AWS Welder Material & Equipment Handling 2 — Questions and Answers
Question 1: When storing compressed gas cylinders in a shop, how must full and empty cylinders be stored?
- Together to save space
- Separately and clearly labeled (Correct answer)
- Empty cylinders can be stored on their side
- Full cylinders must be stored horizontally
Correct answer: Separately and clearly labeled
Full and empty cylinders must be stored separately and clearly labeled to prevent accidental use of a depleted cylinder or confusion during emergencies.
Question 2: Which electrode classification suffix indicates that the electrode has a low-hydrogen coating?
- EXX10
- EXX13
- EXX18 (Correct answer)
- EXX11
Correct answer: EXX18
The EXX18 suffix designates a low-hydrogen iron powder electrode, which requires storage in a rod oven to maintain its moisture-free coating.
Question 3: What is the primary purpose of a wire feed unit's drive roll tension in GMAW?
- To increase wire travel speed
- To control shielding gas flow
- To ensure consistent wire feeding without slipping or birdnesting (Correct answer)
- To regulate voltage output
Correct answer: To ensure consistent wire feeding without slipping or birdnesting
Proper drive roll tension ensures the wire feeds smoothly and consistently without slipping or forming a bird's nest at the wire feeder.
Question 4: Which type of base metal preparation is required before welding galvanized steel?
- Preheat to 600°F before welding
- Remove the zinc coating from the weld zone (Correct answer)
- Apply extra shielding gas to neutralize zinc fumes
- Increase amperage by 50% to burn off the coating
Correct answer: Remove the zinc coating from the weld zone
The zinc coating must be removed from the weld zone because it produces toxic zinc oxide fumes and causes porosity in the weld.
Question 5: A welder notices the MIG gun liner is kinked. What is the correct action?
- Straighten the liner with pliers and continue welding
- Replace the liner to restore smooth wire feeding (Correct answer)
- Increase drive roll tension to overcome the kink
- Reduce wire speed to compensate
Correct answer: Replace the liner to restore smooth wire feeding
A kinked liner must be replaced because it disrupts consistent wire feeding and cannot be reliably straightened to original condition.
Question 6: What is the correct procedure when a gas cylinder valve is difficult to open?
- Use a pipe wrench for extra leverage
- Strike the valve with a hammer to loosen it
- Contact the supplier — never force a stuck valve (Correct answer)
- Apply penetrating oil to the valve threads
Correct answer: Contact the supplier — never force a stuck valve
A stuck cylinder valve should never be forced; the cylinder must be returned to the supplier as a faulty valve can be dangerous.
Question 7: What does the designation ER70S-6 indicate about a GMAW wire electrode?
- It is flux-cored and requires no shielding gas
- It is a solid wire with 70,000 psi tensile strength and high deoxidizer content (Correct answer)
- It requires 100% CO2 shielding gas only
- It is designed exclusively for stainless steel
Correct answer: It is a solid wire with 70,000 psi tensile strength and high deoxidizer content
ER70S-6 indicates a solid electrode rod with minimum 70,000 psi tensile strength and high levels of silicon and manganese deoxidizers for welding over mill scale.
AWS Welder Material & Equipment Handling 2
When storing compressed gas cylinders in a shop, how must full and empty cylinders be stored?