Test your basic knowledge |

Gas Metal Arc Welding

Instructions:

Answer 50 questions in 15 minutes.
If you are not ready to take this test, you can study here.
Match each statement with the correct term.
Don't refresh. All questions and answers are randomly picked and ordered every time you load a test.

This is a study tool. The 3 wrong answers for each question are randomly chosen from answers to other questions. So, you might find at times the answers obvious, but you will see it re-enforces your understanding as you take the test each time.

1. What wire are knurled drive rolls most commonly used on?
Pressure vessels and the piping industry
Puddle fluidity
Motor driven generators - Transformer rectifiers - and Inverter designs
Flux cored wires

2. What is an advantage of pulsed arc transfer with GMAW?
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
Aluminum wire
1/4 inch to 1/2 inch
Push type: Wire is fed by a set of drive rolls located in the wire feed unit - Pull type: Drive rolls mounted in the gun itself - Push- pull type: Combination of the two

3. What output on the welding machine is used to rate the duty cycle?
Pressure - The rate of flow of a shielding gas
Higher 26 to 35 arc volts
Minutes of elapsed time continually run (out of 10 minutes)
If you dont know this check your phone

4. What is another term for electrode holders for GMAW?
Speed of the feed motor and - starting / stopping electrode feed
Duty cycle
Guns
Push type: Wire is fed by a set of drive rolls located in the wire feed unit - Pull type: Drive rolls mounted in the gun itself - Push- pull type: Combination of the two

5. In the GMAW process what does amperage control?
Compressed gas cylinder - Liquid filled cylinder - or a Liquid bulk system
Short- circuiting transfer - Globular transfer - Spray transfer
Penetration and burn - off rate of the electrode
Aluminum wire

6. List the basic equipment requirements for the GMAW process
Controls the rate of flow of a shielding gas to the gun nozzle
Guns
If you dont know this check your phone
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground

7. What is the effect of too much slope?
Guns
Duty cycle
Insufficient current to melt the wire off cleanly
Minutes of elapsed time continually run (out of 10 minutes)

8. Give a brief description of the GMAW process
If you dont know this check your phone
Welding process that joins metals by heating them with an electric arc
Cause flaking - which can clog the liner and contact tube
Spatter problems and poor weld appearance

9. What 2 controls are found on a GMAW set- up?
Push type: Wire is fed by a set of drive rolls located in the wire feed unit - Pull type: Drive rolls mounted in the gun itself - Push- pull type: Combination of the two
Wire feed speed - Voltage control
By there current carrying capacity
Voltage is the force that overcomes resistance to allow amperage flow

10. What effect does increasing and decreasing the inductance have on the weld?
Duty cycle
These terms are quite restrictive and often technically incorrect
Pressure vessels and the piping industry
Increasing inductance increases puddle fluidity - improves penatration - makes the bead flatter and smoother - and reduces spatter. To much inductance though will create erratic starts

11. What does the term GMAW identify?
Push type: Wire is fed by a set of drive rolls located in the wire feed unit - Pull type: Drive rolls mounted in the gun itself - Push- pull type: Combination of the two
Increasing inductance increases puddle fluidity - improves penatration - makes the bead flatter and smoother - and reduces spatter. To much inductance though will create erratic starts
Gas metal arc welding
To prevent leakage - Carbon Dioxide (CO2)

12. List several industries that would use GMAW
Pressure vessels and the piping industry
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground
Welding process that joins metals by heating them with an electric arc
85%

13. What happens when the electrode extension is increased?
The resistace to electrical current flow increases with it. Causing the electrode to heat
Pressure vessels and the piping industry
Aluminum wire
Minimum distortion due to low heat input

14. What 2 organizations designate specifications for GMAW wires?
Guns
Higher 26 to 35 arc volts
The Arc voltage
AWS and CSA

15. What processes are constant current (CC) power sources designed to be used with?
National Electrical Manufactures Association
SMAW - GTAW
Increasing inductance increases puddle fluidity - improves penatration - makes the bead flatter and smoother - and reduces spatter. To much inductance though will create erratic starts
These terms are quite restrictive and often technically incorrect

