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Keyways Index
BS 46 Keys and keyway Dimensions-Parallel Rectangular
Ref Standard ..British Standard :BS 46 Part 1 : 1958 Keys and keyways and taper pins. Specification. Keys and keyways
BS 46 Part 1 : 1958 Keys and keyway Dimensions-Parallel Rectangular
Shaft Diameter
Keyway (Shaft
Keyway (Hub)
Radius r
D
Width
Height
W
H
W
h
Over
To/Inc
W
T
Min
Max
Max
Min
Min
Max
Min
Max
1
1 1/4
5/16
1/4
0.311
0.312
0.146
0.152
0.312
0.313
0.112
0.118
0.010
1 1/4
1 1/2
3/8
1/4
0.374
0.375
0.150
0.156
0.375
0.376
0.108
0.114
0.010
1 1/2
1 3/4
7/16
5/16
0.437
0.438
0.186
0.192
0.438
0.439
0.135
0.141
0.020
1 3/4
2
1/2
5/16
0.499
0.500
0.190
0.196
0.500
0.501
0.131
0.137
0.020
2
2 1/2
5/8
7/16
0.624
0.625
0.260
0.266
0.625
0.626
0.185
0.191
0.020
2 1/2
3
3/4
1/2
0.749
0.750
0.299
0.305
0.750
0.751
0.209
0.215
0.020
3
3 1/2
7/8
5/8
0.874
0.875
0.370
0.376
0.875
0.876
0.264
0.270
0.062
3 1/2
4
1
3/4
0.999
1.000
0.441
0.447
1.000
1.001
0.318
0.324
0.062
4
5
1 1/4
7/8
1.248
1.250
0.518
0.524
1.250
1.252
0.366
0.372
0.062
5
6
1 1/2
1
1.498
1.500
0.599
0.605
1.500
1.502
0.412
0.418
0.062
6
7
1 3/4
1 1/4
1.748
1.750
0.740
0.746
1.750
1.752
0.526
0.532
0.125
7
8
2
1 3/8
1.998
2.000
0.818
0.824
2.000
2.002
0.573
0.579
0.125
8
9
2 1/4
1 1/2
2.248
2.250
0.897
0.905
2.250
2.252
0.619
0.627
0.125
9
10
2 1/2
1 5/8
2.498
2.500
0.975
0.983
2.500
2.502
0.666
0.674
0.187
10
11
2 3/4
1 7/8
2.748
2.750
1.114
1.122
2.750
2.752
0.777
0.785
0.187
11
12
3
2
2.998
3.000
1.195
1.203
3.000
3.002
0.823
0.831
0.187
12
13
3 1/4
2 1/8
3.248
3.250
1.273
1.281
3.250
3.252
0.870
0.878
0.187
13
14
3 1/2
2 3/8
3.498
3.500
1.413
1.421
3.500
3.502
0.980
0.988
0.250
14
15
3 3/4
2 1/2
3.748
3.750
1.492
1.502
3.750
3.752
1.026
1.036
0.250
15
16
4
2 5/8
3.998
4.000
1.571
1.581
4.000
4.002
1.072
1.082
0.250
16
17
4 1/4
2 7/8
4.248
4.250
1.711
1.721
4.250
4.252
1.182
1.192
0.312
17
18
4 1/2
3
4.498
4.500
1.791
1.801
4.500
4.502
1.229
1.239
0.312
18
19
4 3/4
3 1/8
4.748
4.750
1.868
1.878
4.750
4.752
1.277
1.287
0.312
19
20
5
3 3/8
4.998
5.000
2.010
2.020
5.000
5.002
1.385
1.395
0.312
BS 46 Part 1 : 1958 Key Dimensions
Width
Height
W
T
Pref. Length
W
T
Max
Min
Max
Min
From
To
5/16
1/4
0.314
0.312
0.253
0.250
3/4
3
3/8
1/4
0.377
0.375
0.253
0.250
1
4
7/16
5/16
0.440
0.438
0.315
0.312
1 1/2
4
1/2
5/16
0.502
0.500
0.315
0.312
1 3/4
5
5/8
7/16
0.627
0.625
0.441
0.438
2 1/2
5
3/4
1/2
0.752
0.750
0.503
0.500
3
6
7/8
5/8
0.877
0.875
0.629
0.625
3 1/2
6
1
3/4
1.003
1.000
0.754
0.750
1 1/4
7/8
1.253
1.250
0.879
0.875
1 1/2
1
1.504
1.500
1.006
1.000
1 3/4
1 1/4
1.754
1.750
1.256
1.250
2
1 3/8
2.005
2.000
1.381
1.375
2 1/4
1 1/2
2.255
2.250
1.506
1.500
2 1/2
1 5/8
2.505
2.500
1.631
1.625
2 3/4
1 7/8
2.755
2.750
1.881
1.875
3
2
3.006
3.000
2.008
2.000
3 1/4
2 1/8
3.256
3.250
2.133
2.125
3 1/2
2 3/8
3.506
3.500
2.383
2.375
3 3/4
2 1/2
3.756
3.750
2.508
2.500
4
2 5/8
4.008
4.000
2.633
2.625
4 1/4
2 7/8
4.258
4.250
2.883
2.875
4 1/2
3
4.508
4.500
3.010
3.000
4 3/4
3 1/8
4.758
4.750
3.135
3.125
5
3 3/8
5.008
5.000
3.385
3.375
Links Providing information on Keyways
Mitcalc.com ...Excel based programme
allowing detailed design of shaft connection (19 Eur)Hercules -Keyways dimensions
...Download of keyway dimensionsSpecifying Rectangular Keyways
...MDmetric document - useful check information for my tablesTranseals - Keyways
...Transeals - useful check information for my tables
Keyways Index
