MG MG6 Series 2011 - Collision Repair; Description and Operation; General Welding Precautions

CollisionRepair
BodyRepair
CollisionRepair
DescriptionandOperation
GeneralWeldingPrecautions
General
Foreaseofreference,thediagramsonthefollowingpages
showonlythetypeofweldusedinrepairwhereitvariesfrom
thatusedinproduction.
Thereplacementweldsintheweldingdiagramsaredenoted
bythefollowingsymbols:
A.=Single/Multiplethicknessplugwelds
B.=MIGseamweld
Whencarryingoutweldingoperationsthefollowingcriteria
mustbeobserved:
•Whereresistancespotweldshavebeenusedin
production,thesemustbereproducedwithnew
spotweldsinreplacementwherepossible.Allsuch
reproductionspotweldsmustbespaced30mmapart.
•Whenspotwelding,itisrecommendedthattestcoupons
ofthesamemetalgaugesandmaterialsareproducedto
carryoutpeelteststoensurethatweldingequipment
beingusedcanproduceasatisfactoryjoint.Plugwelds
mustbeusedifasatisfactoryspotweldcannotbe
produced.
•Theelectrodearmsonhand-heldspotweldinggunsmust
notexceed300mminlength;
•Single-sidespotweldingisnotacceptable.
•Gasweldingandbrazingarenotacceptable.MIGbrazing
isthepreferredmethod.
•Where3metalthicknessesormorearetobewelded
togetheritisimperativetouseMIGplugweldstoensure
jointstrength.
•MIGplugweldsmustbeusedinrepairjointswherethere
isnoaccessforaresistancespotwelder.T oreplaceeach
productionspotweld,an8mm(approx.)holemustbe
drilledand/orpunched,andaMIGplugweldthenmadein
itsplace.Thenumberofplugweldsmustmatchexactly
thenumberofspotweldswhichhavebeenremoved.
•Whereholesareleftinanexistingpanelafterremoval
ofthespotwelds,asingleMIGplugweldwillbemadein
eachholeasappropriate.
ElectronicControlUnits
TheElectronicControlUnits(ECU)ttedtovehiclesmake
itadvisabletofollowsuitableprecautionspriortocarrying
outweldingrepairoperations.Harshconditionsofheatand
vibrationmaybegeneratedduringtheseoperationswhich
couldcausedamagetotheunits.
Inparticular,itisessentialtofollowtheappropriate
precautionswhendisconnectingorremovingtheairbag
DiagnosticControlUnit(DCU).
SupplementaryRestraintSystemPrecautions
Anyworkundertakenwhichinvolvestheremovalor
replacementofanyitemoftheSupplementaryRestraint
System(SRS),requiresextremecautionandadherencetothe
appropriateprecautions.
Equipment
Priortocommencinganytestprocedureonthevehicle,ensure
thattherelevanttestequipmentisworkingcorrectlyandany
harnessorconnectorsareingoodcondition.Thisparticularly
appliestoelectroniccontrolunits.
SeatBeltAnchorages
Seatbeltanchoragesaresafetycritical.Whenmakingrepairs
intheseareas,itisessentialtofollowdesignspecications.
NotethatHighStrengthLowAlloy(HSLA)steelmaybeused
forseatbeltanchorages.
Wherepossible,theoriginalproductionassemblyshouldbe
used,completewithitsseatbeltanchorages,orthecutline
shouldbesoarrangedthattheoriginalseatbeltanchorageis
notdisturbed.
Allweldswithin250mmofseatbeltanchoragesmustbe
carefullycheckedforweldquality,includingspacingofspot
welds.
PanelReplacementProcedure
Thisprocedureisdesignedtoexplainthebasicpanelremoval
andreplacementmethod.Themaincriterioninremovaland
replacementofbodypanelsisthattheoriginalstandardis
maintainedasfaraspossible.Whileindividualrepairswilldiffer
indetail,thisprocedurehasbeendevisedplacingemphasison
easeofrepairandtheeliminationofunnecessarywork.
Bodypanelsarebeingincreasinglymanufacturedinhigh
strengthsteelstomeetdesignrequirementsforsafetyand
weightsaving.Aspanelsinhighstrengthsteelscannotbe
visuallyidentied,andastheyaremoresensitivetoexcess
Version2.0837