WIS5-90516b Part 2

(Các phần này đã thay đổi trong phần handout)

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.