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Shaft Key Seat Depth Control Values S and T for Shaft and Hub ANSI B17.1
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Shaft Key Seat Depth Control Values S and T for Shaft and Hub ANSI B17.1
Keyseat Alignment Tolerances: A tolerance of 0.010 inch, max is provided for offset (due to parallel displacement of keyseat centerline from centerline of shaft or bore) of keyseats in shaft and bore. The following tolerances for maximum lead (due to angular displacement of keyseat centerline from centerline of shaft or bore and measured at right angles to the shaft or bore centerline) of keyseats in shaft and bore are specified: 0.002 inch for keyseat length up to and including 4 inches; 0.0005 inch per inch of length for keyseat lengths above 4 inches to and including 10 inches; and 0.005 inch for keyseat lengths above 10 inches.
All Dimensions are given in inches
Shafts, Parallel
and Taper |
Hubs, Parallel
|
Hubs, Taper
|
||||
Nominal Shaft
|
Square
|
Rectangular
|
Square
|
Rectangular
|
Square
|
Rectangular
|
Diameter
|
S
|
S
|
T
|
T
|
T
|
T
|
1/2
|
0.430
|
0.445
|
0.560
|
0.544
|
0.535
|
0.519
|
9/16
|
0.493
|
0.509
|
0.623
|
0.607
|
0.598
|
0.582
|
5/8
|
0.517
|
0.548
|
0.709
|
0.678
|
0.684
|
0.653
|
11/16
|
0.581
|
0.612
|
0.773
|
0.742
|
0.748
|
0.717
|
3/4
|
0.644
|
0.676
|
0.837
|
0.806
|
0.812
|
0.781
|
13/16
|
0.708
|
0.739
|
0.900
|
0.869
|
0.875
|
0.844
|
7/8
|
0.771
|
0.802
|
0.964
|
0.932
|
0.939
|
0.907
|
15/16
|
0.796
|
0.827
|
1.051
|
1.019
|
1.026
|
0.994
|
1
|
0.859
|
0.890
|
1.114
|
1.083
|
1.089
|
1.058
|
1-1/16
|
0.923
|
0.954
|
1.178
|
1.146
|
1.153
|
1.121
|
1-1/8
|
0.986
|
1.017
|
1.241
|
1.210
|
1.216
|
1.185
|
1-3/16
|
1.049
|
1.080
|
1.304
|
1.273
|
1.279
|
1.248
|
1-1/4
|
1.112
|
1.144
|
1.367
|
1.336
|
1.342
|
1.311
|
1-5/16
|
1.137
|
1.169
|
1.455
|
1.424
|
1.430
|
1.399
|
1-3/8
|
1.201
|
1.232
|
1.518
|
1.487
|
1.493
|
1.462
|
1-7/16
|
1.225
|
1.288
|
1.605
|
1.543
|
1.580
|
1.518
|
1-1/2
|
1.289
|
1.351
|
1.669
|
1.606
|
1.644
|
1.581
|
1-9/16
|
1.352
|
1.415
|
1.732
|
1.670
|
1.707
|
1.645
|
1-5/8
|
1.416
|
1.478
|
1.796
|
1.733
|
1.771
|
1.708
|
11-1/16
|
1.479
|
1.541
|
1.859
|
1.796
|
1.834
|
1.771
|
1-3/4
|
1.542
|
1.605
|
1.922
|
1.860
|
1.897
|
1.835
|
11-3/16
|
1.527
|
1.590
|
2.032
|
1.970
|
2.007
|
1.945
|
1-7/8
|
1.591
|
1.654
|
2.096
|
2.034
|
2.071
|
2.009
|
11-5/16
|
1.655
|
1.717
|
2.160
|
2.097
|
2.135
|
2.072
|
2
|
1.718
|
1.781
|
2.223
|
2.161
|
2.198
|
2.136
|
2-1/16
|
1.782
|
1.844
|
2.287
|
2.224
|
2.262
|
2.199
|
2-1/8
|
1.845
|
1.908
|
2.350
|
2.288
|
2.325
|
2.263
|
2-3/16
|
1.909
|
1.971
|
2.414
|
2.351
|
2.389
|
2.326
|
2-1/4
|
1.972
|
2.034
|
2.477
|
2.414
|
2.452
|
2.389
|
2-5/16
|
1.957
|
2.051
|
2.587
|
2.493
|
2.562
|
2.468
|
2-3/8
|
2.021
|
2.114
|
2.651
|
2.557
|
2.626
|
2.532
|
2-7/16
|
2.084
|
2.178
|
2.714
|
2.621
|
2.689
|
2.596
|
2-1/2
|
2.148
|
2.242
|
2.778
|
2.684
|
2.753
|
2.659
|
2-9/16
|
2.211
|
2.305
|
2.841
|
2.748
|
2.816
|
2.723
|
2-5/8
|
2.275
|
2.369
|
2.905
