Modes Of Metal Transfer In GMAW, GMAW-P, FCAE and MCAW Flashcards
What volts and welding currents are used for short-circuit, globular, spray and pulsed? What positions can they be used in?
Short-circuit uses low arc voltage and welding currents. Short-circuit can be used in all positions
Globular and spray use higher arc voltage and welding currents. Globular is usually limited to flat and horizontal fillet welds
Pulsed spray transfer, in which the welding amperage rises and falls at extremely fast rate, measured in pulses per second, can be used in more out of position welding.
How many transfers occur every second with short-circuit and what is it used more for and what positions can it be used in?
Every second 20-200 transfers occur. It is used mostly for GMAW on ferrous metals and can weld in all positions.
What are some modified short-circuit metal transfer modes that use microprocessors to make the heat even more precise?
Lincins Electrics STT (Surface Tension Transfer) and Miller Electrics RMD (Regulated Metal Deposit)
What is the rate of droplet transfer using globular? What positions can it be welded in?
20 to 70 per second.
It’s most common with FCAW and can be welded in all positions, particularly with small wire diameter. When used with GMAW and MCAW it is generally only welded in flat and horizontal positions
How does spray transfer work?
It sprays the wire in a line with axis to the electrode at several hundred droplets per second. It has a high deposition rate and for joining materials 3.2mm (1/8 in.) And thicker. It welds in flat and horizontal unless you’re welding copper or aluminum. Spray transfer is generally restricted to GMAW and MCAW. It only occurs with DCEP welding current and either shielding gas containing at least 80% argon.
Explain pulsed spray
It has 2 current levels a background and a “pulsed peak” this allows for welding on lighter gauge metals allows for out of position welding. It has to have an 80% argon shielding gas to be considered spray
