Review Questions - GMAW

Question 1

Which GMAW Transfer mode is the most prone to incomplete fusion?

1. short-curcuit
2. globular
3. spray
4. pulsed

Answer 1

Short-curcuit

Question 2

the required electrode extenion for short-circuit transfer is;

1. 6-12 mm (1/4 - 1/2 in)
2. 10-15 mm (3/8 - 5/8 in)
3. 15-19 mm (5/8 - 3/4 in)
4. 19-25mm (3/4 -1 in)

Answer 2

6-12 mm (1/4 - 1/2 in)

Question 3

the GMAW method that uses low currents and low voltages for all postion welding is:

1. spray transfer
2. globular transfer
3. short-curcuit transfer
4. pulsed arc

Answer 3

short-curcuit transfer

Question 4

When GMA welding, how is the shielding gas controlled?

1. regulator
2. power source
3. flow meter
4. wire feeder

Answer 4

Flow meter

Question 5

A power supply set to constant current mode requires a:

1. voltage-sensing wire feeder
2. constant-speed wire feeder
3. current-sensing wire feeder
4. pulse-sensing wire feeder

Answer 5

voltage-sensing wire feeder

Question 6

The rate at which the process moves along the weld joint is called the:

1. wire feed speed
2. arc travel speed
3. current travel speed
4. heat input speed

Answer 6

arc travel speed

Question 7

GMAW in globular transfer mode:

1. uses higher current and voltage than spray
2. is usually avoided due to spatter
3. requires a pulsed power supply
4. works better with flux injection

Answer 7

is usually avoided due to spatter

Question 8

the distance from the end of the contact tube to the weld pool is:

1. arc length
2. tip-to-work distance
3. requires a pulsed power supply
4. works better with flux injection

Answer 8

tip-to-work distance

Question 9

the GMAW process protects the weld pool through the use of:

1. inert of reactive gases
2. inert shielding gas
3. granular flux
4. reactive slags

Answer 9

inert of reactive gases

Question 10

When welding the first passes of thick groove joints with weld backing:

1. the first pass is done using short-circuit transfer
2. the first pass is done using a drag technique
3. the first pass is done using a push technique
4. the first pass is done using globular transfer

Answer 10

the first pass is done using a drag technique

Question 11

The GMAW method that uses surges of current and voltage for all position welding without spatter is:

1. spray transfer
2. globular transfer
3. short-curcuit trasnfer
4. pulsed spray transfer

Answer 11

pulsed spray transfer

Question 12

which shielding medium is most often used for carbonsteel in short-circuit transfer mode?

1. 75% argon / 25% helium
2. 90% argon / 10% oxygen
3. 75% helium / 25% argon
4. 100% carbon dioxide

Answer 12

100% carbon dioxide

Question 13

A power supply set to constant voltage mode reqires a:

1. voltage-sensing wire feeder
2. constant-speed wire feeder
3. current-sensing wire feeder
4. pulse-sensing wire feeder

Answer 13

constant-speed wire feeder

Question 14

GMAW systems are usually connected as:

1. electrode positive
2. electrode negative
3. electrode alternating
4. electrode pulsing

Answer 14

electrode positive

Question 15

When using the short-curcuit transfer mode:

1. the contact tip extends out of the gas cup
2. high argon gas mixtures must be used
3. knurled drive rolls are most common
4. a long wire stickout is held

Answer 15

the contact tip extends out of the gas cup

Question 16

A wire hang up in the drive rollers is also referred to as?

1. a tangled mess
2. a wire jamb
3. bird nesting or nesting
4. a wire feed malfunction

Answer 16

bird nesting or nesting

Question 17

What is the maximum distance for pushing wire, using a push type drive system?

1. 3 meters (9.8 feet)
2. 4.5 meters (15 feet)
3. 7.62 meters (25 feet)
4. none of the above

Answer 17

4.5 meters (15 feet)

Question 18

Which shielding gas may require an in line heater at high flow rates?

1. argon
2. helium
3. CO2
4. Hydrogen

Answer 18

CO2

Question 19

What do the letters GS mean in the following type of electrode? ER70S-GS

1. grind to sound metal
2. gold/silver added
3. intended for single pass only
4. multi pass welding only

Answer 19

intended for single pass only

Question 20

What does the letter C stand for in the following type of electrode? ER70C-X

1. carbon steel only
2. composite filler metal
3. cast-iron compatible
4. carbon dioxide shielding required

Answer 20

composite filler metal