1. Cotter joint is used when the members are subjected to which type of stresses?
a) Axial tensile
b) Axial compressive
c) Axial tensile or compressive
d) None of the mentioned
Explanation: Cotter joint is used when axial forces are applied.
2. The principle of wedge action is used in cotter joint.
a) True
b) False
Explanation: Wedge action imparts tightening to the cotter joint.
3. Can the cotter joint be used to connect slide spindle and fork of valve mechanism?
a) True
b) False
Explanation: As long as axial forces act, cotter joint can be employed.
4. Which of the following is not a part of cotter joint?
a) Socket
b) Spigot
c) Cotter
d) Collar
Explanation: There is no point of mentioning collar alone in a cotter joint. It has to be a spigot collar or socket collar.
5. Cold riveting holds the connected parts better than hot riveting.
a) True
b) False
Explanation: The compression of connected parts in hot riveting causes friction, which resist sliding of one part with respect to other. This force is greater in hot riveting.
6. In cold riveting like hot riveting shank is subjected to majorly tensile stress.
a) True
b) false
Explanation: In cold riveting there is no reduction in length and hence no tensile stress. Shear stress dominates.
7. Determine the width of the cotter used in cotter joint connecting two rods subjected to axial load of 50kN and permissible shear stress in cotter is 50N/(mm² ). Given thickness of cotter=10mm
a) 50mm
b) 100mm
c) 150mm
d) 25mm
Explanation: Cotter is subjected to double shear hence width=P/(2*τ*t).
8. If joint is to fail by crushing of socket collar then estimate the diameter of socket collar. Given Permissible compressive stress= 126.67 N/mm².; Spigot dia=65mm; thickness 0f collar=15mm
a) 131mm
b) 139mm
c) 141mm
d) 149mm
Explanation: Compressive stress= P/ [(socket dia-spigot dia)*thickness].
9. Cotter joint can be used to connect two rods for torque transmission purpose.
a) True
b) False
Explanation: Cotter Joint is never used to connect two rods for torque transmission purpose.
10. Thickness of plate is required more in welding than in riveting.
a) True
b) False
Explanation: In riveting, cross section is weakened due to the holes and to compensate this, thicker plates are required in riveting.