Farr HD8625 - Troubleshooting; A. TONG WILL NOT DEVELOP SUFFICIENT TORQUE

Technical Manual
hD8625 8-
5
/
8
” 35K Tong
4.1
TroubleshooTing
Adequatemaintenanceandproperfluidselectionisessentialforminimizinghydraulic-relatedfailures.Alltroubleshootingmustbeperformed
byatechniciantrainedinhydraulicsystems,andfamiliarwiththeequipmentdesign,assemblyandoperation.
Thefollowing troubleshootinginstructionsareintendedtobeguidelinesonly. Anyfaultsnotsolvedthroughtheuseofthisguideshouldbe
referredtoourengineeringdepartmentfortheirevaluationandrecommendations.
A. TONG WILL NOT DEVELOP SUFFICIENT TORQUE
MCCOY DRILLING & COMPLETIONS GUARANTEES CALIBRATION OF A LOAD CELL/TORQUE GAUGE
ASSEMBLY FOR A PERIOD OF ONE YEAR. MCCOY SUGGESTS THAT THE LOAD CELL/TORQUE
GAUGE ASSEMBLY BE RETURNED TO THE FACTORY FOR RE-CALIBRATION ON A YEARLY BASIS.
POSSIBLE PROBLEM SOLUTION(S)
1
Malfunctioningreliefvalveontonghydrauliccircuit SeeSection4.B,ReliefValveTroubleshooting
2 Directionalvalveisleaking
Checkdirectionalvalve.Neutralpositionshouldreturnfluiddirectlytothereservoir.
Replaceorrepairvalvetoensurecorrectoperation
3 Powerunitisnotproducingadequatepressure Troubleshootpowerunit(seeuser’smanualforyourparticularunit)
4
Poorhydraulicpressureatthe tong despiteade-
quate pressure at the power unit, or excessive
backpressureinthereturnline.
Restrictionsexistinlinebetweenpowerunitandtong.Inspectintegrityofself-seal-
ingcouplingstoensuretheyareallowingfullfluidflow.Checktoensurenoother
restrictionsexist(contaminatedcatchscreensorfilters,forexample)
5
Fluidviscosityisnotappropriate(too high or too
low)
EnsurehydraulicfluidbeingusedistheviscosityrecommendedbyMcCoyDrilling&
Completions.Powerunitpumpmaynotprimeiffluidistooheavy,andthehydraulic
systemwilloverheatiffluidistoolight.Replacewithproperviscosityfluid
Hydraulic fluid viscosity is affected by environmental conditions. Ensure the fluid
beingusedissuitableforhighorlowtemperatures.Replacewithproperviscosity
fluidfortheoperatingconditionsifnecessary
6 Wornordamagedtongmotorcausingslippage Replaceorrepairwornordamagedmotor
7
Damaged bearings or gears causing excessive
drag
Replaceorrepairwornordamagedgearsorbearings
8 Jawsslippingonpipe
Ensurejawdiesarenotworntothepointthattheycannotgrip.Ensurethecorrect
sizedjawsareinuse
9 Torquegaugeisindicatingincorrectly
Incorrectgauge is being used. Ensuregauge is the proper range,andhas been
properlycalibratedforthearmlengthoftheequipmentinuse
Gaugehasbeendamaged.Checkgaugeoperationandcalibrationonindependent
system
Gaugehasmistakenlybeenmarriedtoanincorrectloadcell
10 Loadcellismeasuringincorrectly
Incorrectloadcellisbeingused
Airistrappedintorquemeasuringcircuit(loadcell,hydraulicline,orgauge.Refer
totorquemeasurementtroubleshootinginSection6ofthismanual
Loadcellhasbeendamaged.Replaceloadcell,orreturntoMcCoyforrepairand
re-calibration
POSSIBLE PROBLEM SOLUTION(S)
11
Incorrectmotorspeedselected(appliesto2-speed
motorsonly)
Maximumtorque can only bedeveloped when LOW motor speed(maximum hy-
draulicdisplacement)isselected.
12 Incorrecttonggearselected MaximumtorquecanonlybedevelopedwhenLOWmotorgearisselected