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NICKEL-333 N

Unitor NICKEL-333 N is a special electrode for cold welding of oily cast iron.

2–3 cm

Prepare the damaged area in the following manner: Use a crack detector to determine the actual length of the crack or fracture. Drill a hole at the end of the crack, using a 3 mm drill, to prevent further fracturing during welding. AC or DC negative or positive polarity may be used. Use a fairly short arc. Hold the electrode almost at a right angle to the work and weld in short beads of 2–3 cm at a time. When a bead is completed, it must be peened to counteract shrinkage. Start from the crater and work backwards to the starting point.

Weld in short beads.

Drill a 3 mm hole at the end of the crack.

Allow the weld to cool before continuing. A general rule is that the welding area should be hand warm before welding the next bead of 2–3 cm (cold welding).

3.01

When repairing a crack which has not split the workpiece into two separate parts, always weld from the outer ends of the crack and inwards. The thickness of the material is the deciding factor in choosing between NICKEL-333 N or NIFE-334 N. NICKEL333 N is for use on thinner materials, or as a first bead on oily cast iron, to be followed by beads welded with NIFE-334 N. NIFE-334 N is used for multibead welding on heavy gauge materials.

After welding, the bead’s tendency to shrink can cause cracking. Peening the bead counteracts the shrinkage forces.

Start welding at the end of the crack and work inwards.

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