A. Thermostat
B. Thermocouple
C. Auto-transformer
D. Heating elements of variable resis-tance material
Related Mcqs:
- The temperature inside a furnace is usually measured by which of the following ?
A. Optical pyrometer
B. Mercury thermometer
C. Alcohol thermometer
D. Any of the above - Which of the following will happen if the thickness of refractory wall of furnace is increased ?
A. Heat loss through furnace wall will increase
B. Temperature inside the furnace will fall
C. Temperature on the outer surface of furnace walls will drop
D. Energy consumption will increase - In direct arc furnace, which of the following has high value ?
A. Current
B. Voltage
C. Power factor
D. All of the above - The material of the heating element for a furnace should have___________?
A. lower melting point
B. higher temperature coefficient
C. high specific resistance
D. all of the above - In a resistance furnace the atmosphere is_____________?
A. oxidizing
B. deoxidising
C. reducing
D. neutral - The electrode of a direct arc furnace is made of____________?
A. tungsten
B. graphite
C. silver
D. copper - In arc furnace the function of choke is______________?
A. to stabilize the arc
B. to imprpve, power factor
C. to reduce severity of the surge
D. none of the above - Ajax Wyatt furnace is started when____________?
A. it is filled below core level
B. it is filled above core level
C. it is fully empty
D. none of the above - By which of the following methods the temperature inside arc nace can be varied ?
A. By disconnecting some of the heating elements
B. By varying the operating voltage
C. By varying the current through heating elements
D. By any of the above method - Properly of low temperature co-eflficient of heating element is desired due to which of the following reasons ?
A. To avoid initial rush of current
B. To avoid change in kW rating with temperature
C. Both (A) and (B)
D. Either (A) or (B)
