1. Which of the following NDT methods can only detect surface breaking defects?
MPI
DPI
UT
RT
2. Which of the following is applicable to electrode efficiency?
The mass of metal deposited as a percentage of the mass core wire melted
Iron powder electrodes have efficiencies above 100%
Electrodes of high efficiencies tend to procedure welds of a smooth flat profile
Both a and b
3. Cellulose electrodes have which of the following properties?
Viscous slag, large volumes of shielding gas and UTS values above 90,000 PSI
Large volumes of shielding gas, hydrogen contents>15 ml per 100g of weld metal deposited and should be never baked
Large volumes of shielding gas, high spatter contents and hydrogen levels < 15 ml per 100g of weld metal deposited
None of the above
4. Drooping characteristic power source is suitable for
TIG and MMA
MIG and TIG
TIG and PAW
All of the above
5. What is a weld junction?
The area containing the HAZ and the weld metal
The boundary between the fusion zone and the HAZ
Both 1 and 2
None of the above
6. The likelihood of a brittle fracture in steels will increase with
A slow cooling rate
A reduction in-service tem to sub-zero conditions
Both 1 and 2
All of the above
7. A common gas/mixture used in MIG welding of nickel alloys to combine good levels of penetration with good arc stability would be :
100% CO2
100% argon
80% argon 20%CO2
98% argon 2% oxygen
8. When visually inspecting a completed single V-butt weld cap you would certainly assess
cap height
toe blend
weld width
All of the above
9. What two functions in arc welding must be in equilibrium to enable a stable arc to be established?
Arc voltage
Current
Wire-electrode feed rate
Metal burn- off rate
10. Which of the following destructive tests is not normally required for welder performance test?
Bend tests
Macro examination
Impact tests
Fracture tests
11. In the welding of austenitic pipe work, the bore is usually purged with argon to
Prevent formation of porosity in the weld
Prevent burn-through in the root run
Prevent oxidation of the root bead
None of the above
12. MIG welded joints are susceptible to lack of fusion problems. Due to
Poor maintenance of equipment
Incorrect settings
Poor inter-run cleaning
All the above
13. Reason for Incomplete penetration in a single ‘V’ butt joint could be
Root gap too large
Root gap too small
Step up rectifier
High heat input
14. During examination of a aluminium weld joint, macro etching may reveal:
Weld defect
Weld decay
Linear indications
Lack of inter-run penetration
15. What type of power characteristic is required for manual welding?
Constant voltage
DC generator
Drooping characteristic
None of the above
16. Excessively high voltage in submerged arc welding would result in:
Lack of fusion and spatters
Excessive flux melting
Slag removal difficulties
None of the above
17. Undercut is principally caused by:
Excessive amps
Excessive volts
Excessive travel speed
All the above
18. Which electrode classification would be relevant to AWS A5.1-81?
E 6013
E 5133
E 7018 – G
None of the above
19. Hydrogen controlled electrodes were developed principally for
The prevention of porosity
The prevention of cracking
Replacing the costly electrodes
None of the above
20. E6014 electrode would most probably used for welding
Low pressure pipework
High- pressure pipework
Vertical down welding in heat exchange
When low hydrogen welds are required
21. For welding of carbon steel with thickness more than 100 mm, which of the following welding processes would be the most suited?
TIG
Electro-slag
Manual metal arc
Plasma arc
22. Lap joints would have a
fillet weld
corner joint
butt-weld with single V
single-bevel butts with long edges
23. Cold lapping is used for
Lack of fusion at the toe of a weld
Overlap
Cold cracking
Both a and b
24. ‘Toe blending’ is important as it may affect
Corrosion
Fatigue life
Both a and b
All of the above
25. A welding procedure is useful to :
Give information to the welder
Give information to the inspector
Give ‘confidence’ to a product
All of the above
26. The inclusion of an inductance in the welding circuit when using MIG/MAG welding process is to ;
Control the rate of patter in the dip transfer mode
Enable the welder to weld in position with the spray transfer mode
Both a and b
None of the above
27. Welding flux
Melts the base metal
Protects the weld pool from atmospheric contamination
Both a and b
None of the above
28. In a bend test the face of the specimen is in tension and the root is in compression. What type of test is being carried out?
Root bend test
Side bend test
Face bend test
None of the above
29.The British code for visual inspection requirements is:
BS 4872
BS 499
BS 4870
None of the above
30. With respect to welding procedure specification (WPS), a change in essential variable will lead to
Re-qualification of the weld procedure.
Possible changes in the weld’s microstructure.
Possible changes in the mechanical properties.
All the above
31. The steel composition in a structural contract is changed from 0.15% carbon 0.6% manganese, to 0.2% carbon 1.2% manganese. This might influence the incidence of:
Heavy porosity with blow holes
Cracking in the weld area
Underfill in filler pass
Lack of fusion
32. The predominant structure of an hyper-eutectoid steel that has been quenched at above its upper critical point will be:
Austenite
Martensite
Ferrite
Sorbite
33. Which of the following steels is likely to be more susceptible to hydrogen cracking?
Carbon equivalent of less than 0.15 %
Carbon equivalent of 0.25%
Carbon equivalent of 0.18%
Carbon equivalent of 0.43%
34. A correctly made tack weld should slope from the middle to the ends in order to:
Aid better penetration at the join-up
Prevent porosity
Both a and b
None of the above
35. The use of flux with gas shielded metal arc welding allows:
Sheet metal to be welded
A stable arc when using high current densities
Aluminium to be welded
Less dilution of the weld by the parent metal
36. A steel described as QT will have improved tensile properties because it has been
Been heat-treated
Been quality tested
Both a and b
None of the above
37. In the submerged arc welding process, the use of excessive high voltages would result in?
Insufficient flux melting
Excessive flux melting
Slag removal difficulties
Excessive spatter
38. What does the 70 represent on an E70 10 AWS A5.1 classified electrode?
70 n//mm2 min UTS
70 grade steel
70,000 P.S.I min yield strength
70,000 PSI min UTS
39. Which element in steel if present in significant amounts may lead to hot shortness
Phosphorus
Manganese
Sulphur
None of the above
40. Which of the following elements if present in significant quantities in steel may lead to cold shortness
Calcium
Phosphorus
Hydrogen
Copper
1 thought on “Preparatory Questions (Set – 5)”
Nambete Luyadisa
I have a little doubt for the response to the question 24. ‘Toe blending’ is important as it may affect.
I think toe blending may affect Fatigue life:
Toe
Boundary between a weld face and the parent metal or between runs. This
is a very important feature of a weld since toes are points of high stress
concentration and often are initiation points for different types of cracks (eg
fatigue and cold cracks).
And
Due to the smooth blending between the weld face and the surrounding parent
material, the stress concentration effect at the toes of the weld is reduced
compared with the previous type. This is why this type of weld is highly desired
in applications subjected to cyclic loads where fatigue phenomena might be a
major cause for failure.
Figure 2.31
I have a little doubt for the response to the question 24. ‘Toe blending’ is important as it may affect.
I think toe blending may affect Fatigue life:
Toe
Boundary between a weld face and the parent metal or between runs. This
is a very important feature of a weld since toes are points of high stress
concentration and often are initiation points for different types of cracks (eg
fatigue and cold cracks).
And
Due to the smooth blending between the weld face and the surrounding parent
material, the stress concentration effect at the toes of the weld is reduced
compared with the previous type. This is why this type of weld is highly desired
in applications subjected to cyclic loads where fatigue phenomena might be a
major cause for failure.
Figure 2.31