16. What current and polarity is generally used with GMAW?
To prevent drawing of liquid CO2 (Carbon Dioxide)
Gas metal arc welding
DCEP (Direct Current Electrode Positive) Reverse Polarity
Generally not as accurate

17. What type of power source is used with a constant speed wire feeder?
To limit the short circuiting current so that spatter is reduced
Wire feeds smoothly (yet will slip should a problem occur in the gun)
To prevent drawing of liquid CO2 (Carbon Dioxide)
Constant voltage (CV)

18. Why is globular transfer generally avoided with GMAW?
12 to 22 arc volts
When the filler wire is in direct contract with the base metal
Cause flaking - which can clog the liner and contact tube
Spatter problems and poor weld appearance

19. What is the minimum % value of argon that must be present to use the spray transfer method of GMAW?
20 to 200 times per second
DCEP (Direct Current Electrode Positive) Reverse Polarity
85%
Wire feed speed

20. Draw a typical volt amp curve for a machine that is designed for GMAW
National Electrical Manufactures Association
SMAW - GTAW
...
If you dont know this check your phone

21. What is the purpose of the shielding gas used in GMAW?
By there current carrying capacity
1/4 inch to 1/2 inch
Shielding the molten weld metal from atmospheric contamination
Welding Current - Filler wire diameter - arc length - type of shielding - position of the weld

22. What would be an indication that the drive roll pressure is adjusted correctly?
Pressure vessels and the piping industry
Wire feeds smoothly (yet will slip should a problem occur in the gun)
Electricaly operated valves that control the flow of shielding gas to the weld zone. The control switch located on the gun
Welding process that joins metals by heating them with an electric arc

23. Why is a line heater required when using GMAW?
Speed of the feed motor and - starting / stopping electrode feed
Dry ice can form within the flow control openings and cause blockage of shielding gas
V groove or U groove
Minimum distortion due to low heat input

24. What is the maximum distance that hard wire can be successfully pushed?
To prevent drawing of liquid CO2 (Carbon Dioxide)
To limit the short circuiting current so that spatter is reduced
15 feet (4.5 meters)
Gives arc voltage values to the control system of the feeder

25. What term is used to describe when the workpiece is hooked to the negative pole on the power source?
(DCEP) Direct Current Electrode Positive or Reverse polarity
If you dont know this check your phone
Pressure - The rate of flow of a shielding gas
Minimum distortion due to low heat input

26. What is the purpose of the pick- up lead on a voltage sensing wire feeder?
Gives arc voltage values to the control system of the feeder
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
Pressure vessels and the piping industry
The negative side of a welding unit

27. List the three methods of metal transfer with GMAW
Puddle fluidity
Short- circuiting transfer - Globular transfer - Spray transfer
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground
The resistace to electrical current flow increases with it. Causing the electrode to heat

28. What does the wire feeder control?
Minutes of elapsed time continually run (out of 10 minutes)
Dry ice can form within the flow control openings and cause blockage of shielding gas
Duty cycle
Speed of the feed motor and - starting / stopping electrode feed

29. With straight polarity where is 2/3 of the arc energy?
The negative side of a welding unit
Voltage is the force that overcomes resistance to allow amperage flow
Pressure vessels and the piping industry
Pressure - The rate of flow of a shielding gas

30. What controls the wire speed on a voltage sensing wire feeder?
Compressed gas cylinder - Liquid filled cylinder - or a Liquid bulk system
The Arc voltage
Higher 26 to 35 arc volts
National Electrical Manufactures Association

31. A 10 minute cycle of welding time vs cooling time a given machine can handle.
To limit the short circuiting current so that spatter is reduced
Duty cycle
Generally not as accurate
Spatter problems and poor weld appearance

32. What is the recommended electrode stick- out for .035 solid wire?
Spatter problems and poor weld appearance
Guns
If you dont know this check your phone
1/4 inch to 1/2 inch

