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41. Estimate the welding speed for Aluminium (Specific energy 2.9 J/mm3) when the

42.

43.

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48.

voltage is 40V and current is 200 A, cross
and welding efficiency is 80%.

A) 67.5 mm/s

C) 75.6 mm/s

sectional area of weld bead is 30 mm?

B) 73.6 mm/s
D) 85 mm/s

Compared with other arc welding processes plasma arc welding has

A) Better arc stability
C) Less thermal distortion

B) Higher energy concentration
D) All the above

SMAW is best suited for workpiece for a whole range of thickness of

A) 1-15mm
७) 3-19mm

8) 7-25mm
0) 15-25 mm

Range of currents employed in SAW process single arc process is

A) 300 - 2000 A
C) 1200 - 5000 A

For electron beam welding, which of the foll
A) Shielded gas
C) Vacuum

8) 700 - 3800 A
D) 600 - 4000 A

lowing are used ?
B) Flux
D) None of the above

Sonotrode in ultrasonic welding does the function of

A) Apply shear stress

B) Coupling between transducer and tip
C) Removing contaminants

D) None of the above

Weld zone size and shape in friction welding is influenced by

A) Amount of heat generated
C) Axial pressure

Findthe heat dissipated by resistance welding

B) Thermal conductivity of material
D) All the above

of a 1mm thick workpiece if heat required

to melt the weld nugget is 380 J for a current of 5000 A and resistance 200 14 and

contact period of 0.1 S.
A) 400 J
©) 198 J

8

8) 1204
ഉ) 5004