What is the specific gravity for propane vapor?
1.55.
When using oxygen from a cylinder, you should open the valve ______
Fully
The most suitable flame to use when heating with oxyacetylene equipment is ________
Neutral flame
When you purge oxyacetylene equipment prior to lighting the torch, you adjust the acetylene regulator _____PSI
5
Why can’t you store acetylene on concrete?
Acetylene reacts with the lime in concrete, leaving it on cement can allow acetylene to seep into concrete.
These compounds together can explode from vibration or friction
What do you keep in mind when opening acetylene valve?
Left hand threads (counterclockwise)
Only open 1/2 to 1 full turn
Never use above 15PSI
What is a neutral flame?
Neutral flame is used for heating and cutting
What is a carburizing flame?
Flame with excess acetylene
(Feather)
What is an oxidizing flame?
Flame with excess oxygen
(Flame is short and makes hissing noise)
What is a backfire?
Usually caused when touching tip to work, creates pop noise and flame goes out
What is a flashback?
When the flame burns backwards into the torch (flame speed exceeds gas flow speed)
Happens because of incorrect gas pressure, dirty tip, overheating
What pressure does acetylene become unstable at?
15PSI
What is the critical point for acetylene?
28PSI
What are acetylene’s characteristics?
Lighter than error
Colourless but strong odour
cylinder has acetone in it