33. What is the preferred drive roll design for solid wires?
5.8 to 12.5 L/min
V groove or U groove
Pressure - The rate of flow of a shielding gas
Increasing inductance increases puddle fluidity - improves penatration - makes the bead flatter and smoother - and reduces spatter. To much inductance though will create erratic starts

34. When using flat drive rolls with too much pressure on copper coated solid wires what problem could take place?
Cause flaking - which can clog the liner and contact tube
Electricaly operated valves that control the flow of shielding gas to the weld zone. The control switch located on the gun
Dry ice can form within the flow control openings and cause blockage of shielding gas
Generally not as accurate

35. What does the abbreviation NEMA stand for?
Wire feeds smoothly (yet will slip should a problem occur in the gun)
The negative side of a welding unit
National Electrical Manufactures Association
Minimum distortion due to low heat input

36. List 3 wire drive systems and give a short description of each
SMAW - GTAW
Push type: Wire is fed by a set of drive rolls located in the wire feed unit - Pull type: Drive rolls mounted in the gun itself - Push- pull type: Combination of the two
Welding process that joins metals by heating them with an electric arc
Wire feeds smoothly (yet will slip should a problem occur in the gun)

37. Is the arc voltage for spray transfer higher or lower than that used for short circuit transfer?
Higher 26 to 35 arc volts
These terms are quite restrictive and often technically incorrect
85%
Minutes of elapsed time continually run (out of 10 minutes)

38. What does voltage do in an electrical circuit?
National Electrical Manufactures Association
20 to 200 times per second
Gas metal arc welding
Voltage is the force that overcomes resistance to allow amperage flow

39. Why must CO2 cylinders be used in the vertical position?
15 feet (4.5 meters)
To prevent drawing of liquid CO2 (Carbon Dioxide)
...
Duty cycle

40. What type of power source is commonly used with a voltage sensing wire feeder?
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
Constant voltage (CV)
Constant current (CC)
AWS and CSA

41. What controls amperage when using GMAW?
Wire feed speed
Penetration and burn - off rate of the electrode
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground
Constant voltage (CV)

42. What is the purpose of a regulator and what does it indicate on its gauges?
Compressed gas cylinder - Liquid filled cylinder - or a Liquid bulk system
AWS and CSA
To limit the short circuiting current so that spatter is reduced
Reducing the gas source pressure to a constant working pressure

43. What is the required arc voltage used for short circuit transfer?
12 to 22 arc volts
Controls the rate of flow of a shielding gas to the gun nozzle
These terms are quite restrictive and often technically incorrect
Constant- speed wire feeders and Voltage- sennsing wire feeders

44. What does a flowmeter do and what does it measure?
Constant- speed wire feeders and Voltage- sennsing wire feeders
The resistace to electrical current flow increases with it. Causing the electrode to heat
Controls the rate of flow of a shielding gas to the gun nozzle
Aluminum wire

45. What is the key advantage of short circuiting transfer?
85%
Minimum distortion due to low heat input
Penetration and burn - off rate of the electrode
The time rate of response for the current rise and fall

46. What does inductance control?
Penetration and burn - off rate of the electrode
20 to 200 times per second
15 feet (4.5 meters)
The time rate of response for the current rise and fall

47. A machine with a 70% duty cycle can run at its max for 7 minutes with a cooling cycle of only _ minutes.
3
Guns
Welding process that joins metals by heating them with an electric arc
If you dont know this check your phone

48. Why is the term GMAW preferred over MIG or MAG?
Dry ice can form within the flow control openings and cause blockage of shielding gas
These terms are quite restrictive and often technically incorrect
V groove or U groove
Motor driven generators - Transformer rectifiers - and Inverter designs

49. How are GMAW guns rated?
Pressure vessels and the piping industry
Minutes of elapsed time continually run (out of 10 minutes)
By there current carrying capacity
...

50. What is the disadvantage of the gauge preset type of regulator/flowmeter?
The time rate of response for the current rise and fall
Generally not as accurate
V groove or U groove
By there current carrying capacity

Test your basic knowledge |

Gas Metal Arc Welding

Top Scores

Link to This Test

Related Subjects