Which of the following keys is used for connecting the pulley with shaft?

Question

Question

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ALP CBT 2 Fitter Previous Paper: Held on 23 Jan 2019 Shift 1

Answer 1

Explanation:

Gib head keys are specially manufactured machine keys with a projecting end that resembles the end of a gib and serves as a stop mechanism on a rotating shaft.
These keys are commonly used in engines and motors, gear reducers, transmissions, and motor shafts to hold pulleys and gears tightly to the rotating shaft.
Classification of keys:

Woodruff key	This is a semicircular key and it fits on to the shaft on which matching recesses are cut. The top portion of the key projects out and fits in the keyway cut on the hub. This key is particularly useful in tapered fittings of shafts. It is a semicircular key used for transmitting light torque.
Hollow saddle key	One face of this key has a curvature to match with that of the shaft surface. It has a taper of 1 in 100 and is driven in through the keyway. The hub is held on the shaft due to friction. This key is useful only for light-duty transmission.
Parallel key or feather key	This is the most commonly used key, used for transmitting unidirectional torque.
Taper and jib-headed key	It is used for transmitting more torque. It is not good for high-speed applications.
Flat saddle key	This is considered to be stronger than the hollow saddle key. This is not suitable for heavy-duty transmission.