Spray Transfer welding
The spray transfer is named for the spray of tiny molten droplets across the arc, not unlike the spray coming out of a garden hose when the opening is restricted. A spray transfer is usually smaller than the diameter of the wire and uses relatively high voltage and wire feed speeds or amperage. Unlike the short circuit transfer, once the arc is established, the arc is “on” at all times. There is very little spatter with the spray transfer mode and it is usually used on thicker metals in flat and horizontal positions. The spray transfer is normally found in solid MIG wires and metal cored wires with a high ratio of Argon in the shielding gas, usually above 90%. A partial or semi-spray transfer is found in gas shielded flux cored wires when an Argon CO2 shielding gas is used.
Pulse Spray Transfer welding
For this variation of spray transfer, the welding machine “pulses” or cycles the output between high peak currents and low background currents. This allows the weld pool to cool slightly in the background cycle, making it slightly different than a true spray transfer. This advantage allows for welding in all positions on either thin or heavy plate material. Solid MIG wires and Gas Shielded Metal Cored wires show the greatest advantage when the pulse mode of transfer is used.
advantages of pulse welding:
- It can weld a variety of metals.
- It has good penetration.
- It can weld a wide range of thicknesses.
- It provides good fusion at the toes of the weld.
- It can be used to weld in all positions.
- It reduces the number of ASME and AWS certifications require