Lincoln Electric 5000 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. In some instances a back-

POWER ARC 5000

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Contents Power ARC Safety Depends on YouSafety California Proposition 65 WarningsElectric Shock can kill Welding Sparks can cause fire or explosion IiiPrécautions DE Sûreté Sûreté Pour Soudage a L’ArcThank You Please Examine Carton and Equipment For Damage ImmediatelyTable of Contents Installation Technical Specifications Power ARCLocation and Ventilation Safety PrecautionsStoring Tilting StackingLifting Assembly of Wheels and Handle to the Tube Frame Fuel PRE-OPERATION Engine ServiceOIL Spark ArresterElectrical Output Connections Welding Cable ConnectionsCable Installation Auxiliary Power ReceptaclesMachine Grounding Plugs and HAND-HELD Equipment Power Cord Connections to TWIST- Lock PlugsPremises Wiring Circuit BreakersThese Devices Without Operating Instructions Safety InstructionsOperation General DescriptionWelding Capability Recommended ApplicationsLimitations Controls and Settings GENERATOR/WELDER ControlsFigure B.2 Gasoline Engine Controls Gasoline Engine ControlsBefore Starting the Engine Engine OperationStarting the Engine For a HOT Engine Stopping the EngineBREAK-IN Period For Best Engine StartingGenerator Operation To USE the Generator AS AN Auxiliary Power SupplyGeneral Information Table B.3 Generator Power Applications Suggested Power Applications Running Watts Start-up WattsControl Function / Operation Current Control Dial To USE the Power ARC 5000 for Stick WeldingWelding Operation After YOU Finish the WeldWelding Guidelines Stick Welding What Happens in the Arc? Figure B.4 The welding arcCorrect Way to Strike An Arc Correct Welding Position Correct Arc LengthCorrect Welding Speed Common Metals PracticeTypes of Welds Multiple Pass Welds PenetrationFillet Welds Welding in the Vertical PositionVertical-Up Welding Vertical-Down WeldingWelding Sheet Metal How to Hardface the Sharp Edge Metal to Ground WearOverhead Welding Hardfacing To Reduce WearWelding Cast Iron Cast Iron Plate PreparationHigh-Speed Group AWS E6013 Selecting ElectrodesOut-of-Position Group AWS E6011 Low Hydrogen Group Stable-Arc E7018Lincoln Electric Accessories AccessoriesOPTIONS/ACCESSORIES Briggs and Stratton AccessoriesEngine Maintenance MaintenanceRoutine and Periodic Maintenance Engine AdjustmentsFigure D.3 Clean Cooling System Clean AIR Filter PRE-CLEANERTable D.2 Engine Maintenance Parts Part Part NumberGENERATOR/WELDER Maintenance Figure D.6. Brush Removal and ReplacementFigure D.7. Major Component Locations Symptoms TroubleshootingPossible Areas Generator POWER, Always Not RUN Engine Without AN Diagrams Wiring Diagram Power ARCDimension Print Need Welding Training? How To Read Shop DrawingsNew Lessons in Arc Welding Basic CoursePrecaucion Warnung
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