Lincoln Electric 4000 manual Welding Cast Iron, Cast Iron Plate Preparation

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B-18

OPERATION

B-18

 

 

 

4.The bead should be put on with a weaving motion, and it should be 1/2-3/4” (12.7-19.0mm) wide. Do not let the arc blow over the edge, as that will dull the edge. (See drawing below.)

Work Table

Strike Arc

 

Here

Sharp Edge

Brick

 

 

 

Plow Share

 

1/2-3/4" width

 

(12-20mm)

 

 

Positioning of Share

Weaving Motion

5.Use the back-stepping method. Begin to weld 3” (76mm) from the heel of the share and weld to the heel. The second weld will begin 6” (152mm) from the heel, the third weld 9” (229mm) from the heel, etc.

B

A

C

D

E First weld from A to B; then

 

 

3"

 

 

 

 

 

 

from C to A; then from D to C;

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

then from E to D; and so on.

(75mm)

 

 

 

 

 

 

 

 

 

BACKSTEPPING

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Backstepping greatly reduces the chances for crack- ing of the share, and it also greatly reduces warping.

NOTE: The entire process is rather fast. Many begin- ners go much too slowly when hardfacing plowshares, running the risk of burning through the thin metal.

Welding Cast Iron

When welding on a piece of cold cast iron, the tremendous heat from the arc will be absorbed and distributed rapidly into the cold mass. This heating and sudden cooling creates WHITE, BRITTLE cast iron in the fusion zone. (See drawing below.)

When breaking the weld stays on one piece

To overcome this, the welding operator has two choices:

1.Preheat the entire casting to 500-1200°F (260- 649°C). If the cast iron is hot before welding, there will be no sudden chilling which creates brittle white cast iron. The entire casting will cool slowly.

2.Weld 1/2” (12.7mm) at a time, and do not weld at that spot again until the weld is cool.

This way, no large amount of heat is put into the mass.

Most inexperienced welders will probably use the sec- ond method, because they have no way of preheating large castings. Smaller castings can easily (and should) be preheated before welding. A forge, stove, fire, or the Arc Torch are all excellent means of pre- heating.

When using the 1/2” (12.7mm) at a time method, it is recommended to start 1/2” (12.7mm) away from the previous bead and weld into the previous bead. This is called backstepping.

After welding Cast Iron, protect the casting against fast cooling. Put it in a container of warm, dry sand or lime.

If sand or lime is not available, cover it with sheet metal or any other non-flammable material that will diminish drafts and retain heat.

hot

coldcold

White brittle cast iron

Cast Iron Plate Preparation

This is the reason why welds in cast iron break. Actually, one piece of the broken cast iron has the entire weld on it and the other piece has no weld on it. (See drawing below.)

Wherever practical, the joint to be welded should be “veed” out by grinding or filing to give complete pene- tration as shown in figures (a), (b) and (c) below. This is especially important on thick castings where maxi- mum strength is required.

POWER-ARC 4000

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Contents POWER-ARC California Proposition 65 Warnings SafetyElectric Shock can kill Iii Welding Sparks can cause fire or explosionPrécautions DE Sûreté On-Line Product Registration Please Examine Carton and Equipment For Damage ImmediatelyMaster Table of Contents for ALL Sections Technical Specifications POWER-ARC InstallationLocation and Ventilation Safety PrecautionsStoring Engine Exhaust can killPRE-OPERATION Engine Service Muffler Deflector Power-Arc 4000 Typical Fuel ConsumptionSpark Arrester 8 HP Carb. Certified 9 HP Honda 9 HP Kool Bore PlusElectrical Output Connections Welding Cable ConnectionsCable Size and Length Cable Installation Auxiliary Power ReceptaclesMachine Grounding Plugs and HAND-HELD EquipmentCircuit Breakers Premises WiringType Common Electrical Devices Possible Concerns Table A.2 Electrical Device USE with the POWER-ARCOperation Safety InstructionsOperating Instructions General DescriptionDesign Features Advantages Operational Features and ControlsRecommended Applications Welding CapabilityGENERATOR/WELDER Controls Controls and SettingsGasoline Engine Controls Engine Operation Before Starting the EngineStarting the Engine Stopping the Engine Running the EngineBREAK-IN Period General Information Generator OperationTable B.3 Generator Power Applications Control Function / Operation Current Control Dial Welding OperationWelding Guidelines Material Thickness Electrode Type Size SettingStick Welding Welding arc What Happens in the Arc?Correct Welding Position Correct Arc Length Correct Way to Strike An ArcCorrect Welding Speed Types of Welds Common MetalsUse the following Do the followingFillet Welds PenetrationMultiple Pass Welds Welding in the Vertical PositionVertical-Down Welding Vertical-Up WeldingOverhead Welding How to Hardface the Sharp Edge Metal to Ground WearWelding Sheet Metal Hardfacing To Reduce WearCast Iron Plate Preparation Welding Cast IronOut-of-Position Group AWS E6011 Selecting ElectrodesHigh-Speed Group AWS E6013 Low Hydrogen Group Stable-Arc E7018Accessories OPTIONS/ACCESSORIESLincoln Electric Accessories Routine and Periodic Maintenance MaintenanceEngine Maintenance Engine AdjustmentsFigure D.2 Clean Rotating SCREEN/FINGER GUARD/DEBRIS Guard Table D.1 Engine Maintenance Parts PartHonda Figure D.5. Brush Removal and Replacement GENERATOR/WELDER MaintenanceFigure D.6. Major Component Locations HOW to USE Troubleshooting Guide TroubleshootingPossible Areas SymptomsTroubleshooting Engine requires service to head, head gasket, and/or valves Diagrams Wiring Diagram Power ARC 4000 Codes 10671 4000 POWER-ARC POWER-ARC Precaucion Warnung
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