This set of Welding MCQs focuses on “Resistance Welding Methods”.
1. Which kind of resistance is experienced in upset butt welding?
a) Electric resistance
b) Magnetic resistance
c) Thermal resistance
d) Air resistance
Explanation: In the making of an upset butt welding, there are jaws made of copper, into which the part to be welded is put, and hence a solid contact is made. At this point of contact, while the current flows, it gets transformed into heat because of electric resistance.
2. Which of the following can be easily be welded from flash butt welding process?
c) Cast irons
d) Carbon steel
Explanation: In flash butt welding process, the welding of materials like steels and other iron alloys are easy to weld, except for cast iron. The welding of materials like tin, lead, zinc and antimony cannot be welded using flash butt method.
3. Electrodes used in spot welding are made up of which material?
a) Only Copper
b) Copper and tungsten
c) Copper and chromium
d) Copper and aluminium
Explanation: The electrodes that are employed in the spot welding are required to possess a high amount of electrical and thermal conductivity. Hence, they are primarily made up of copper or copper and tungsten or copper and chromium.
4. How are the metals to be welded connected to each other in spot welding?
a) Electric contact
b) Magnetic field
c) Mechanical pressure
d) Direct contact
Explanation: In spot welding process, the metal or the alloy parts which are to be welded, are heated in their in their zones. To bring these parts in contact with one another, mechanical pressure is applied, causing them to connect.
5. Which of the following method is not used in applying pressure in spot welding process?
a) Hand lever
b) Foot lever
c) Air pressure
d) Hydraulic cylinder
6. Up to what thickness, can steel be welded using spot welding process?
a) 10 mm
b) 11 mm
c) 12 mm
d) 13 mm
Explanation: In spot welding process, to bring the heated parts in contact with one another, mechanical pressure is applied. This pressure can be of three types, by using foot lever, by providing air pressure or by using a hydraulic cylinder. The use of these methods allows steel or other metal parts to be welded up to a thickness of 12 mm.
7. What is the maximum power supply needed for the working of spot welding process?
a) 135 kVA
b) 140 kVA
c) 145 kVA
d) 150 kVA
Explanation: Spot welding can be used for all types of ductile metals. It can also be employed for structures of sheet metals, and can be applied for making of boxes and cans. For its applications, the maximum power that can be needed for this process is 150 kVA.
8. What is the minimum power supply needed for the working of spot welding process?
a) 10 kVA
b) 14 kVA
c) 6 kVA
d) 22 kVA
9. Upset butt welding is majorly used in making of automobile parts.
Explanation: Upset butt welding is mainly used for the manufacture of welding bars, rods, wires or tubing. For the manufacture of automobile parts, such as axles, wheels or frames, flash butt welding is extensively used.
10. In flash butt welding, the forced out metal is called flash.
Explanation: In flash butt welding process, there is a light contact between the edges. A high voltage is supplied when the flashing action takes place. In this process, the metal that is forced out, is called as flash.
Sanfoundry Global Education & Learning Series – Welding.
To practice MCQs on all areas of Welding, here is complete set of 1000+ Multiple Choice Questions and Answers.