Features and Procedures to Weld the Cast Iron
Before welding the cast iron alloys, it is important to know about the cast iron. A cast iron is an alloy of iron, carbon, and silicon, in which the amount of carbon is less than 4.5 percent and more than 1.7 percent. Ductile and malleable irons have good weldability, but the overall weldability of cast iron is low. The welding factors of a cast iron fully depend on the material type, complexity, thickness, casting complexity and need for machinability. It is difficult to weld cast iron, but not impossible. Welding on cast iron involves repairs to castings, not joining casting to other members.
Do you know, what is the most common type of cast iron used worldwide? Gray iron is the most common type of cast iron which has a variety of compositions. There are alloy cast irons which contain small amounts of chromium, nickel, molybdenum, copper, or other elements. The repairs are made in the foundry where the castings are produced and it is also made to repair casting defects that are discovered after the part is machined. The broken cast irons are repaired by welding and the high carbon content causes the carbon to form flakes of graphite. While making the castings, metal iron is poured into a mold and then it is allowed to cool slowly.
Here are the tips on welding cast iron –
Determine the metal first. The type of material is determining the approach to the repair. The only positive identification is a chemical analysis and metallographic check of the structure. Grey cast iron is particularly good for compressive loads such as machine bases. The grey cast iron is having the unique damping properties, the feature that is readily apparent when the metal is struck.
Prepare the part now. The casting must be prepared assuming the metal is grey cast iron. Further propagation is prevented through a crack ending in solid metal. The joint preparation includes chipping, grinding, air carbon arc gouging or similar techniques. It is also preferable to weld both sides of the joint rather than a single side weld.
Stress on the heat treatment processes. Make sure that you try eliminating activities which cause tensile stress like bending, crimping or shrink fitting. Thermal treatment is helping reduction of the residual stresses. A number of cast irons are made with E Ni-Cl or E NiFe-Cl electrodes without any weld heat treatment.
It is important to weld filler metal. Processes like oxyacetylene, shielded metal arc, gas metal arc welding, and brazing are used to join the cast iron. The most common process is field repair welding with nickel cored (AWS E Ni-Cl) and nickel-iron cored (AWS E NiFe-Cl) electrodes.
These types of metals are used in agriculture equipment, on machine tools, pipe fittings, cast iron pipe, cylinder heads, deep drawing dies, pump housings, automobile engine block, water preps, and repair defects to upgrade or salvage a casting. Cast iron welding alloys are rarely used in structural work except for compression members. It is widely used in construction machinery for counterweights and in other applications for which weight is required.
Do you know, what is the most common type of cast iron used worldwide? Gray iron is the most common type of cast iron which has a variety of compositions. There are alloy cast irons which contain small amounts of chromium, nickel, molybdenum, copper, or other elements. The repairs are made in the foundry where the castings are produced and it is also made to repair casting defects that are discovered after the part is machined. The broken cast irons are repaired by welding and the high carbon content causes the carbon to form flakes of graphite. While making the castings, metal iron is poured into a mold and then it is allowed to cool slowly.
Here are the tips on welding cast iron –
Determine the metal first. The type of material is determining the approach to the repair. The only positive identification is a chemical analysis and metallographic check of the structure. Grey cast iron is particularly good for compressive loads such as machine bases. The grey cast iron is having the unique damping properties, the feature that is readily apparent when the metal is struck.
Prepare the part now. The casting must be prepared assuming the metal is grey cast iron. Further propagation is prevented through a crack ending in solid metal. The joint preparation includes chipping, grinding, air carbon arc gouging or similar techniques. It is also preferable to weld both sides of the joint rather than a single side weld.
Stress on the heat treatment processes. Make sure that you try eliminating activities which cause tensile stress like bending, crimping or shrink fitting. Thermal treatment is helping reduction of the residual stresses. A number of cast irons are made with E Ni-Cl or E NiFe-Cl electrodes without any weld heat treatment.
It is important to weld filler metal. Processes like oxyacetylene, shielded metal arc, gas metal arc welding, and brazing are used to join the cast iron. The most common process is field repair welding with nickel cored (AWS E Ni-Cl) and nickel-iron cored (AWS E NiFe-Cl) electrodes.
These types of metals are used in agriculture equipment, on machine tools, pipe fittings, cast iron pipe, cylinder heads, deep drawing dies, pump housings, automobile engine block, water preps, and repair defects to upgrade or salvage a casting. Cast iron welding alloys are rarely used in structural work except for compression members. It is widely used in construction machinery for counterweights and in other applications for which weight is required.
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