Miller Electric MW 140 Plus Troubleshooting − Lack Of Penetration, Troubleshooting − Burn-Through

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9-11. Troubleshooting − Lack Of Penetration

 

 

 

 

 

Lack Of Penetration − shallow

 

 

 

 

 

 

 

 

 

 

fusion between weld metal and

 

 

 

 

 

 

 

 

base metal.

Lack of Penetration

Good Penetration

 

 

 

 

 

S-0638

 

 

 

 

Possible Causes

 

 

Corrective Actions

 

 

 

Improper joint preparation.

 

Material too thick. Joint preparation and design must provide access to bottom of groove while

 

 

 

 

maintaining proper welding wire extension and arc characteristics.

 

 

 

Improper weld technique.

 

Maintain normal gun angle of 0 to 15 degrees to achieve maximum penetration.

 

Keep arc on leading edge of weld puddle.

 

 

 

Be sure welding wire extends not more than 1/2 in (13 mm) beyond nozzle.

 

 

Insufficient heat input.

Select higher wire feed speed and/or select higher voltage range.

 

 

 

Reduce travel speed.

 

 

Incorrect polarity.

Check polarity required by welding wire, and change to correct polarity at welding power source.

9-12. Troubleshooting − Incomplete Fusion

 

 

Incomplete Fusion − failure of weld metal to fuse completely with

 

 

base metal or a preceeding weld bead.

 

 

S-0637

 

 

 

 

 

 

 

Possible Causes

 

Corrective Actions

 

 

 

Workpiece dirty.

 

Remove all grease, oil, moisture, rust, paint, undercoating, and dirt from work surface before

 

 

welding.

 

 

 

Insufficient heat input.

 

Select higher voltage range and/or adjust wire feed speed.

 

 

 

Improper welding technique.

 

Place stringer bead in proper location(s) at joint during welding.

 

 

 

 

 

Adjust work angle or widen groove to access bottom during welding.

 

 

 

 

 

Momentarily hold arc on groove side walls when using weaving technique.

 

 

 

 

 

Keep arc on leading edge of weld puddle.

 

 

 

 

 

Use correct gun angle of 0 to 15 degrees.

 

 

 

9-13. Troubleshooting − Burn-Through

Burn-Through − weld metal melting completely through base metal resulting in holes where no metal remains.

S-0640

Possible Causes

Corrective Actions

 

 

Excessive heat input.

Select lower voltage range and reduce wire feed speed.

 

 

 

Increase and/or maintain steady travel speed.

 

 

OM-219 316 Page 34

 

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Contents →Description OM-219 316CProcesses 2006−10Page Table of Contents − Parts List Arc Welding Hazards Symbol UsageMarks a special safety message Electric Shock can killFlying Metal can injure eyes ARC Rays can burn eyes and skinWelding can cause fire or explosion Buildup of GAS can injure or killCalifornia Proposition 65 Warnings About Pacemakers Principal Safety StandardsEMF Information Indique un message de sécurité particulier UNE Décharge Électrique peut entraîner la mortLES Fumées ET LES GAZ peuvent être dangereux DES Particules Volantes peuvent blesser les yeux LE Soudage peut provoquer unIncendie ou une explosion DES Pièces Chaudes peuvent provoquer des brûlures graves’EMPLOI Excessif peut SUR Risque D’INCENDIE OU D’EXPLOLA Chute DE L’APPAREIL peut blesser DES Organes Mobiles peuvent provoquer des blessuresPrincipales normes de sécurité En ce qui concerne les stimulateurs cardiaquesSpecifications − SpecificationsSymbols And Definitions − DefinitionsOutput Duty Cycle % WarrantyDuty Cycle And Overheating Exceeding duty cycle canVolt-Ampere Curves AmperageIncorrect − InstallationInstalling Welding Gun CorrectProcess/Polarity Table Changing PolarityInstalling Gas Supply CO 2 gas regulator/flowmeterSelecting a Location And Connecting Input Power Do not move or operate unit where it could tipInstalling Wire Spool And Adjusting Hub Tension Installing 8 in 203 mm Wire SpoolInstalling Contact Tip And Nozzle Flux NozzleThreading Welding Wire Hold wire tightly to keep it from unraveling− Operation ControlsWeld Parameter Chart 217 618-A Overload Protection − Maintenance &TROUBLESHOOTINGRoutine Maintenance Drive Motor ProtectionReplacing Gun Contact Tip Changing Drive Roll Or Wire Inlet GuideTurn Off power before replacing contact tip To Reassemble Gun Cleaning Or Replacing Gun LinerDisconnect gun from unit Replacing Switch And/Or Head Tube Does not run Troubleshooting TableTrouble Remedy − Electrical Diagram Circuit Diagram− MIG Welding Gmaw Guidelines Typical MIG Process ConnectionsThickness to Amperage a Typical MIG Process Control SettingsWire Size Amperage Range Select VoltageHolding And Positioning Welding Gun Conditions That Affect Weld Bead Shape Gun Movement During Welding Poor Weld Bead CharacteristicsGood Weld Bead Characteristics Troubleshooting − Excessive Penetration Troubleshooting − Excessive SpatterTroubleshooting − Porosity Possible Causes Corrective ActionsTroubleshooting − Burn-Through Troubleshooting − Lack Of PenetrationTroubleshooting − Incomplete Fusion Troubleshooting − Waviness Of Bead Troubleshooting − DistortionCommon MIG Shielding Gases Troubleshooting Guide For Semiautomatic Welding EquipmentWire does not feed ApplicationWelding arc not stable Wire slipping in drive rolls − Parts List Main AssemblyDia Part Description Quantity Dia Part Description Quantity Mkgs H-10 Gun 195Optional Drive Rolls OptionsWarranty Owner’s Record