"CWI Practice Exam" Questions and
Answers Verified by Experts
ARC Welding Energy Source Correct Answ_Heat generated by electric arc
Advantages of ARC Welding Correct Answ_Low start up cost, profitability, outdoor use, all
position welding, variety of materials, mechanical properties
Limitations of ARC Welding Correct Answ_low efficiency (65%), operating factor, splatter,
operator skill, restarts, amperage limit, slag
Ideal Amperage for ARC Welding Correct Answ_80-90 amps
Gas Welding Set Up Procedure Correct Answ_1. make sure main valves are off and regulator
pressure adjusting screws are backed out with no pressure readings on gauge
2. ensure torch valves are off
3. stand to side and slowly turn on oxygen cylinder valve. once pressure reads on gauge open
valve all the way and backseat it.
4. stand to side and slowly turn on acetylene (1/2-3/4 turn) or slightly more, get a good reading
,5. set pressure on each regulator (oxy 7-10) (acetylene 7-10)
6. purge each hose individually by opening valves for a few seconds
7. light torch by opening acetylene valve (1/8-1/4 turn) and using torch strike
8. open acetylene torch valve until smoke goes away and flame isn't jumping
9. open oxygen torch valve until inner cone is defined
Gas Welding Shut Down Correct Answ_1. shut off acetylene and hen oxygen valves
2. open up acetylene and oxygen so no pressure read (left)
3. bleed acetylene and oxygen torch lines
4. tighten gauges so they are shut (right)
Gas Welding Eye Protection Correct Answ_requires safety glasses and welding goggles with
a number 4-6 lense
Base Metal Correct Answ_metal to be welded
Fusion Welding Correct Answ_process that joins metals by heating them to a melting point
and allowing them to fuse or flow together; melting, no filler
,Penetration Correct Answ_distance from the original surface of the base metal to that depth
at which fusion stops
Brazing Correct Answ_joins two pieces of metal; similar to fusion but base metal is not
welded; no melting metal, bronze filler
TIG Welding Correct Answ_Tungsten inert gas, higher melting point electrode, shielding gas
is argon or helium
Metals used in TIG Welding Correct Answ_magnesium, aluminum, steel, stainless steel,
brass, alloys, silver, cast iron, copper
Advantages of TIG Welding Correct Answ_easier, good on non-ferris metals
(aluminum/stainless)
TIG Procedural Considerations Correct Answ_Stick out (1/8 to 1/4 in), Arc Length (diameter
of electrode), Angle (15)
, 3 Types of Welding Correct Answ_ARC, Gas, Resistance
Polarity Correct Answ_flow of electrons, electrode to metal or metal to electrode
MIG Welding Correct Answ_metallic inert gas, uses argon and CO2, DC reverse polarity
Advantages of MIG Correct Answ_faster, stronger, easier, better penetration, cleaner, less
distortion
MIG Procedural Considerations Correct Answ_stick out (1/4 to 3/8 in), speed, amperage,
wire speed
6013 electrode Correct Answ_electrode used on thin metal, shallow penetration, easy to use
6011 electrode Correct Answ_electrode with better penetration and can be used on rusty
metal
6010 Correct Answ_most commonly used electrode
Answers Verified by Experts
ARC Welding Energy Source Correct Answ_Heat generated by electric arc
Advantages of ARC Welding Correct Answ_Low start up cost, profitability, outdoor use, all
position welding, variety of materials, mechanical properties
Limitations of ARC Welding Correct Answ_low efficiency (65%), operating factor, splatter,
operator skill, restarts, amperage limit, slag
Ideal Amperage for ARC Welding Correct Answ_80-90 amps
Gas Welding Set Up Procedure Correct Answ_1. make sure main valves are off and regulator
pressure adjusting screws are backed out with no pressure readings on gauge
2. ensure torch valves are off
3. stand to side and slowly turn on oxygen cylinder valve. once pressure reads on gauge open
valve all the way and backseat it.
4. stand to side and slowly turn on acetylene (1/2-3/4 turn) or slightly more, get a good reading
,5. set pressure on each regulator (oxy 7-10) (acetylene 7-10)
6. purge each hose individually by opening valves for a few seconds
7. light torch by opening acetylene valve (1/8-1/4 turn) and using torch strike
8. open acetylene torch valve until smoke goes away and flame isn't jumping
9. open oxygen torch valve until inner cone is defined
Gas Welding Shut Down Correct Answ_1. shut off acetylene and hen oxygen valves
2. open up acetylene and oxygen so no pressure read (left)
3. bleed acetylene and oxygen torch lines
4. tighten gauges so they are shut (right)
Gas Welding Eye Protection Correct Answ_requires safety glasses and welding goggles with
a number 4-6 lense
Base Metal Correct Answ_metal to be welded
Fusion Welding Correct Answ_process that joins metals by heating them to a melting point
and allowing them to fuse or flow together; melting, no filler
,Penetration Correct Answ_distance from the original surface of the base metal to that depth
at which fusion stops
Brazing Correct Answ_joins two pieces of metal; similar to fusion but base metal is not
welded; no melting metal, bronze filler
TIG Welding Correct Answ_Tungsten inert gas, higher melting point electrode, shielding gas
is argon or helium
Metals used in TIG Welding Correct Answ_magnesium, aluminum, steel, stainless steel,
brass, alloys, silver, cast iron, copper
Advantages of TIG Welding Correct Answ_easier, good on non-ferris metals
(aluminum/stainless)
TIG Procedural Considerations Correct Answ_Stick out (1/8 to 1/4 in), Arc Length (diameter
of electrode), Angle (15)
, 3 Types of Welding Correct Answ_ARC, Gas, Resistance
Polarity Correct Answ_flow of electrons, electrode to metal or metal to electrode
MIG Welding Correct Answ_metallic inert gas, uses argon and CO2, DC reverse polarity
Advantages of MIG Correct Answ_faster, stronger, easier, better penetration, cleaner, less
distortion
MIG Procedural Considerations Correct Answ_stick out (1/4 to 3/8 in), speed, amperage,
wire speed
6013 electrode Correct Answ_electrode used on thin metal, shallow penetration, easy to use
6011 electrode Correct Answ_electrode with better penetration and can be used on rusty
metal
6010 Correct Answ_most commonly used electrode
