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Test your basic knowledge |
Gas Metal Arc Welding
Start Test
Study First
Subject
:
engineering
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 is another term for electrode holders for GMAW?
12 to 22 arc volts
Guns
Speed of the feed motor and - starting / stopping electrode feed
Puddle fluidity
2. List 3 forms compressed gases may be supplied for welding
The time rate of response for the current rise and fall
To prevent leakage - Carbon Dioxide (CO2)
Compressed gas cylinder - Liquid filled cylinder - or a Liquid bulk system
If you dont know this check your phone
3. What is the recommended electrode stick- out for .035 solid wire?
1/4 inch to 1/2 inch
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
When the filler wire is in direct contract with the base metal
15 feet (4.5 meters)
4. Give a description of 'pinch effect'
Penetration and burn - off rate of the electrode
SMAW - GTAW
Constant current (CC)
Molten metal is separated from the end of the filler wire by a squeezing force created by a magnetic field
5. What are the 2 types of wire feeders available?
Molten metal is separated from the end of the filler wire by a squeezing force created by a magnetic field
Welding process that joins metals by heating them with an electric arc
Constant- speed wire feeders and Voltage- sennsing wire feeders
Pressure vessels and the piping industry
6. Why is the term GMAW preferred over MIG or MAG?
Flux cored wires
Penetration and burn - off rate of the electrode
Constant current (CC)
These terms are quite restrictive and often technically incorrect
7. What is the preferred drive roll design for solid wires?
V groove or U groove
To prevent leakage - Carbon Dioxide (CO2)
Wire feeds smoothly (yet will slip should a problem occur in the gun)
If you dont know this check your phone
8. What does voltage do in an electrical circuit?
The time rate of response for the current rise and fall
Increasing inductance increases puddle fluidity - improves penatration - makes the bead flatter and smoother - and reduces spatter. To much inductance though will create erratic starts
3
Voltage is the force that overcomes resistance to allow amperage flow
9. 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
(DCEP) Direct Current Electrode Positive or Reverse polarity
If you dont know this check your phone
1/4 inch to 1/2 inch
10. What effect does increasing and decreasing the inductance have on the weld?
These terms are quite restrictive and often technically incorrect
20 to 200 times per second
Constant current (CC)
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. A pull type drive system is usually used on what type of material?
Gas metal arc welding
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground
Aluminum wire
Reducing the gas source pressure to a constant working pressure
12. What is the effect of too much slope?
Controls the rate of flow of a shielding gas to the gun nozzle
Insufficient current to melt the wire off cleanly
Constant- speed wire feeders and Voltage- sennsing wire feeders
5.8 to 12.5 L/min
13. What is the reason glass 'tube' type flowmeters must have the tube mounted truly vertical?
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)
To prevent drawing of liquid CO2 (Carbon Dioxide)
14. What type of power source is used with a constant speed wire feeder?
Puddle fluidity
15 feet (4.5 meters)
12 to 22 arc volts
Constant voltage (CV)
15. Why must CO2 cylinders be used in the vertical position?
To prevent drawing of liquid CO2 (Carbon Dioxide)
1/4 inch to 1/2 inch
Constant- speed wire feeders and Voltage- sennsing wire feeders
Aluminum wire
16. What controls the wire speed on a voltage sensing wire feeder?
Generally not as accurate
Short- circuiting transfer - Globular transfer - Spray transfer
The Arc voltage
Aluminum wire
17. What is the maximum distance that hard wire can be successfully pushed?
Spatter problems and poor weld appearance
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
To prevent leakage - Carbon Dioxide (CO2)
15 feet (4.5 meters)
18. Is the arc voltage for spray transfer higher or lower than that used for short circuit transfer?
85%
Higher 26 to 35 arc volts
Minimum distortion due to low heat input
12 to 22 arc volts
19. Draw a typical volt/amp curve that would be found with a power source designed for SMAW or GTAW
SMAW - GTAW
If you dont know this check your phone
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 feeds smoothly (yet will slip should a problem occur in the gun)
20. 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)
Gas metal arc welding
1/4 inch to 1/2 inch
Duty cycle
21. What power sources are used with the GMAW Process?
If you dont know this check your phone
Motor driven generators - Transformer rectifiers - and Inverter designs
...
The Arc voltage
22. A machine with a 70% duty cycle can run at its max for 7 minutes with a cooling cycle of only _ minutes.
By there current carrying capacity
Pressure - The rate of flow of a shielding gas
3
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
23. What processes are constant current (CC) power sources designed to be used with?
If you dont know this check your phone
5.8 to 12.5 L/min
Pressure vessels and the piping industry
SMAW - GTAW
24. What controls amperage when using GMAW?
12 to 22 arc volts
Constant- speed wire feeders and Voltage- sennsing wire feeders
Gas metal arc welding
Wire feed speed
25. Draw a typical volt amp curve for a machine that is designed for GMAW
The Arc voltage
The negative side of a welding unit
If you dont know this check your phone
To prevent leakage - Carbon Dioxide (CO2)
