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WIRE WELDING

Transverse angle will normally be 90° on a flat workpiece, and 45° for fillet welds. When multiple passes are used, the transverse angle is increased or decreased to place the deposit correctly in the joint.

Weaving

To obtain a wider deposit than obtainable with a straight welding pattern, the torch may be moved along the groove in a side to side movement (weaving). When this technique is used the side to side movement must be stopped shortly at each side to ensure sufficient deposit at the sides of the weld. Weaving in a continuous movement may easily result in insufficient deposit and undercut, which will weaken the joint considerably.

penetration depth and weld pool size. This may be done by increasing travel speed and/or stickout the last 3-5 cm of the weld, and releasing the torch switch immediately when the stop point is reached. Keep the torch in position over the weld until gas flow stops, in order to protect the deposit until the metal has solidified.

Arc starting and stopping When starting the arc on a cold workpiece, penetration may be insufficient to provide sufficient binding for a short moment before the weld pool is properly established. To avoid a weakness in the joint the arc may either be started on a plate attached to the workpiece at the beginning of the joint, or the welder may increase the heat input. This may be done by starting the arc approximately 2-3 cm after the beginning of the weld, moving the arc quickly back to the actual starting point and continue welding over the slightly preheated area. Reduced electrode stickout for the first 1-2 cm will further improve heat input. When finishing the weld the heat input should be reduced to reduce

4.03

Torch angles in vertical welding, backhand technique

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