Cast iron consists of an alloy of iron and carbon, and also contains impurities of other elements. Cast iron is conventionally divided into two colors. White cast iron is brittle because the carbon it contains is bound. It cannot be machined or welded. The gray contains carbon in the form of graphite, it has a silvery-gray color and is welded. If you choose the right one for welding cast iron electrodes then this will guarantee the reliability of the deposited surfaces and welds and increase the durability of the structural device.
Cast iron properties
A characteristic feature of cast iron is fragility and low strength, even poor weldability. Often, cast iron has to be welded when repair or refurbishment work is done. For the purpose of welding cast iron, 2 types are used: hot welding and cold welding. Cold welding electrodes are used when equipment needs to be repaired to recreate worn-out parts. Thanks to them, the seam is obtained with the necessary qualities in the form of steel with elements of copper, nickel and iron-nickel alloys.
Types and purpose of welding electrodes
For cold welding and surfacing of cast iron products, no preheating is done. Welding technology is done with small rollers 25-60 mm long with further cooling of each roller at t-60 degrees. It is recommended to hammer each individual roll with a slight hammer blow. Varieties of electrodes:
- TsCh-4 electrodes for welding are advised to be used for repairing non-main structures;
- MNCH-2 surfacing welding electrodes are used for surfacing in industry;
- Surfacing welding electrodes OZCH-3 are used to eliminate small defects in the main structures;
- OZCH-4 surfacing electrodes are recommended to be used for welding with a finishing layer in structures where parts are abraded;
- Surfacing electrodes OZCH-2 Surfacing with such electrodes gives the seam plasticity and can be processed.
These welding electrodes are manufactured in accordance with the specifications of the plant.
