Galvanneal steel is similar to galvanized steel. The heat from the arc will easily burn off the zinc covering. However, the resultant weld may have a number of difficulties, including high porosity, an unsatisfactory bead look, a lack of fusion, fractures, and heavy spatter. These defects are usually not serious enough to destroy the pipe completely, but they should be considered when specifying welding procedures for this material.
Welding galvaneal steel requires special techniques to avoid burning or melting the zinc coating. The filler metal should be bright so it will cover the zincoated area properly. Preheat the substrate to approximately 500°F (260°C) before beginning the process. This will remove the zinc oxide that would otherwise be formed during cooling after each pass with the welding rod.
The weld should be ground down carefully to remove any excess metal along with the oxides. This will ensure good penetration by the next pass and minimize porosity development in the joint.
Galvannealed steel has many advantages for industrial applications. It can be used instead of plain carbon steel because of its resistance to corrosion. Also, due to its low cost and availability, it's often used for piping that won't see high pressures or temperatures.
Galvanized steel is just steel that has been coated with a thick coating of zinc. In terms of welding, once the zinc coating has been removed and adequate safety precautions have been taken, galvanized steel may be weld just like regular steel. Galvanized steel is more resistant to corrosion than plain old steel, so it can be used in environments where you would otherwise get metal fatigue from constant exposure to moisture and other elements.
In general, if the material you are working with is valid for welding, then it can be welded. The only real restriction is that the material must not contain any substances that could burn or explode during welding (such as gasoline), but other than that, there are no restrictions on what type of materials we can weld together.
As long as you take the proper precautions and follow the instructions in your manual, you should have no problems welding galvanized metal. However, since it is recommended not to weld across gaps of over 1/4 inch, it is important to pay attention to how you are joining these pieces together.
Welding galvanized steel causes the zinc to evaporate near the arc (zinc boils before steel melts). In the air, the zinc oxidizes to a fine white powder. Prolonged exposure to these vapors might result in negative effects that linger for up to 24 hours. Welders are at risk from airborne zinc particles.
Galvanizing is a process where iron or steel is coated with a layer of zinc to prevent corrosion. Galvanized steel can be welded just like uncoated steel, but the welding process must be done carefully so as not to damage the coating. If the coating is damaged during welding repair work will be needed before further processing or use of the material is possible.
Welding galvanized metal produces zinc oxide which needs to be removed from the workplace periodically. It is recommended to wear protective clothing and equipment while working with this material.
The health risks associated with welding galvanized steel include inhalation of zinc particles which can cause lung disease and skin reactions such as dermatitis and eczema. Other hazards include the emission of carbon monoxide, nitrogen oxides, and arsine into the environment due to high temperatures required for welding galvanized steel.
People who work with welding materials should follow safety procedures to avoid accidents. Keep children away from welding areas. Use only certified welding technicians to ensure quality workmanship. Training programs are available through community colleges and vocational schools.