Shaft Couplings 125
dharm
d:\N-Design\Des7-1.pm5 Seventh Print
7.5.3 Cushion Coupling
One of the most commonly used flexible couplings now-a-days is the cushion coupling. The H.P
rating of these couplings for various speeds, range from 0.2 to 450.
The tyre of the coupling is made of natural and synthetic rubber, impregnated with
canvas or rayon. The hubs are made of C I or steel (Fig. 7.13).
R
2 KEYS,
W×TD 0.2 D
0.2 D0.2 D 0.5 D2D
0.5 D 1.2 D
3 0.2 D 0.2 D 30.5 DD
1.5 D
1.5 D2.75 D
6, 0.25 D SOCKET
HD CAP SCR EQUI-SP
3D
4D
Fig. 7.13 Cushion couplingTHEORY QUESTIONS
7.1 What is a shaft coupling?
7.2 Name different types of shaft couplings. What is the basis, on which shaft couplings are classi-
fied?
7.3 Name three types of rigid shaft couplings. State why they are called rigid.
7.4 State where and why split-muff coupling is used in preference to solid muff coupling.
7.5 What is a flange coupling and why is it so named?
7.6 Why are the annular recesses provided at the side of flanges in a protected flange coupling?
7.7 How flanges are made in a marine coupling?
7.8 What are the uses of a flexible coupling?
7.9 What is a universal coupling? Why it is so named?
7.10 Describe how a compression coupling transmits power from one shaft to another.
7.11 Differentiate between:
(a) Butt-muff coupling and half-lap muff coupling,
(b) Rigid coupling and flexible coupling,
(c) Flange coupling and flexible coupling,
(d) Bushed pin type flange coupling and cushion coupling, and
(e) Cone coupling and claw coupling.