B-15

OPERATION

B-15

 

 

 

Now weld the two plates together. Weld from left to right (if right-handed). Point the electrode down in he gap between the two plates, keeping the electrodes slightly tilted in the direction of travel.

20°

end view

90°

side view

Watch the molten metal to be sure it distributes itself evenly on both edges and in between the plates.

Penetration

Unless a weld penetrates close to 100%, a butt weld will be weaker than the material welded together.

1/2"

Poor (12mm)1/4" (6mm)

1/4"

(6mm)

In this example, the total weld is only 1/2 the thickness of the material; thus, the weld is only approximately half as strong as the metal.

Good

Fillet Welds

When welding fillet welds, it is very important to hold the electrode at a 45° angle between the two sides, or the metal will not distribute itself evenly.

To make it easier to get the 45° angle, it is best to put the electrode in the holder at a 45° angle, as shown.

45°

45°

Multiple Pass Welds

Make multiple pass horizontal fillets as shown in the sketch. Put the first bead in the corner with fairly high current. Hold the electrode angle needed to deposit the filler beads as shown putting the final bead against the vertical plate.

 

4

 

2

1

3

2

 

 

1

 

 

Welding in the Vertical Position

In this example, the joint has been flame beveled or ground prior to welding so that 100% penetration could be achieved. The weld, if properly made, is as strong or stronger than the original metal.

60°

4

3 2

1

1/8" (3.2mm)

Successive passes must be used to build up butt welds on heavier metal.

Welding in the vertical position can be done either vertical-up or vertical-down. Vertical-up is used whenever a large, strong weld is desired. Vertical-down is used primarily on sheet metal for fast, low penetrating welds.

POWER-ARC 4000

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Lincoln POWER-ARC 4000 manual Penetration, Fillet Welds, Multiple Pass Welds, Welding in the Vertical Position