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Keyways Index

BS 46 Square Keys and keyway Dimensions

Ref. Standard ..British Standard :BS 46 Part 1 : 1958 Keys and keyways and taper pins. Specification. Keys and keyways



BS 46 Part 1 : 1958 Square Keys and keyway Dimensions

all dimensions in inches


Shaft Diameter Width
Height		   Keyway (Shaft   Keyway (Hub) Radius r
W H   W h
Over To/Inc W & T   Min Max Max Min   Min Max Min Max  
1/4 1/2 1/8   0.124 0.125 0.072 0.078   0.125 0.126 0.060 0.066 0.010
1/2 3/4 3/16   0.187 0.188 0.107 0.113   0.188 0.189 0.088 0.094 0.010
3/4 1 1/4   0.249 0.250 0.142 0.148   0.250 0.251 0.115 0.121 0.010
1 1 1/4 5/16   0.311 0.312 0.177 0.183   0.312 0.313 0.142 0.148 0.010
1 1/4 1 1/2 3/8   0.374 0.375 0.213 0.219   0.375 0.376 0.169 0.175 0.010
1 1/2 1 3/4 7/16   0.437 0.438 0.248 0.254   0.438 0.439 0.197 0.203 0.020
1 3/4 2 1/2   0.499 0.500 0.283 0.289   0.500 0.501 0.224 0.230 0.020
2 2 1/2 5/8   0.624 0.625 0.354 0.36   0.625 0.626 0.278 0.284 0.020
2 1/2 3 3/4   0.749 0.750 0.424 0.43   0.750 0.751 0.333 0.339 0.020
3 3 1/2 7/8   0.874 0.875 0.495 0.501   0.875 0.876 0.387 0.393 0.062
3 1/2 4 1   0.999 1.000 0.566 0.572   1.000 1.001 0.442 0.448 0.062
4 5 1 1/4   1.248 1.250 0.707 0.713   1.250 1.252 0.551 0.557 0.062
5 6 1 1/2   1.498 1.500 0.848 0.854   1.500 1.502 0.661 0.667 0.062


BS 46 Part 1 : 1958 Square Key Dimensions

all dimensions in inches

Width/ Height W & T   Pref. Length
W &T Max Min   From To
1/8 0.127 0.125   3/4 1
3/16 0.190 0.188   3/4 2
1/4 0.252 0.250   3/4 3
5/16 0.314 0.312   3/4 3
3/8 0.377 0.375   1 4
7/16 0.440 0.438   1 1/2 4
1/2 0.502 0.500   2 1/2 5
5/8 0.627 0.625   2 1/2 6
3/4 0.752 0.750   3 1/2 6
7/8 0.877 0.875   3 1/2 6
1 1.003 1.000      
1 1/4 1.253 1.250      
1 1/2 1.504 1.500      


Links Providing information on Keyways
  1. Hercules -Keyways dimensions ...Download of keyway dimensions
  2. Specifying Rectangular Keyways ...MDmetric document - useful check information for my tables
  3. Transeals - Keyways ...Transeals - useful check information for my tables

Keyways Index

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