazethecoiltermi-
nalsusingmachinebrazing:
1. Setthebrazingcurrentto10,800amperesat
1.6volts.
2. Insertsilver-solderbrazingstripsbetween
connections.
3. Clampthebrazingtongsontheconnectionand
brazethejoint.Ifnecessary,addadditionalsoldertollthejointandformalevelsurface.
4. Brazeallexciting-coilconnections.When
complete,youcaninstallthecommutating
coils.
Using the Gas Torch Brazing Method
Usethefollowingproceduretobrazethecoiltermi-
nalsusingthegastorchbrazingmethod:
1. Packthecoilinsulationwithnon-ammableheatabsorbentmaterialsuchasinterwovenglass
cloth.
2. InsertthebrazingstripsanduseaC-clampor
vise-gripplierstoclamptheconnectionsurfaces
tightlytogether.
3. Useatorchtipwitha0.1in.oriceandadjust
thetorchtoobtainaslightlyreducedame.
4. Meltthebrazingstrips;astheymelt,addmore
soldertollthejointandformalevelsurface.
5. Removetheheatabsorbentpackingfromthe
insulation.Usedry,compressedairandblow
outtheinsideoftheframe.
s WARNING s
Using compressed air for cleaning purposes can raisedebris and ying particles. Wear safety glasses and otherpersonal protective equipment when using compressed
air for cleaning purposes. Flying debris and particles mayalso present a hazard to personnel in the immediate area.
Improper protection can result in serious injury.
6. Torquethepolebolts.Formoreinformation,see
Standard Torque Values.
7. Checkthepolarityoftheeldpoles;energizethe
eldcircuitwithabatteryandcheckthepole
polaritywithacompass.
8. Insulatetheconnectionswithsiliconeputtyand
wraptheconnectionswithMylarlm.
9. Usingglasstape,wraptheconnectionsothat
theglasstapeextends1/2inchbeyondthebareareaoftheconnection.
10. Installandconnectanycablesthatyou
previouslyremoved.
11. Flooddipthecoiledframe.Youcanood-dipthe
coiledframeonlyafteryouhaveinsulatedthe
connectionsandinstalledanycablesyouhad
previouslyremoved.Formoreinformation,see
Flood Dipping the Coiled Frame.
Braz
ingtheCoilTer
minals
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Flood Dipping the Coiled Frame
Youinsulatethecoiledframebyooddippingonly
afteryouhaverepairedorreplacedtheeldcoilsand
havecompletedallelectricaltests.
Youusevarnishforooddipping.Forbestcoverage,
agitatethevarnishfor15minutesbeforedippingthe
frame.
Usethefollowingproceduretoooddipthecoiled
frame:
1. Checkthatyouhavemadeallcoilconnections;
thattheconnectionsareproperlyinsulated,and
thatallcablesandtiesforcablesandconnection
strapsareinplace.
2. Tiecableendsabovethevarnishlevel.
3. Coatallmachine-tsurfaceswitheitherblack
varnishorstrippingcompoundandplugbolt
holeswithdummybolts.
4. Heatthecoiledframeto40-80C(104-176F)
anddiptheframedrive-enddown(withallcoil
connectionscovered)foratleast15seconds.
5. Drainandremovetheframefromthevarnish
andallowtheframetodrainforatleast5min-
utesinaverticalposition,drive-enddown.
6. Pre-heattheovento150C(302F)andbake
theframebasedonthevarnishmanufacturers
specications.
7. Cleanthevarnishfromallmachinedsurfaces
andunplugthetappedholes.
Testing the Coiled Frame
Testing after Repair (without Armature)Usethefollowingproceduretotestthecoiledframe
(withoutarmature)afterrepair:
1. Pass24.0amperes(60Hzcurrent)throughthe
exciting(series)eldandreadthevoltagedrop.
Itshouldbewithinthefollowingrange:
MinimumVolts13.1
MaximumVolts15.6
2. Pass24.0amperes(60Hzcurrent)throughthe
commutating(CP)eldandreadthevoltage
drop.
Fornon-magneticretainersitshouldbeinthe
followingrange:
MinimumVolts7.3
MaximumVolts8.5
Formagneticretainersitshouldbeinthefollow-
ingrange:
MinimumVolts10.7
MaximumVolts12.4
Testing After RepairUsethefollowingproceduretotestthecoiledframe
afterrepair:
1. Applyahighpotentialtestvoltageaccordingto
thefollowingcriteria:
Usedcoils2000volts,60Hzforone
minute
Newcoils3500volts,60Hzforone
minute
Duringthistest,measureleakagecurrenttoground;themaximumallowableleakageis5.0
milliamps.
s WARNING s
High potential testing can be a shock hazard. Electricshock can cause serious or fatal injury. Take proper
precautions during high potential testing.
2. Conductaresistancemeasurement.Forthe
resistanceoftheexcitingandcommutating
elds,seeGeneral Specications.
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The Connection Boxes
Changing the Position of the
Connection Box
Youcanchangetheconnectionboxonamachine
fromonesidetotheother.
Usethefollowingproceduretochangeaconnection
boxforseriesmotorsfromtherightsideofthemachine
totheleftside.Therearedifferencesinworkingwith
theF1andF2cableswhenchangingthepositionof
theconnectionboxesonshuntmotors.Formore
information,seeDifferences for Shunt Motors.
Note: To change the connection box from the left side of the
machine to the right side, reverse the specic side-orientedsteps.
1. Disconnectallaccessoriesfromtheconnection
box.
2. Removetheconnectionboxcovers.
3. DisconnecttheF1,F2,A1andA2leadsfromthe
connectionbox.
4. Loosenthestrainreliefconnectorsatthebottom
oftheboxandremoveallcablesandconduitfromthebottomofthebox.
5. Disconnecttheblowerandheaterleadsfromthe
terminalboard,theblowerandheaterconduit
andttingsfromtheconnectionbox,andremove
theleads.
6. Disconnectthepressurizingassemblyandtting
fromtheconnectionbox.
7. Disconnectthepressuresensingtubefromthe
rearoftheconnectionbox.
8. Removethemountingboltsandlifttheconnec-
tionboxoffoftherightsideofthemotor.
9. Removethepressuresensingtubeandtting,
theheaterconduitandtting,andthepressuriz-
ingconduitandttingfromtheright
sideofthecommutatorchamber.
10. Removethepipeplugsfromtheleftsideofthe
commutatorchamberandinstallthepipeplugs
inmatchingholesontherightside.
11. Removetheheaterleadsandheaterfromthe
commutatorchamber.
12. ChangetheF1andF2leadsfromtherightside
totheleftsideusingthefollowingsteps:
a. Removethelowersplashguardsfrom
thedrive-endofthemotor.
b. RemovetheinsulationfromtheF1and
F2connectionsinsideofthemagnet
framethroughtheairoutletholes.
c. Removetheboltsfromtheconnections
andremovetheF1andF2externalleads
fromtheelbowinthemagnetframe.
d. Removetheelbow.
e. Insulatethebareterminalsleftinthe
magnetframeand,ifnecessary,tie
downtheleads.Formoreinformation,
seeInsulating the Terminal Connections.
f. Removethepipeplugfromtheleftside
offrameandinstallintheholevacated
bytheelbowandtheF1andF2leads.
g. RemovetheinsulationfromtheF
terminalsinsideofthemagnetframeon
theleftsidethroughtheairoutlethole.
h. InstalltheelbowandtheF1andF2leads
intheholeontheleftsideofthemagnet
frame.
i. ConnecttheF1andF2leadstothecorrect