In the past, CAST IRON has always been difficult to be repaired for all maintenance men. Typically it required:
- heating slowly the pieces in a big oven or with external flames.
- welding with ordinary cast iron electrodes.
- cooling slowly the pieces in the oven.
- and hope that the repaired cast iron does not break again, but it happened often.
Most welders even don’t attempt to weld cast iron due to the low probability of success of these repairs. Breaks and cracks that occur after welding are basically due to:
- Base metal overheating, generated by ordinary cast iron electrodes, which during normal cooling lead to a formation of very hard areas (iron carbides) and therefore fragile, and contractions that cause cracking.
- Low elongation of normal cast iron electrodes, not enough to compensate the contractions which occur during cooling, causing a cracking of the welding itself;
- Porosity caused by dirty (oil, grease, paint and other contaminants) present in the cast iron to be repaired.
Fortunately, times have changed!
Electrodes for CAST IRON
Malloy has developed a series of electrodes technologically advanced for COLD WELDING to easily and reliably repair all cast iron:
MALLOY 771, MALLOY 772 are special electrodes for cold-welding of cast iron. Their features are EASY OF APPLICATION, VERY HIGH ELONGATION, and LOW AMPERAGE, that means no overheating! They also provide welds completely machinable, and possesses special elements in the coating able to eliminate the harmful effects caused by grease, oil and other chemicals contaminants. MALLOY 771, besides welding all cast iron, it is able to weld cast iron to steel. MALLOY 772 has a NOT CONDUCTIVE coating that doesn’t side arc if touching base metal, allowing to access even restricted areas.
With these MALLOY special electrodes you can easily and safely repair any piece of cast iron, without having to dismantle and discard it or sending to a costly external workshops for repairing.
This means SAVE TIME and MONEY!