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Q 1: A
Keyword “is the most susceptible”.
Weld configuration of U preparation too small angle bevel with another V preparation, see Section 2.4.1 and Figure 2.14.
Q 2: C
See Section 2.6.1 or BS 499-1.
Q 3: B
See Figure 2.28.
Q 4: C
See Figure 2.34.
Q 5: C
Keyword “not, welding inspector”.
See Section 1.1.6.
Q 6: D
See Section 3.3.4.
Q 7: B
Keyword “controlled”, by design throat thickness.
Note: measured by actual leg length.
Q 8: C
Non-planar defects such porosity, slag, …
Planar defects such crack, lamination, lack of fusion, …
Q 9: A
Measurement of arc voltage, voltage as close as the welding arc.
Q 10: C
See Section 1.1.6 – duties of welding inspector.
Q 11: C
See Section 3.6.10.
Q 12: B
Keyword “weld metal deposited per minute”, see BS 499-1.
Q 13: D
See BS 499-1, different between cold lap and overlap.
See Figure 7.1 and Figure 3.22.
Q 14: C
Throat thickness = 19*0.7 = 13.3 mm.
See Section 2.6.2.
Q 15: B
Pre-heat purpose to reduce cooling rate and increase welding speed.
See Section 17.3.3 – Avoid HAZ hydrogen cracking.
Q 16: D
Refer to WPS or see Section 2.4.2 - types of preparation.
Q 17: D
See Section 1.1
Q 18: A
Linear misalignment (1) = (8x10)/100 = 0.8 mm (answer)
Linear misalignment (2) < = 2 mm (max.).
Whichever value is less.
Q 19: B
Keyword “excessive chevron shaped cap ripple”.
Increased travel speed > narrow weld bead > decreased penetration.
See Section 14.3.3 – SAW Process.
Q 20: A
See Section 2.6.2 – concave fillet weld.
See Section 19.1.2 – residual stress.
Refer ISO 5817/6520-1 – code 505.
WIS5-90516b_2a_21-50
Q 21: D
Arc strike > quick cooling > hardening surface, initial point, crack, reduce base metal thickness.
See Section 3.7.1.
Q 22: C
Opening planar defect are more serious than internal defects due to initial point to propagation failure service.
Q 23: A
The minimum light illumination is 350 lux.
The minimum RECOMMENDS light illumination 500 lux.
See Section 1.1.3.
Q 24: D
See Section 13.5.
Function of the filling powder:
· Stabilize the arc.
· Add alloy elements.
· Produce gaseous shield.
· Produce slag.
· Add iron powder.
Q 25: C
Keyword “magnetic forces”.
See Section 11.3.4.
Q 26: B
SAW process high A and V > increase penetration, greater depth to width ratio, susceptible to hot cracking.
See Section 17.4.
Q 27: C
See Section 10.5.1.
Q 28: A
Keyword “nickel and its alloys, TIG, DC-ve”.
See Section 12.2.2.
Q 29: B
Learning from Heat Input formular, see Section 10.3.
Fast travel speed > low heat input > fast cooling rate > high hardness.
See Section 11.3.3.
Q 30: B
DC to AC: reduce arc blow, deflect arc due to the following AC in two directions.
See Section 11.3.4.
Q 31: C
The same answer WIS5-90516b_1a_37.
Q 32: C
See Section 15.1 – disadvantages.
Q 33: C
MMA is manual welding process, constant current power source.
See Figure 11.3.
Q 34: C
Keyword “plate over 25 mm”.
See Figure 13.16.
Q 35: C
Keyword “aluminum”, cleanliness problem with DC polarity.
Q 36: A
Keyword “deepest penetration”, DC+ given deepest penetration compare with AC polarity.
Q 37: C
Bare filler has lowest hydrogen.
Q 38: C
See Section 7.3.
Q 39: C
See Section 10.4.
Q 40: B
See Section 13.1
Travel speed control by welder, wire feed speed and arc length are controlled automatically.
Q 41: C
Keyword “MAG welding plant”, MAG shielding gas should be check “gas flow rate, stick-out length (contact tip to workpiece distance, electrode extension)”.
Note: MAG > constant voltage > arc length constant >
- If increase stick-out length (increase voltage), decreased current, less penetration, or
- If decrease stick-out length > increase current > depth penetration.
Best answer C, see Section 22.5.
Q 42: C
Keyword “T joint, highest resistance”,
See Section 2.6.2 – Concave fillet weld.
Q 43: A
Lear more in the WPS, and heat input calculation, see Section 10.3.
Heat input = 6.5 or 12 kJ/mm > too high.
Heat input = 1.2 Jouls/mm > too low.
Q 44: C
Throat thickness = 15*0.7 = 10.5 mm, actual is 8.5 mm less than design throat thickness > concave fillet weld.
See Section 2.6.2.
Q 45: D
Keyword “MMA, most difficult control”.
MMA is manual welding process, constant current power source, control arc length by welder.
See Figure 10.1.
Q 46: B
Keyword “sub-zero condition or temperature”.
Q 47: C
Preheat temperature and avoid cold cracking see Figure C2 of EN 1011-2.
Q 48: D
Keyword “Charpy V notch test”.
See Section 4.1.3.
Q 49: B
Keyword “high heat input” > decrease travel speed > weave bead > low toughness.
Q 50: D
Keyword “creep strength or creep resistance”. See Section 7.3.