p10-2 task 2

Question 1

the inert gases most commonly used as shielding gases in GTAW are

1. krypton and argon
2. argon and helium
3. neon ans helium
4. hydrogen and argon

Answer 1

b. argon and helium

Question 2

argon is used more extensively than helium because as a shielding gas

1. The arc voltage is higher
2. the penetration achieved as much deeper
3. it produces a smoother, quieter arc
4. the heat input is greater

Answer 2

c. it produces a smoother, quieter arc

Question 3

which shielding gas is most commonly used on light gauge materials

1. hydrogen
2. helium
3. neon
4. argon

Answer 3

d. argon

Question 4

which shielding gas is preferred for thicker, heavier materials?

1. hydrogen
2. argon
3. helium
4. nitrogen

Answer 4

c. helium

Question 5

if gas flow is excessive the result may be

1. trailing shielding gases
2. excessive Arc voltage
3. Arc pre-ignition
4. atmospheric contamination in the world

Answer 5

d. atmospheric contamination in the world

Question 6

why is argon preferred for welding in areas subject to drafts?

1. it is lighter than air
2. it is heavier than air
3. it is less flammable
4. it has a higher ionization potential

Answer 6

b. it is heavier than air

Question 7

the flow metre for shielding gases indicates the

1. pressure in the cylinder
2. volume in the cylinder
3. volume the passes through the torch
4. pressure in the torch

Answer 7

c. volume the passes through the torch

Question 8

most regulators deliver a constant outlet pressure to the flowmeter of approximately

1. 138 kPa (20 psi)
2. 207 kPa (30 psi)
3. 276 kPa (40 psi)
4. 345 kPa (50 psi)

Answer 8

d. 345 kPa (50 psi)

Question 9

the bead configuration produced when argon is used as a shielding gas is

1. wide and shallow
2. deep and narrow

Answer 9

1. wide and shallow

Question 10

which weld bead configuration shown in Figure 1 is produced when helium is used as a shielding gas

Answer 10

a.