Manufacturing Processes Questions and Answers for Aptitude test on “Friction Welding – 4”.
1. In Direct Drive Friction Welding, energy is supplied by _____
a) an electromagnet
b) a capacitor
c) an electric motor
d) a heating unit called heater
Answer: c
Clarification: Direct Drive Friction Welding is a variation of friction welding in which the energy required to make the weld is supplied by the welding machine through a direct motor connection for a preset period of the welding cycle.
2. Which of the following holds true about direct drive friction welding?
a) Both the workpieces are restrained from motion
b) Among two workpieces, the one attached to motor-driven unit is restrained from motion
c) Among two workpieces, the one which is not attached to motor-driven unit is restrained from motion
d) Both the workpieces are moving relative to each other
Answer: c
Clarification: In Direct Drive Friction Welding, one of the workpieces is attached to a motor-driven unit while the other is restrained from rotation. The motor-driven workpiece is rotated at a predetermined constant speed.
3. _____ generated during friction welding is coherent.
a) Burr
b) Molten metal
c) Flash curl
d) Fly ash
Answer: c
Clarification: The flash curl generated during welding is coherent, will not flake off, and can often be left intact if design and engineering considerations allow. Alternately, parts can frequently be designed to accommodate the flash curl in a recess (flash trap).
4. Part geometry and accessibility of the flash are the factors which decide flash removal process.
a) True
b) False
Answer: a
Clarification: In many cases, if the weld flash must be removed, this can be accomplished on the welder as an integrated part of the machine cycle. Part geometry and accessibility of the flash are the two major factors which determine whether on-machine flash removal can be incorporated, and which system can be employed.
5. How many flash removal systems are there?
a) 2
b) 3
c) 4
d) 5
Answer: c
Clarification: Available systems are:
• Shearing–outside
• Shearing–inside
• Plunge Cut–one axis
• Plunge Cut–two axis.
6. Which of the following components of an aircraft is/are not friction welded?
a) Gears
b) Hooks bolt
c) Shafts
d) Hydraulic cylinders
Answer: d
Clarification: Aircraft/ aerospace components which are friction welded include compressor rotors, fan shafts, cluster gears, landing gear components, bi-metallic rivets and hook bolts, aluminium heat pipes, and cryogenic rocket components.
7. Friction welding one of the leading methods of joining different metals.
a) True
b) False
Answer: a
Clarification: Proven reliability of friction welded connections, coupled with the process advantages such as being clean, fast, consistent, and free of operator-induced error, makes friction welding one of the leading methods of joining flanges to valve bodies, drill pipe, high-pressure hose couplings, and manifold tubes.
8. Friction welding produces a _____ bond.
a) metallic
b) metallurgical
c) ionic
d) co-ordinate
Answer: b
Clarification: Friction welding produces a metallurgical bond strong enough to take the high torque and highly loaded rotary tension due to directional drilling.
9. Which of the following is not the advantage of friction welding?
a) No smoke generation during the process
b) Less sparks are produced during the process
c) Applicable for all metals
d) Time saving process
Answer: c
Clarification: The advantages of this process such as no smoke, fumes or gases, or few sparks produced, and the fact that the process is machine-controlled, make it suitable for use in potentially explosive or hazardous environments. The machine can be fully automated so the operator can be safely located out of harm’s way. This process is not applicable to non-forgeable metals.
10. Which of the following set is not joined by friction welding process?
a) Aluminium to Steel
b) Copper to Aluminium
c) Copper to Titanium
d) Rubidium to Caesium
Answer: d
Clarification: Metal combinations not normally considered compatible are joined by friction welding, such as aluminium to steel, copper to aluminium, titanium to copper, and nickel alloys to steel.
Processes for Aptitude test,