Page 74 - CITS - Fitter Trade Practical - Volume -2

FITTER - CITS
Making and replacing damaged keys

Objectives : At the end of this exercise you shall be able to
• assemble using feather key in hub and shaft
• assemble using tapered key in hub and shaft.

Job Sequence

• Assemble hub and shaft with parallel key.
• Assemble hub and shaft with tapered (Gib Head) key.
Parallel key fitting
• Deburr the keyways in the shaft and the Hub, clean the keyways.

• Check the dimensions of shaft and Hub and keyways using precision instruments. (Outside dia of shaft, inside
dia of hub, length, width and depth of keyway) as per the drawing (Fig 1).
• Select a length of key steel (St 60) of suitable cross section depending on the size of the keyway.

• File radius at one end of the key and cut to a length plus 1 mm of the keyway and file other end of the key
(Fig 2).

Fig 1

Fig 2

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CITS : C G & M - Fitter - Exercise 65