26. In the GMAW process what does voltage control?
Puddle fluidity
Pressure - The rate of flow of a shielding gas
Motor driven generators - Transformer rectifiers - and Inverter designs
Shielding the molten weld metal from atmospheric contamination
27. When using flat drive rolls with too much pressure on copper coated solid wires what problem could take place?
5.8 to 12.5 L/min
Increasing inductance increases puddle fluidity - improves penatration - makes the bead flatter and smoother - and reduces spatter. To much inductance though will create erratic starts
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
28. What is the purpose of a regulator and what does it indicate on its gauges?
15 feet (4.5 meters)
The negative side of a welding unit
Puddle fluidity
Reducing the gas source pressure to a constant working pressure
29. What current and polarity is generally used with GMAW?
Pressure - The rate of flow of a shielding gas
Pressure vessels and the piping industry
These terms are quite restrictive and often technically incorrect
DCEP (Direct Current Electrode Positive) Reverse Polarity
30. A 10 minute cycle of welding time vs cooling time a given machine can handle.
Motor driven generators - Transformer rectifiers - and Inverter designs
Duty cycle
To limit the short circuiting current so that spatter is reduced
12 to 22 arc volts
31. What is the disadvantage of the gauge preset type of regulator/flowmeter?
Minutes of elapsed time continually run (out of 10 minutes)
Pressure vessels and the piping industry
Guns
Generally not as accurate
32. What is the purpose of the shielding gas used in GMAW?
AWS and CSA
Shielding the molten weld metal from atmospheric contamination
The Arc voltage
Minimum distortion due to low heat input
33. Why is globular transfer generally avoided with GMAW?
Short- circuiting transfer - Globular transfer - Spray transfer
Spatter problems and poor weld appearance
AWS and CSA
15 feet (4.5 meters)
34. Why is a line heater required when using GMAW?
Dry ice can form within the flow control openings and cause blockage of shielding gas
Minutes of elapsed time continually run (out of 10 minutes)
National Electrical Manufactures Association
SMAW - GTAW
35. What output on the welding machine is used to rate the duty cycle?
Minutes of elapsed time continually run (out of 10 minutes)
Duty cycle
Motor driven generators - Transformer rectifiers - and Inverter designs
Short- circuiting transfer - Globular transfer - Spray transfer
36. What does the abbreviation NEMA stand for?
To prevent leakage - Carbon Dioxide (CO2)
85%
National Electrical Manufactures Association
These terms are quite restrictive and often technically incorrect
37. List the factors that determine the mode of metal transfer
To prevent drawing of liquid CO2 (Carbon Dioxide)
Guns
Welding Current - Filler wire diameter - arc length - type of shielding - position of the weld
Insufficient current to melt the wire off cleanly
38. List several industries that would use GMAW
The negative side of a welding unit
These terms are quite restrictive and often technically incorrect
Constant current (CC)
Pressure vessels and the piping industry
39. List the three methods of metal transfer with GMAW
Insufficient current to melt the wire off cleanly
Short- circuiting transfer - Globular transfer - Spray transfer
These terms are quite restrictive and often technically incorrect
To limit the short circuiting current so that spatter is reduced
40. What is the required arc voltage used for short circuit transfer?
The time rate of response for the current rise and fall
15 feet (4.5 meters)
12 to 22 arc volts
Heat input is less than spray transfer - resulting in less distortion - Used in all positions due to controlling the weld metal freeze
41. How many times per second does short circuiting take place?
20 to 200 times per second
Flux cored wires
Molten metal is separated from the end of the filler wire by a squeezing force created by a magnetic field
3
42. List the basic equipment requirements for the GMAW process
Constant current (CC)
If you dont know this check your phone
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground
20 to 200 times per second
43. In the GMAW process what does amperage control?
The Arc voltage
The negative side of a welding unit
Penetration and burn - off rate of the electrode
Gas metal arc welding
44. What wire are knurled drive rolls most commonly used on?
12 to 22 arc volts
Pressure vessels and the piping industry
To prevent drawing of liquid CO2 (Carbon Dioxide)
Flux cored wires
45. When is the metal transferred with short circuit transfer?
V groove or U groove
5.8 to 12.5 L/min
Welding process that joins metals by heating them with an electric arc
When the filler wire is in direct contract with the base metal
46. How are GMAW guns rated?
By there current carrying capacity
If you dont know this check your phone
Cause flaking - which can clog the liner and contact tube
If you dont know this check your phone
47. List 3 wire drive systems and give a short description of each
By there current carrying capacity
The negative side of a welding unit
(DCEP) Direct Current Electrode Positive or Reverse polarity
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
48. What 2 organizations designate specifications for GMAW wires?
Aluminum wire
Higher 26 to 35 arc volts
Pressure vessels and the piping industry
AWS and CSA
49. Regulators control_____________ flowmeters SHOW____________.
Power source - wire feeder - welding gun - Spooled filler wire - Shielding gas - and a ground
Pressure - The rate of flow of a shielding gas
5.8 to 12.5 L/min
To prevent leakage - Carbon Dioxide (CO2)
50. What is the minimum % value of argon that must be present to use the spray transfer method of GMAW?
85%
Electricaly operated valves that control the flow of shielding gas to the weld zone. The control switch located on the gun
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