MCQ
81. What is the order of temperature of heat produced in an electric arc furnace?
3000°C-4000°C
4000°C-5000°C
5000°C-6000°C
6000°C-7000°C
82. Why is carbon used in carbon arc welding?
Generation of more heat at electrode tip
Generation of less heat at electrode tip
Provides coating
Fixed polarity is maintained
83. In are welding process, the high quality alternator functions at what frequency?"
250 Hz
300 Hz
350 Hz
400 Hz
84. With an increase in the heat input of are welding method, how does it affect the required current?
Increases
Decreases
Remains sane
No relation
85. What amount of electricity gets converted into heat energy in an arc welding process?
0.25kWh
0.75kWh
1kWh
2kWh
86. Which bead character is seen due to too high welding current?
Pilling of metal
Pilling of weld metal
Excess splatter
Small bead formation
87. What is the temperature of the negative electrode in metal arc welding?
2200°C
2300°C
2400°C
2500°C
88. Which kind of resistance is experienced in upset butt welding?
Electric resistance
Magnetic resistance
Thermal resistance
Air resistance
89. The distance from the center of arc to the tip of electrode is called what?
Arc distance
Arc length
Arc crater
Arc depth
90. What is the capacity of an automatic welding machine?
100A 10 200A
300A to 400A
500A to 700A
800A to 3000A
91. What is the temperature at the positive terminal in carbon arc welding?
3800°C
3900°C
4000°C
4100°C
92. With an increase in the heat input of are welding method, how does it affect the voltage applied?
Increases
Decreases
Remains same
No relation
93. The process of carbon arc welding is not used for which of the following material?
Copper
Bronze
Aluminium
Iron
94. Which of the following is not a metal joining process?
Riveting
Bending
Pressing
Brazing
95. What is the temperature at the negative terminal in carbon arc welding?
3000°C
3100°C
3200°C
3300°C
96. What is the temperature of the positive electrode in metal arc welding?
2300°C
2400°C
2500°C
2600°C
97. What is the length of the arc generally?
1mm-2mm
2mm-3mm
3mm-4mm
4mm-5mm
98. Which gas is used as a protection in carbon arc welding?
Carbon dioxide
Carbon monoxide
Carbon tetrafluoride
Methane
99. In flash butt welding, the forced out metal is called flash.
True
False
100. Which of the following can be easily be welded from flash butt welding process?
Tin
Lead
Cast irons
Carbon steel