Electric Welding MCQ PDF

61. In argon arc welding, argon is used as

(a) an agent for heat transfer.
(b) a shield to protect the work from oxidation.
(c) a source of heat.
(d) a flux.

62. In argon arc welding, the argon is used to

(a) prevent oxidation of metal by coming in contact with air.
(b) create inert atmosphere around the work.
(c) obviate the necessity for using flux.
(d) all of the above.

63. Submerged arc process is characterized by

(a) high welding current.
(b) exceptionally smooth beads.
(d) all of the above.
(c) deep penetration.

64. Electrode is not consumed in case of

(a) TIG welding.
(b) atomic hydrogen arc welding.
(c) MIG welding.
(d) all of the above.

65. Unlike TIG welding, MIG welding

(a) needs no post-weld cleansing.
(b) needs no flux.
(c) uses consumable electrodes.
(d) provides complete protection from atmospheric contamination.

66. MIG welding is becoming more and more popular as it

(a) is easy in operation.
(b) has high metal deposit rate.
(c) both (a) and (b).
(d) can be used for both ferrous and nonferrous metals.

67. In MAG (metal active gas) welding the gas used is

(a) argon or helium.
(b) carbon dioxide or its mixture with other gas.
(c) hydrogen.
(d) any of the above.

68. A weld bead of wineglass design is produced in

(a) plasma arc welding.
(b) MAG welding.
(c) electron beam welding.
(d) all of the above.

69. In electro-slag welding, theoretically there is no limit to the

(a) rate of metal deposit.
(b) thickness of weld bead.
(c) temperature of salt bath.
(d) rate of slag consumption.

70. In manual arc welding of mild steel, the metal deposition rate will be about

(a) 10 – 15 kg per hour.
(b) 5 – 10 kg per hour.
(c) 2 – 5 kg per hour.
(d) below 1 kg per hour.

71. In ultrasonic welding, the frequency range is usually

(a) 20 – 60 kHz
(b) 50 – 100 kHz
(c) 100 – 200 kHz
(d) above 250 kHz

72. Welding is not done directly from the supply mains as

(a) its voltage is too high.
(b) it is impracticable to draw heavy currents directly from the supply mains.
(c) its voltage remains fluctuating.
(d) none of the above.

73. AC welding machine cannot be used for

(b) submerged arc welding.
(a) resistance welding.
(c) MIG welding.
(d) atomic hydrogen welding.

74. In electric welding, arc blow can be avoided by

(a) using ac machines.
(b) increasing arc length.
(c) using bare electrodes.
(d) welding away from ground connections.

75. Welding leads have

(a) high current carrying capacity.
(b) high flexibility.
(c) both (a) and (b).
(d) none of the above.

76. The welding load

(a) is always intermittent.
(b) is always continuous and constant.
(c) is always continuous but varying.
(d) may be any one of the above.

77. The load power factor using welding transformer depends on

(a) arc length.
(b) material to be welded.
(c) type of electrode to be used.
(d) all of the above.

78. For power factor correction in a welding circuit, a capacitor is usually connected

(a) across the mains.
(b) across secondary side of welding transformer.
(c) across primary side of welding transformer.
(d) across arcing electrodes.

79. Which of the following is different from the remaining ?

(a) Butt welding.
(b) Electro-slag welding.
(c) TIG welding.
(d) MIG welding.

80. Chipping hammers are used

(a) for slag welding.
(b) for aligning the pieces to be welded.
(c) for removing slag from welding.
(d) for marking spots to be welded.