Machine Design online quiz on “Clamp Coupling & Rigid Flage & Coupling Bushed Pin Flexible Coupling”.
1. Clamp coupling employ bolts.
a) True
b) False
Answer: a
Clarification: The two halves of sleeve are clamped together by bolts.
2. Entire torque is transmitted by friction in the clamp coupling.
a) True
b) False
Answer: b
Clarification: Some torque is transferred by friction and some by key.
3. Does shaft has to be shifted i axial direction to remove clamp coupling.
a) Yes
b) No
Answer: b
Clarification: Clamp coupling unlike muff coupling is easily removed without shifting the shaft in axial direction.
4. If shaft diameter is 40mm, calculate the diameter of sleeves in clamp coupling.
a) 100mm
b) 80mm
c) 60mm
d) 40mm
Answer: a
Clarification: Dia=2.5d.
5. If shaft diameter is 40mm, calculate the length of sleeves in clamp coupling.
a) 80mm
b) 140mm
c) 100mm
d) 120mm
Answer: b
Clarification: L=3.5d.
6. If 8 bolts are emplaced in a clamp coupling with shaft diameter 80mm d, calculate the tensile force on each bolt if coefficient of friction is 0.3 and torque transmitted is 4000N-m.
a) 51234.4N
b) 45968.3N
c) 41666.7N
d) None of the listed
Answer: c
Clarification: P=2M/fdn.
7. If 8 bolts are emplaced in a clamp coupling with shaft diameter 80mm d, calculate the diameter of each bolt if coefficient of friction is 0.3 and torque transmitted is 4000N-m. Permissible tensile stress is 80N/mm².
a) 27mm
b) 25mm
c) 23mm
d) 21mm
Answer: a
Clarification: Ax80=2M/fdn.
8. Power is transmitted by only in rigid flange coupling.
a) True
b) False
Answer: b
Clarification: Power is transmitted by key as well as bolts.
9. If shaft diameter is 60mm, how many bolts are recommended for rigid flange coupling?
a) 2
b) 3
c) 4
d) 5
Answer: c
Clarification: If shaft diameter is between 40mm and 100mm, 4 bolts are used.
10. Determine the diameter of the bolts used in rigid flange coupling if transmitted torque is 270N-m, pitch circle diameter=125mm and four bolts are emplace in the coupling. Permissible shear stress in the bolts is 70N/mm².
a) 3.8mm
b) 3.6mm
c) 4.4mm
d) 4mm
Answer: c
Clarification: d²=8M/πDNτ.
11. The hub is treated as a solid shaft while calculating torsional shear stress in the hub.
a) True
b) False
Answer: b
Clarification: Hub is treated as a hollow shaft.
12. Find the shear stress in a flange at the junction of hub in rigid flanged coupling if torsional moment is 2980N-m and diameter of hub being 125mm. Also the thickness of flange is 25mm.
a) 6.77N/mm²
b) 10.24N/mm²
c) 4.84N/mm²
d) 4.22N/mm²
Answer: c
Clarification: τ=2M/πd²t.
13. If shaft diameter is 30mm and number of pins emplaced are 6, then the diameter of the pin will be?
a) 6.4mm
b) 5.6mm
c) 6.1mm
d) 5.9mm
Answer: c
Clarification: d₁=.5d/√N.
14. Calculate the force acting on the each pin in flexible coupling if torque transmitted is 397N-m and PCD=120mm with number of pins 6.
a) 1400.3N
b) 1102.8N
c) 1320.3N
d) None of the listed