answered to pass
Deoxidizers in GMAW filler wires play a particularly important role when - correct answer ✔✔CO2
shielding is used
Which filler wire contains high levels of manganese and silicon and is recommended for applications
where bead appearance and low splatter are important - correct answer ✔✔ER480S-5 (ER70S-5)
The primary advantage of a constant voltage power source over a constant current power source for
GMAW is - correct answer ✔✔the self-correcting voltage control
Which of the following occurs when the wire stickout is increased while GMAW with a CV power source?
- correct answer ✔✔decreased penetration
When GMAW with a CV power source, wagon tracks can be minimized by - correct answer ✔✔reducing
the arc voltage/increasing the arc voltage
In GMAW, the pulling technique - correct answer ✔✔produces deeper penetration than the pushing
technique
characteristic of a carbon dioxide shielded arc - correct answer ✔✔good surface cleaning action
The primary function of a voltmeter in the welding circuit of a CV power source is to indicate the -
correct answer ✔✔load voltage
The polarity used for welding aluminum with the GMAW process is - correct answer ✔✔DCEN
Which filler wire contains aluminum, titanium, and zirconium and is often selected for welding rusty or
dirty base materials - correct answer ✔✔ER480S-4 (ER70S-4)
, Wire stickout or extension refers to the distance from the end of the - correct answer ✔✔contact tip to
the base material
Which gases are recommended to minimize spatter when welding mild steel in the short circuit transfer
mode - correct answer ✔✔25% - Ar & 75% He
For short-circuit GMAW, the wire stickout distances generally from - correct answer ✔✔6.4 to 19 mm
(1/4 to 3/4")
In the short circuit transfer, what is the effect of increasing the slope on a CV power source - correct
answer ✔✔minimizes the voltage drop at arc reignition
What is the effect of adding small amounts of CO2 (1%-3%) - correct answer ✔✔improved penetration
at wetting action
When a CV power source has been energized and the gun trigger has been actuated but no arc has been
struck, the voltmeter reading will indicate the - correct answer ✔✔open-circuit voltage
The mode of metal transfer that uses the lowest voltage and current levels is - correct answer ✔✔spray
transfer
When GMAW, spray transfer is only possible if the welding current is - correct answer ✔✔DCEP
With constant voltage power sources, increases in arc length will - correct answer ✔✔decrease voltage
To prevent cold lap when welding a 25mm thick vee-groove butt joint with the GMAW processes -
correct answer ✔✔use a split bead technique to fill the joint OR focus the arc on the centre of the joint
Which shielding gas mixture is used for GMAW in the spray transfer mode on mild steel - correct answer
✔✔98% Ar & 2% O2