Page 178 - CITS - ED - Mechanical

ENGINEERING DRAWING - CITS

Fasteners

Exercise 8.37
Parallel keys
Draw the parallel keys as per IS:2048 to shaft of diameter 180 mm using general formula and as per standard.
(Fig 1A, C, D, F & G)

– Type A - Both ends round R = 22.5 mm.
– Type C - Similar to type A but with counterbore dia 14 mm, counterbore 208.3 deep.
– Type D - Both ends square with counterbore similar to type C.
– Type F- Both ends square with hole for two retaining screws M12.

– Type G - Similar to type D but with a chamfer at 15 .
0
General formula
Diameter of shaft (d) 180 mm.
Width of key 0.25 d + 2 mm
Thickness of key = 0.33 W (1/3W)

Length of key = 2d
Width = 0.25 x 180 + 2 47 mm
Thickness = 1/3 W = 47/3 = 16 mm
Length 2d = 360 mm

Fig 1

Exercise 8.38
Taper keys
Draw the taper keys type A to C as per IS: 2292 to suit the shaft diameter 100 mm. (Fig 2A,B & C)
General formula/sizes

Taper on taper key = 1:100
Length of key approx. 2d
Width (W) = 0.25d + 2 mm

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CITS :Engineering Drawing (Mechanical) - Exercise 8 CITS :Engineering Drawing (Mechanical) - Exercise 8