Hobart Welding Products 250 Troubleshooting − Lack Of Penetration, Troubleshooting − Burn-Through

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6-11. 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.

6-12. 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.

 

 

6-13. 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-192 440 Page 36

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Contents OM-192 440W ProcessesDescription File MIG GmawFrom Hobart to You Table of Contents Warranty Symbol Usage Marks a special safety messageArc Welding Hazards Electric Shock can killARC Rays can burn eyes and skin Welding can cause fire or explosionFlying Metal can injure eyes Buildup of GAS can injure or killCalifornia Proposition 65 Warnings EMF Information Principal Safety StandardsAbout Pacemakers LES Fumées ET LES GAZ peuvent être dangereux UNE Décharge Électrique peut entraîner la mortIndique un message de sécurité particulier LE Soudage peut provoquer un Incendie ou une explosionDES Particules Volantes peuvent blesser les yeux DES Pièces Chaudes peuvent provoquer des brûlures gravesRisque D’INCENDIE OU D’EXPLO LA Chute DE L’APPAREIL peut blesser’EMPLOI Excessif peut SUR DES Organes Mobiles peuvent provoquer des blessuresPrincipales normes de sécurité En ce qui concerne les stimulateurs cardiaquesSpecifications Welding Power Source Duty Cycle And OverheatingExceeding duty cycle can damage unit and void warranty OverheatingVolt-Ampere Curves Welding Gun Duty Cycle And OverheatingDefinition Installing Welding Gun Connecting To Weld Output Terminals Installing Work ClampSetting Gun Polarity For Wire Type Installing Wire Spool And Adjusting Hub TensionInstalling Gas Supply Rear PanelPositioning Jumper Links VoltsElectrical Service Guide Hz SingleInput Voltage Min Grounding Conductor Size In AWGSelecting a Location And Connecting Input Power Threading Welding Wire WoodTurn Off unit, and disconnect input power OperationConnecting Spool Gun To Welding Power Source Turn Off unit− Operation ControlsWeld Parameters Voltage switch positionWhile welding Example 2/40 = To read settingsNumber on left of slash Routine Maintenance Disconnect power before maintainingSupplementary Protectors MonthsTurn Off power Replacing Drive Roll And Wire Inlet GuideRemoving Knob From Front Panel Turn Off power before replacing contact tip Replacing Gun Contact TipTurn off welding power source/wire feeder Wire size stamped on tip − check and match wire sizeReplacing Switch And/Or Head Tube Welding Troubleshooting Table Wire Drive/Gun Troubleshooting TableWire Drive/Gun Trouble Remedy Welding Trouble Remedy− MIG Welding Gmaw Guidelines Typical MIG Process ConnectionsTypical MIG Process Control Settings Wire Size Amperage RangeThickness to Amperage a AmperageHolding And Positioning Welding Gun Conditions That Affect Weld Bead Shape Good Weld Bead Characteristics Poor Weld Bead CharacteristicsGun Movement During Welding Troubleshooting − Excessive Spatter Troubleshooting − PorosityTroubleshooting − Excessive Penetration Possible Causes Corrective ActionsTroubleshooting − Incomplete Fusion Troubleshooting − Lack Of PenetrationTroubleshooting − Burn-Through Troubleshooting − Waviness Of Bead Troubleshooting − DistortionTroubleshooting Guide For Semiautomatic Welding Equipment Wire does not feedCommon MIG Shielding Gases ApplicationWelding arc not stable Wire slipping in drive rolls OM-192 440 − Electrical Diagram − Parts List REGULATOR/FLOWMETER, 10−50 CFH ARGON/CO2 Center Baffle w/Components Center Baffle w/Components -1Item Rear Panel w/Components Front Panel w/Components M-25 Gun Optional Spool Gun Switch Description RemarksPage Support ServiceAssistance Contact your Distributor for Hobart Welding Products