MCQ
61. What is the efficiency of an AC welding transformer?
0.6
0.7
0.8
0.9
62. Which of the following characteristic does not define a coated electrode?
Maintenance of arc
Protection frum oxygen
Protection from nitrogen
Preventing other elements into molten metal
63. What is the percentage of carbon present in low alloy steel?
0.15%
0.2%
0.25%
0.3%
64. If the rivets in adjacent rows are staggered and the outermost row has only one rivet, the arrangement of the rivets is called-
chain riveting
zig zag riveting
diamond riveting
criss-cross riveting
65. Oxy-acetylene process is most suited for which of the following process of joining?
Metal wires
Metal sheets
Metal tubes
Metal bars
66. A riveted joint in which the number otrivets decrease from innermost to outer most row is called-
chain riveted joint
diamond rivered joint
criss-cross riveted joint
zig-zag riveted joint
67. What is the amount of electric energy required per kg in de welding operation?
1-4 kWh
3-7 kWh
4-9 kWh
6-10 kWh
68. Diamond riveted joint can be adopted in the case of following type of joint.
butt joit
lap joint
double riveted lap joints
all types of joins
69. For what thickness of a material, in an oxy acetylene is a welding rod used?
10 mm
15 mm
20 mm
25 mm
70. A riveted joint in which every rivet of a row is opposite to other rivet of the outer row, is known as-
chain riveted joint
diamond riveted joint
criss-cross riveted joint
zig-zag riveted joint
71. Which of the following types of fuel gas is commonly used in gas welding?
Biogas
Coal gas
Acetylene
Methane
72. Which of the following could be considered as a related process?
Explosive
Oxy-Hydrogen welding
Oxy-Acetylene cutting
Electron-beam
73. A neutral flame is obtained by supplying-
equal volumes of oxygen and acetylene
more volume of oxygen and less volume of acetylene
more volume of acetylene and less volume of oxygen
none of the above
74. Carburising flame has excess of oxygen supply.
True
False
75. What is the amount of carbon contained by a soft steel wire?
0.1% to 0.18%
0.15% 10.00.22%
0.18% to 0.26%
0.2% to 0.27%
76. In a neutral flame, what is the temperature in the inner core?
3200°C
2100°C
1250°C
2700°C
77. What is the capacity of a light manual welding machine?
100A to 200A
300A to 400A
500A to 700A
800A to 3000A
78. What is the flame temperature of water gas?
2500°C
2800°C
2300°C
3100°C
79. What is the flame temperature of city gas?
1500°C
1600°C
1700°C
1800°C
80. Which material is not used for making non- consumable electrodes?
Carbon
Graphite
Sodium
Tungsten