CWB Welding Inspector Level 3 Exam Prep (Latest 2023/ 2024 Update) Questions and Verified Answers| All Modules Covered| 100% Correct| Grade A

CWB Welding Inspector Level 3 Exam Prep

(Latest 2023/ 2024 Update) Questions and

Verified Answers| All Modules Covered|

100% Correct| Grade A

Q: Fluxes that can dissolve the oxides on Al are ............

Answer:

Halide compounds ( Fluorine, chlorine, Bromine etc.)

Q: Chlorine gas from a Chloride flux in presence of an arc can create poisonous gas called

..........

Answer:

Phosgene (COCL2) or Mustard gas produced by the reaction of chlorine and carbon monoxide in

the presence of intense light

Q: Why are Chlorine fluxes removed completely from the weld region?

Answer:

bcz its hygroscopic. The part will be susceptible for corrosion

Q: What is the drawback of the SMAW welding of Al with Chlorine coated electrodes?

Answer:

1. Cause Lack of Fusion

2. electrodes restricted to Al - Si, Al-Mg-Si and Al- Mg-Si-Cu alloys welding only

3. It cannot be applied to a high magnesium-containing alloy such as AA5083.

Q: At what temp does Al melts?

Answer:

660 C

Q: At what temp does Al oxides melts ?

Answer:

2072 C

Q: True / False?

Fluxes are not a viable route to remove the oxides on the surface during welding

Answer:

True

Q: The thermal conductivity of Al is ......... times that of steel

Answer:

4

Q: True / False?

Among Al alloys ,the thermal conductivity can vary by a factor of two and has a pronounced

effect on the welding parameters.

Answer:

True,

Alloying or impurity elements such as titanium , Lithium , magnanese and magnesium can lower

the thermal conductivity

Q: The melting point of the oxides on the Al surface is ....... times greater than the melting point

of the metal

Answer:

3

Q: True / False?

For Al, for the same welding energy input, weld penetration varies by the ratio of the thermal

conductivity of 6061 T6 (167 W/mK) to that of AA-5083-O (117W/mK), which is 1.43

Answer:

True

Q: For the same heat input, AA-5083 will have a ................. penetration weld than 6061 T6

Answer:

deeper

Q: True / False

3D thermal flow does not extracts more heat necessitating more heat input to get a comparable

weld depth for the two-dimensional heat flow condition

Answer:

False , It does extracts more heat

Q: Which welding processes are not effective on Aluminum ?

Answer:

SMAW, GMAW - Globular or Short circuit... more likely to get inadequate penetration and

excessive weld reinforcement defects

Q: How electrical conductivity varies with Al alloys?

Answer:

by around 50 %

Q: Coefficient of thermal expansion for Al is about _______ that of Steel

Answer:

twice.. means for the same temp rise the dimensional change of the Al will be twice that of steel.

Distortion is higher than steel. Also the bright reflective surface of the bare Al causes distortion

to be more visible than is the case with steel.

Q: Distortion is an issue bcs it can :-

Answer:

1. Have a deterious effect on the subsequent fit-up of the part to the final assembly.

2. Cause the welded component to have an unacceptable appearance

3. Cause an un acceptable cosmetic appearance to the finished part.

4. Cause the joint line to move.

Q: True / False?

The lower modulus of Al wire means that the wire will buckle more readily than a steel wire

when it is contact with the liner and consequently increases the friction drag forces that inhibit

uniform wire feeding

Answer: