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SOLUTIONS: Cast Iron

Sometimes more than one short run can be done at a time, but only when the length to be welded is considerable, and the beads can be

spaced well away from each other to prevent heat build-up. This technique is called skip-welding and speeds up the work considerably:

Repairing crack with free end

2.07

Start welding at tied end, then backstep towards free end.

Repairing crack with tied ends Put the two first beads (2 - 3 cm each) starting from the hole drilled at each end of the crack. Then weld alternatively from each end of the crack, using the backstep technique. Repair of separated parts Starting from one edge, use the backstep technique across the part to the opposite edge.

Parts subject to high stresses To strengthen the transition zone transverse grooves may be cut in the sides of the welding groove, using chamfering electrode Unitor CH-2 382. First fill up these grooves with the electrode selected for the first layer, and then cover the entire surface of the groove with a deposit of the same electrode, without peening. Then proceed to fill up the groove. Remember the build-up should always be done with Unitor NIFE-334N

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Cut transverse grooves in the sides. Fill them first, then cover the entire surface before proceeding to build up and join.