Lyles 1st Year Review

Question 1

What is C2H2

Answer 1

Acetylene

Question 2

What is C2H2’s critical pressure
a) 20psi
b) 28psi
c) 30psi
d) 38psi

Answer 2

b) 28psi

Question 3

Max safe working pressure (MSWP) of C2H2?
a) 5psi
b) 10psi
c) 15psi
d) 20psi

Answer 3

c) 15psi

Question 4

C2H2 should not be drawn off more than _____ of its capacity per hour or emptied in less than ____ hours.
a) 1/5 , 5
b) 1/6, 6
c) 1/7, 7
d) 1/8, 8

Answer 4

c) 1/7, 7

Question 5

O2 hoses are _______ and have ______ hand threads.
a) red, right hand
b) green, right hand
c) red, left hand
d) green, left hand

Answer 5

b) green, right hand

Question 6

C2H2 hoses are ______ and have ______ threads.
a) red, right hand
b) green, right hand
c) red, left hand
d) green, left hand

Answer 6

c) red, left hand

Question 7

What regulator malfunction occurs when the valve on the high pressure side does not seat properly & gas leaks past the seat; raising the pressure above normal.
a) backfire
b) burn back
c) flash back
d) creep

Answer 7

d) creep
This can blow off the relief valve or rupture the bourdon tube in low pressure gauge.

Question 8

What metal should never be used on oxy-accetylene fittings?
a) titanium
b) copper
c) red bras
d) both b& c

Answer 8

d) both b& c
Red Brass & Copper should never be used on an oxy-acetylene set up

Question 9

There are two different typed of welding tips.
Match the names with the descriptions
Swedge & straight,
The _____ tip produces a thin pointed type flame.
The _____ bore type produces a bulbous type flame.

Answer 9

The swedge tip produces a thin pointed type flame.
The straight bore type produces a bulbous type flame

Question 10

Name the 3 types of flames

Answer 10

Neutral
Carbonizing (reducing, carburizing)
Oxidizing

Question 11

What is a backfire?

Answer 11

A backfire is when the flame backs up into the tip and re-establishes itself with a loud bang or popping sound.

Question 12

Name 3 causes of backfire

Answer 12

• too little of gas speed
• obstruction of gas flow
• loose or faulty seat connection
• dirty tip
• a hot tip

Question 13

What is this a description of?
The speed at which a flame will travel in a pre-mixed gas

Answer 13

flame of propagation

Question 14

How fast will C2H2 burn with O2?
a) 10-17 feet per second
b) 17 - 25 feet per second
c) 15 - 25 feet per second
d) 25 - 29 feet per second

Answer 14

b) 17 - 25 feet per second

Question 15

When referring to the molten metal left on the bottom of a plasma cut what is the name of the left over molten metal?

Answer 15

Dross

Question 16

When referring to the molten metal left on the bottom of an oxyacetylene cut what is the name of the left over molten metal?

Answer 16

Slag

Question 17

What is another name for a standard torch?

Answer 17

heavy duty torch

Question 18

What are the 3 torch type systems?

Answer 18

heavy duty/standard
machine
combination

Question 19

What are the 3 machine control systems

Answer 19

manual and machine tracer
magnetic tracer
electric tracer - CNC

Question 20

What are the 3 cutting methods when using a cutting torch?

Answer 20

across, push, pull

Question 21

What are the 3 methods of prepping material for a cut?

Answer 21

Chiseled (nick)
Drill
Bead of arc weld