Chapter 20

Question 1

How do you Depressurize?

Answer 1

1. Close both cylinder valves.
2. Open the torch acetylene valve to depressurize the acetylene gauges and hose.
3. Close the torch acetylene valve.
4. Open the torch oxygen valve to depressurize the oxygen gauges and hose.
5. Close the torch oxygen valve.
6. Turn out the adjusting screws on the oxygen and acetylene regulator valves.

Question 2

How do you set a carburizing flame?

Answer 2

Open the torch oxygen valve until a feathered cone exists in the flame.

o Three flame zones are present. They are the inner cone, the acetylene feather, and the outer envelope.

Question 3

How do you set a neutral flame?

Answer 3

Open the torch oxygen valve until the acetylene feather disappears and only the inner cone and outer envelope exist.

o When the feathery edges of the inner cone disappear, a neutral flame is present.

Question 4

How do you set an oxidizing flame?

Answer 4

Open the torch oxygen valve beyond a neutral flame to a point where the flame is pale blue.

o The inner cone will be shorter, will become slightly pointed, and the flame will be noisier than the neutral flame.