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. List several industries that would use GMAW
Minutes of elapsed time continually run (out of 10 minutes)
Pressure vessels and the piping industry
These terms are quite restrictive and often technically incorrect
Flux cored wires

2. What output on the welding machine is used to rate the duty cycle?
Electricaly operated valves that control the flow of shielding gas to the weld zone. The control switch located on the gun
The Arc voltage
Spatter problems and poor weld appearance
Minutes of elapsed time continually run (out of 10 minutes)

3. What is the effect of too much slope?
85%
Aluminum wire
Insufficient current to melt the wire off cleanly
20 to 200 times per second

4. What controls the wire speed on a voltage sensing wire feeder?
The Arc voltage
Duty cycle
3
The resistace to electrical current flow increases with it. Causing the electrode to heat

5. What wire are knurled drive rolls most commonly used on?
85%
5.8 to 12.5 L/min
Flux cored wires
Cause flaking - which can clog the liner and contact tube

6. Is the arc voltage for spray transfer higher or lower than that used for short circuit transfer?
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
If you dont know this check your phone
Wire feed speed - Voltage control
Higher 26 to 35 arc volts

7. How are GMAW guns rated?
By there current carrying capacity
Welding process that joins metals by heating them with an electric arc
Constant- speed wire feeders and Voltage- sennsing wire feeders
Compressed gas cylinder - Liquid filled cylinder - or a Liquid bulk system

8. List the basic equipment requirements for the GMAW process
Shielding the molten weld metal from atmospheric contamination
The negative side of a welding unit
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

9. With straight polarity where is 2/3 of the arc energy?
The negative side of a welding unit
15 feet (4.5 meters)
Electricaly operated valves that control the flow of shielding gas to the weld zone. The control switch located on the gun
(DCEP) Direct Current Electrode Positive or Reverse polarity

10. What processes are constant current (CC) power sources designed to be used with?
SMAW - GTAW
3
Wire feed speed
The time rate of response for the current rise and fall

11. What is the purpose of the shielding gas used in GMAW?
To limit the short circuiting current so that spatter is reduced
Shielding the molten weld metal from atmospheric contamination
Welding process that joins metals by heating them with an electric arc
Speed of the feed motor and - starting / stopping electrode feed

12. Why must CO2 cylinders be used in the vertical position?
To prevent drawing of liquid CO2 (Carbon Dioxide)
Insufficient current to melt the wire off cleanly
85%
Reducing the gas source pressure to a constant working pressure

13. What is the reason glass 'tube' type flowmeters must have the tube mounted truly vertical?
...
Shielding the molten weld metal from atmospheric contamination
15 feet (4.5 meters)
Constant voltage (CV)

14. What is the disadvantage of the gauge preset type of regulator/flowmeter?
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
Generally not as accurate
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

15. Why is the term GMAW preferred over MIG or MAG?
These terms are quite restrictive and often technically incorrect
Voltage is the force that overcomes resistance to allow amperage flow
To prevent leakage - Carbon Dioxide (CO2)
Gas metal arc welding

16. What would be an indication that the drive roll pressure is adjusted correctly?
Wire feeds smoothly (yet will slip should a problem occur in the gun)
Puddle fluidity
Compressed gas cylinder - Liquid filled cylinder - or a Liquid bulk system
The Arc voltage

17. What type of power source is used with a constant speed wire feeder?
85%
The time rate of response for the current rise and fall
The Arc voltage
Constant voltage (CV)

18. What does the wire feeder control?
By there current carrying capacity
Speed of the feed motor and - starting / stopping electrode feed
5.8 to 12.5 L/min
Gas metal arc welding

19. What is the minimum % value of argon that must be present to use the spray transfer method of GMAW?
85%
Pressure vessels and the piping industry
Molten metal is separated from the end of the filler wire by a squeezing force created by a magnetic field
Motor driven generators - Transformer rectifiers - and Inverter designs

20. When using flat drive rolls with too much pressure on copper coated solid wires what problem could take place?
Pressure vessels and the piping industry
15 feet (4.5 meters)
Cause flaking - which can clog the liner and contact tube
Aluminum wire

21. What does voltage do in an electrical circuit?
3
Gives arc voltage values to the control system of the feeder
Voltage is the force that overcomes resistance to allow amperage flow
Compressed gas cylinder - Liquid filled cylinder - or a Liquid bulk system

22. What power sources are used with the GMAW Process?
Controls the rate of flow of a shielding gas to the gun nozzle
Wire feeds smoothly (yet will slip should a problem occur in the gun)
The Arc voltage
Motor driven generators - Transformer rectifiers - and Inverter designs

23. What is the key advantage of short circuiting transfer?
Minimum distortion due to low heat input
Voltage is the force that overcomes resistance to allow amperage flow
Shielding the molten weld metal from atmospheric contamination
AWS and CSA

24. What term is used to describe when the workpiece is hooked to the negative pole on the power source?
AWS and CSA
Voltage is the force that overcomes resistance to allow amperage flow
The time rate of response for the current rise and fall
(DCEP) Direct Current Electrode Positive or Reverse polarity

25. List the factors that determine the mode of metal transfer
Gas metal arc welding
To prevent leakage - Carbon Dioxide (CO2)
SMAW - GTAW
Welding Current - Filler wire diameter - arc length - type of shielding - position of the weld

26. What happens when the electrode extension is increased?
SMAW - GTAW
To limit the short circuiting current so that spatter is reduced
Shielding the molten weld metal from atmospheric contamination
The resistace to electrical current flow increases with it. Causing the electrode to heat