|
2.811
|
2.880
|
2.786
|
21-1/16
|
2.338
|
2.432
|
2.968
|
2.874
|
2.943
|
2.849
|
2-3/4
|
2.402
|
2.495
|
3.032
|
2.938
|
3.007
|
2.913
|
2-13/16
|
2.387
|
2.512
|
3.142
|
3.017
|
3.117
|
2.992
|
2-7/8
|
2.450
|
2.575
|
3.205
|
3.080
|
3.180
|
3.055
|
2-15/16
|
2.514
|
2.639
|
3.269
|
3.144
|
3.244
|
3.119
|
3
|
2.577
|
2.702
|
3.332
|
3.207
|
3.307
|
3.182
|
3-1/16
|
2.641
|
2.766
|
3.396
|
3.271
|
3.371
|
3.246
|
3-1/8
|
2.704
|
2.829
|
3.459
|
3.334
|
3.434
|
3.309
|
3-3/16
|
2.768
|
2.893
|
3.523
|
3.398
|
3.498
|
3.373
|
3-1/4
|
2.831
|
2.956
|
3.586
|
3.461
|
3.561
|
3.436
|
3-5/16
|
2.816
|
2.941
|
3.696
|
3.571
|
3.671
|
3.546
|
3-3/8
|
2.880
|
3.005
|
3.760
|
3.635
|
3.735
|
3.610
|
3-7/16
|
2.943
|
3.068
|
3.823
|
3.698
|
3.798
|
3.673
|
3-1/2
|
3.007
|
3.132
|
3.887
|
3.762
|
3.862
|
3.737
|
3-9/16
|
3.070
|
3.195
|
3.950
|
3.825
|
3.925
|
3.800
|
3-5/8
|
3.134
|
3.259
|
4.014
|
3.889
|
3.989
|
3.864
|
3-11/16
|
3.197
|
3.322
|
4.077
|
3.952
|
4.052
|
3.927
|
3-3/4
|
3.261
|
3.386
|
4.141
|
4.016
|
4.116
|
3.991
|
3-13/16
|
3.246
|
3.371
|
4.251
|
4.126
|
4.226
|
4.101
|
3-7/8
|
3.309
|
3.434
|
4.314
|
4.189
|
4.289
|
4.164
|
3-15/16
|
3.373
|
3.498
|
4.378
|
4.253
|
4.353
|
4.228
|
4
|
3.436
|
3.561
|
4.441
|
4.316
|
4.416
|
4.291
|
4-3/16
|
3.627
|
3.752
|
4.632
|
4.507
|
4.607
|
4.482
|
4-1/4
|
3.690
|
3.815
|
4.695
|
4.570
|
4.670
|
4.545
|
4-3/8
|
3.817
|
3.942
|
4.822
|
4.697
|
4.797
|
4.672
|
4-7/16
|
3.880
|
4.005
|
4.885
|
4.760
|
4.860
|
4.735
|
4-1/2
|
3.944
|
4.069
|
4.949
|
4.824
|
4.924
|
4.799
|
4-3/4
|
4.041
|
4.229
|
5.296
|
5.109
|
5.271
|
5.084
|
4-7/8
|
4.169
|
4.356
|
5.424
|
5.236
|
5.399
|
5.211
|
4-15/16
|
4.232
|
4.422
|
5.487
|
5.300
|
5.462
|
5.275
|
5
|
4.296
|
4.483
|
5.551
|
5.363
|
5.526
|
5.338
|
5-3/16
|
4.486
|
4.674
|
5.741
|
5.554
|
5.716
|
5.529
|
5-1/4
|
4.550
|
4.737
|
5.805
|
5.617
|
5.780
|
5.592
|
5-7/16
|
4.740
|
4.927
|
5.995
|
5.807
|
5.970
|
5.782
|
5-1/2
|
4.803
|
4.991
|
6.058
|
5.871
|
6.033
|
5.846
|
5-3/4
|
4.900
|
5.150
|
6.405
|
6.155
|
6.380
|
6.130
|
5-15/16
|
5.091
|
5.341
|
6.596
|
6.346
|
6.571
|
6.321
|
6
|
5.155
|
5.405
|
6.660
|
6.410
|
6.635
|
6.385
|
6-1/4
|
5.409
|
5.659
|
6.914
|
6.664
|
6.889
|
6.639
|
6-1/2
|
5.662
|
5.912
|
7.167
|
6.917
|
7.142
|
6.892
|
6-3/4
|
5.760
|
a5.885
|
7.515
|
a7.390
|
7.490
|
a7.365
|
7
|
6.014
|
a6.139
|
7.769
|
a7.644
|
7.744
|
a7.619
|
7-1/4
|
6.268
|
a6.393
|
8.023
|
a7.898
|
7.998
|
a7.873
|
7-1/2
|
6.521
|
a6.646
|
8.276
|
a8.151
|
8.251
|
a8.126
|
7-3/4
|
6.619
|
6.869
|
8.624
|
8.374
|
8.599
|
8.349
|
8
|
6.873
|
7.123
|
8.878
|
8.628
|
8.853
|
8.603
|
9
|
7.887
|
8.137
|
9.892
|
9.642
|
9.867
|
9.617
|
10
|
8.591
|
8.966
|
11.096
|
10.721
|
11.071
|
10.696
|
11
|
9.606
|
9.981
|
12.111
|
11.736
|
12.086
|
11.711
|
12
|
10.309
|
10.809
|
13.314
|
12.814
|
13.289
|
12.789
|
13
|
11.325
|
11.825
|
14.330
|
13.830
|
14.305
|
13.805
|
14
|
12.028
|
12.528
|
15.533
|
15.033
|
15.508
|
15.008
|
15
|
13.043
|
13.543
|
16.548
|
16.048
|
16.523
|
16.023
|
a 1-3/4 × 1-1/2 inch key.