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Date Published:Jun. 18. 2015 Date Updated:Jul. 28. 2022

Hexalobular Internal Driving Feature for Bolts and Screws

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Hexalobular Internal Driving Feature for Bolts and Screws

Shape and dimensions of hexalobular socket for bolt and screw

Note(1)The allowable depth f of broad mouth part is according to the table.

Unit : mm

Hexalobular socket No. 3 4 5 6 8 10 15 20 25 30 40 45 50
Nominal dimension(2) A 1.2 1.35 1.5 1.75 2.4 2.8 3.35 3.95 4.5 5.6 6.75 7.93 8.95
B 0.85 1.0 1.1 1.27 1.75 2.05 2.4 2.85 3.25 4.05 4.85 5.64 6.45
Allowable depth f of the mouth broad part 0.114 0.13 0.22 0.35 0.48 0.56 0.67 0.79 0.90 1.12 1.18 1.39 1.56
Allowable limit dimensions of
go-side gauge
A Max/Min 1.145
1.131
1.305
1.291
1.430
1.415
1.709
1.695
2.349
2.335
2.776
2.761
3.309
3.295
3.893
3.879
4.465
4.451
5.557
5.543
6.687
6.673
7.856
7.841
8.872
8.857
B Max/Min
0.815
0.800
0.927
0.912
1.028
1.013
1.224
1.210
1.686
1.672
1.993
1.979
2.367
2.353
2.778
2.764
3.185
3.170
3.972
3.958
4.780
4.766
5.570
5.555
6.380
6.366
Gi Max/Min
0.270
0.263
0.312
0.305
0.342
0.318
0.396
0.371
0.523
0.498
0.609
0.585
0.728
0.704
0.871
0.846
0.932
0.907
1.206
1.182
1.440
1.415
1.808
1.784
1.828
1.804
Ge Max/Min
0.085
0.078
0.093
0.087
0.111
0.107
0.134
0.130
0.193
0.188
0.231
0.227
0.269
0.265
0.307
0.303
0.378
0.371
0.454
0.448
0.548
0.544
0.576
0.572
0.777
0.773
Allowable limit dimensions of
not-go side gauge
A Max/Min
1.222
1.214
1.382
1.374
1.506
1.499
1.785
1.778
2.425
2.419
2.852
2.845
3.385
3.379
3.970
3.963
4.566
4.560
5.659
5.652
6.814
6.807
7.983
7.976
8.999
8.992
B Max
0.790 0.917 1.044 1.181 1.664 1.956 1.956 2.616 2.868 3.886 4.661 4.661 6.413
Gi Max/Min
0.145
0.137
0.191
0.180
0.221
0.208
0.241
0.231
0.370
0.360
0.441
0.431
0.408
0.398
0.614
0.602
0.647
0.637
0.949
0.939
1.125
1.112
1.123
1.110
1.640
1.628
Ge Max/Min
0.130
0.119
0.140
0.132
0.157
0.147
0.180
0.173
0.238
0.231
0.276
0.269
0.315
0.307
0.353
0.345
0.436
0.429
0.513
0.505
0.619
0.612
0.648
0.640
0.848
0.840
Allowable limit dimensions of
not-go side cylindrical gauge
for the dimension B
Max/Min
0.965
0.960
1.105
1.100
1.205
1.200
1.445
1.440
1.925
1.920
2.285
2.280
2.765
2.760
3.285
3.280
3.725
3.720
4.665
4.660
5.605
5.600
6.665
6.660
7.385
7.380

Note(2)The curve of hexalobular socket contour is determined by the gauge specified in the above table.

Remarks:

  1. The bore depth c shall be 0.13 mm or smaller for hole No. 15 or smaller and 0.25 mm or smaller for hole over No. 15.
  2. Sink depth t depends on respective product standard.
  3. It is at the discretion of manufacturer as long as the hole bottom shape satisfies the allowable limit of sink depth t.
  4. Hexalobular socket must be able to accept the go-side gauge down to the sink depth t specified by the applicable product standard without effort.
  5. The not-go side gauge must be beyond the allowable depth f of the broad mouth part specified in the table.


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