G60 Equipment Inspection and Maintenance 2 — Questions and Answers
Question 1: When should flashback arrestors be installed on a torch system?
- At both the torch and regulator ends of each hose (Correct answer)
- Only at the torch end
- Only at the cylinder regulator end
- They are optional if hoses are short
Correct answer: At both the torch and regulator ends of each hose
Flashback arrestors should be installed at both the torch end and the regulator end of each hose to provide maximum protection against flashback.
Question 2: What is the purpose of purging gas lines before lighting a torch?
- To remove any air or mixed gases from the hoses before ignition (Correct answer)
- To increase the gas pressure in the hose
- To cool down the hose before use
- To test the regulator gauge accuracy
Correct answer: To remove any air or mixed gases from the hoses before ignition
Purging clears air or any mixed gases from hoses and the torch body, preventing a potentially explosive mixture from being ignited at startup.
Question 3: What condition indicates a torch tip needs to be cleaned or replaced?
- A popping or uneven flame (Correct answer)
- A steady blue cone flame
- Normal operating temperature
- Clear gas flow from the orifice
Correct answer: A popping or uneven flame
A popping, irregular, or uneven flame is a sign that the torch tip orifice is dirty or damaged and needs cleaning or replacement.
Question 4: Which tool is approved for cleaning a clogged torch tip orifice?
- A tip cleaner (tip drill) of the correct size (Correct answer)
- A steel wire or nail
- Compressed air blown through the tip
- A knife or sharp blade
Correct answer: A tip cleaner (tip drill) of the correct size
Only an approved tip cleaner (tip drill) of the correct size should be used to clean a torch tip to avoid enlarging or damaging the orifice.
Question 5: What should be done with a cylinder that has a damaged or leaking valve?
- Label it defective, move it outdoors away from ignition sources, and contact the supplier (Correct answer)
- Attempt to tighten the valve stem with pliers
- Cap the cylinder and store it indoors until repair
- Continue using it at reduced pressure
Correct answer: Label it defective, move it outdoors away from ignition sources, and contact the supplier
A cylinder with a damaged or leaking valve must be labeled defective, moved safely outdoors away from ignition sources, and reported to the supplier immediately.
Question 6: How should oxygen cylinder valves be opened?
- Slowly and fully, then backed off a quarter turn (Correct answer)
- Rapidly and fully to maximize flow
- Only halfway to restrict pressure
- Quickly for one second then closed
Correct answer: Slowly and fully, then backed off a quarter turn
Oxygen cylinder valves should be opened slowly and completely, then backed off a quarter turn to prevent the valve from becoming stuck open under high pressure.
G60 Equipment Inspection and Maintenance 2
When should flashback arrestors be installed on a torch system?