27. In the GMAW process what does voltage control?
Puddle fluidity
SMAW - GTAW
DCEP (Direct Current Electrode Positive) Reverse Polarity
AWS and CSA

28. Draw a typical volt/amp curve that would be found with a power source designed for SMAW or GTAW
Constant voltage (CV)
5.8 to 12.5 L/min
If you dont know this check your phone
SMAW - GTAW

29. What is an advantage of pulsed arc transfer with GMAW?
...
Reducing the gas source pressure to a constant working pressure
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
Duty cycle

30. What is a solenoid valve and what actuates it?
To limit the short circuiting current so that spatter is reduced
Guns
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

31. What 2 organizations designate specifications for GMAW wires?
By there current carrying capacity
Spatter problems and poor weld appearance
Reducing the gas source pressure to a constant working pressure
AWS and CSA

32. What does a flowmeter do and what does it measure?
Gives arc voltage values to the control system of the feeder
Controls the rate of flow of a shielding gas to the gun nozzle
Welding process that joins metals by heating them with an electric arc
Constant voltage (CV)

33. What is another term for electrode holders for GMAW?
...
Higher 26 to 35 arc volts
Guns
Controls the rate of flow of a shielding gas to the gun nozzle

34. Why is globular transfer generally avoided with GMAW?
Controls the rate of flow of a shielding gas to the gun nozzle
Spatter problems and poor weld appearance
Aluminum wire
Motor driven generators - Transformer rectifiers - and Inverter designs

35. What is the purpose of the pick- up lead on a voltage sensing wire feeder?
Welding Current - Filler wire diameter - arc length - type of shielding - position of the weld
Speed of the feed motor and - starting / stopping electrode feed
...
Gives arc voltage values to the control system of the feeder

36. Why is a line heater required when using GMAW?
Flux cored wires
Controls the rate of flow of a shielding gas to the gun nozzle
Cause flaking - which can clog the liner and contact tube
Dry ice can form within the flow control openings and cause blockage of shielding gas

37. Regulators control_____________ flowmeters SHOW____________.
1/4 inch to 1/2 inch
Pressure - The rate of flow of a shielding gas
Penetration and burn - off rate of the electrode
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground

38. What is the main purpose of 'slope'?
To limit the short circuiting current so that spatter is reduced
...
85%
To prevent drawing of liquid CO2 (Carbon Dioxide)

39. What is the recommended electrode stick- out for .035 solid wire?
1/4 inch to 1/2 inch
Welding Current - Filler wire diameter - arc length - type of shielding - position of the weld
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground
Constant- speed wire feeders and Voltage- sennsing wire feeders

40. What type of power source is commonly used with a voltage sensing wire feeder?
Minimum distortion due to low heat input
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
Aluminum wire
Constant current (CC)

41. What does inductance control?
Wire feed speed - Voltage control
If you dont know this check your phone
Gives arc voltage values to the control system of the feeder
The time rate of response for the current rise and fall

42. What is a typical flow rate of CO2 for short circuit transfer?
Molten metal is separated from the end of the filler wire by a squeezing force created by a magnetic field
5.8 to 12.5 L/min
3
Reducing the gas source pressure to a constant working pressure

43. Draw a typical volt amp curve for a machine that is designed for GMAW
To prevent leakage - Carbon Dioxide (CO2)
3
If you dont know this check your phone
Duty cycle

44. What current and polarity is generally used with GMAW?
Aluminum wire
DCEP (Direct Current Electrode Positive) Reverse Polarity
V groove or U groove
Increasing inductance increases puddle fluidity - improves penatration - makes the bead flatter and smoother - and reduces spatter. To much inductance though will create erratic starts

45. List 3 forms compressed gases may be supplied for welding
Compressed gas cylinder - Liquid filled cylinder - or a Liquid bulk system
SMAW - GTAW
When the filler wire is in direct contract with the base metal
Controls the rate of flow of a shielding gas to the gun nozzle

46. A 10 minute cycle of welding time vs cooling time a given machine can handle.
AWS and CSA
Duty cycle
1/4 inch to 1/2 inch
DCEP (Direct Current Electrode Positive) Reverse Polarity

47. What controls amperage when using GMAW?
Reducing the gas source pressure to a constant working pressure
To prevent leakage - Carbon Dioxide (CO2)
The negative side of a welding unit
Wire feed speed

48. What is the required arc voltage used for short circuit transfer?
12 to 22 arc volts
The time rate of response for the current rise and fall
DCEP (Direct Current Electrode Positive) Reverse Polarity
Minimum distortion due to low heat input

49. What is the purpose of a regulator and what does it indicate on its gauges?
Reducing the gas source pressure to a constant working pressure
Electricaly operated valves that control the flow of shielding gas to the weld zone. The control switch located on the gun
Higher 26 to 35 arc volts
Gas metal arc welding

50. What effect does increasing and decreasing the inductance have on the weld?
Molten metal is separated from the end of the filler wire by a squeezing force created by a magnetic field
Increasing inductance increases puddle fluidity - improves penatration - makes the bead flatter and smoother - and reduces spatter. To much inductance though will create erratic starts
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
Constant voltage (CV)

Test your basic knowledge |

Gas Metal Arc Welding

13 Skills Types | 550 Pages | Only $9.95 | PDF / EPub, Kindle Ready

Top Scores

Link to This Test

Related Subjects