Hobart Welding Products OM-944 196 639G, 175 manual Troubleshooting − Lack Of Penetration

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8-11. 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.

8-12. 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.

8-13. 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.

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OM-944 Page 37

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Contents Description OM-944Processes From Hobart to You Table of Contents Options and Accessories Warranty Marks a special safety message Symbol UsageArc Welding Hazards Electric Shock can killWelding can cause fire or explosion ARC Rays can burn eyes and skinFlying Metal can injure eyes Buildup of GAS can injure or killCalifornia Proposition 65 Warnings About Pacemakers Principal Safety StandardsEMF Information − Consignes DE Sécurité − À Lire Avant Utilisation Identifie un message de sécurité particulierLES Particules Projetées peu- vent blesser les yeux LE Soudage peut causer un incen- die ou une explosionLES Pièces Chaudes peuvent cau- ser des brûlures graves LE Bruit peut affecter l’ouïeLA Chute DE L’APPAREIL peut blesser Risque D’INCENDIE OU D’EXPLO’EMPLOI Excessif peut Faire LES Pièces Mobiles peuvent cau- ser des blessuresConsignes relatives aux stimulateurs cardiaques Principales normes de sécuritéInformation sur les champs électromagnétiques VAC Model − SpecificationsSpecifications Output Duty Cycle And OverheatingDuty Cycle % Output AmperesLoad Amps Volt-Ampere CurvesInstalling Welding Gun Installing Work Clamp − InstallationChanging Polarity Process/Polarity TableInstalling Gas Supply Rating Label = GND/PE Do not move or operate unit where it could tipInstalling Wire Spool And Adjusting Hub Tension Electrical Service Guide For 230 VAC ModelHold wire tightly to keep it from unraveling Threading Welding WireControls − OperationWelding Guide Weld Parameter Chart For 115 VAC ModelFor 115 Volt Wire Welding Package Weld Parameter Chart For 230 VAC Model For 230 Volt Wire Welding Package Routine Maintenance − Maintenance &TROUBLESHOOTINGDisconnect power before maintaining Overload Protection 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 Trouble Remedy Troubleshooting TableCircuit Diagram For 115 VAC Model − Electrical DiagramCircuit Diagram For 230 VAC Model Typical MIG Process Connections − MIG Welding Gmaw GuidelinesWire Size Amperage Range Typical MIG Process Control SettingsThickness to Amperage a Select VoltageHolding And Positioning Welding Gun Conditions That Affect Weld Bead Shape Gun Movement During Welding Poor Weld Bead CharacteristicsGood Weld Bead Characteristics Troubleshooting − Porosity Troubleshooting − Excessive SpatterTroubleshooting − Excessive Penetration Possible Causes Corrective ActionsTroubleshooting − Burn-Through Troubleshooting − Lack Of PenetrationTroubleshooting − Incomplete Fusion Troubleshooting − Distortion Troubleshooting − Waviness Of BeadApplication Troubleshooting Guide For Semiautomatic Welding EquipmentCommon MIG Shielding Gases Welding arc not stable Wire slipping in drive rolls Return To Table Of Contents Main Assembly − Parts ListDia Part H-10 Gun 195 Optional Drive RollsOptions Page Support ServiceHobart Welding Products Contact your Distributor for