ASME B18.3 Hexagon Socket Flat Head Cap Screws

ASME B18.3 Hexagon Socket Flat Head Cap Screws

ASME B18.3 Hexagon Socket Flat Head Cap Screws Dimensions

ASME B18.3 Hexagon Socket Flat Head Cap Screws Dimensions

Nominal Size or Basic Screw DiameterBody Diameter, DHead Diameter, AHead Height, HHexagon Socket SizeKey Engagement, T
MaxMinTheo. Sharp MaxAbs MinRefNomMin
00.06000.06000.05680.1380.1170.0440.0350.025
10.07300.07300.06950.1680.1430.0540.0500.031
20.08600.08600.08220.1970.1680.0640.0500.038
30.09900.09900.09490.2260.1930.0731/160.044
40.11200.11200.10750.2550.2180.0831/160.055
50.12500.12500.12020.2810.2400.0905/640.061
60.13800.13800.13290.3070.2630.0975/640.066
80.16400.16400.15850.3590.3110.1123/320.076
100.19000.19000.18400.4110.3590.1271/80.087
1/40.25000.25000.24350.5310.4800.1615/320.111
5/160.31250.31250.30530.6560.6000.1983/160.135
3/80.37500.37500.36780.7810.7200.2347/320.159
7/160.43750.43750.42940.8440.7810.2341/40.159
1/20.50000.50000.49190.9380.8720.2515/160.172
5/80.62500.62500.61631.1881.1120.3243/80.220
3/40.75000.75000.74061.4381.3550.3961/20.220
7/80.87500.87500.86471.6881.6040.4689/160.248
11.00001.00000.98861.9381.8410.5405/80.297
1 1/81.12501.12501.10862.1882.0790.6113/40.325
1 1/41.25001.25001.23362.4382.3160.6837/80.358
1 3/81.37501.37501.35682.6882.5530.7557/80.402
1 1/21.50001.50001.48182.9382.7910.82710.435

Length Tolerances for Screws

Nomianal LengthNominal Size
1/4 to 3/87/16 and 1/29/16 to 3/47/8 to 11 1/8 to 1 1/2Over 1 1/2
Up to 1 in., incl.+0.00
-0.03
+0.00
-0.03
+0.00
-0.03
...
...
...
...
...
...
Over 1 in. to 2 1/2 in., incl.+0.00
-0.04
+0.00
-0.06
+0.00
-0.08
+0.00
-0.10
+0.00
-0.12
+0.00
-0.18
Over 2 1/2 in. to 4 in., incl.+0.00
-0.06
+0.00
-0.08
+0.00
-0.010
+0.00
-0.14
+0.00
-0.16
+0.00
-0.20
Over 4 in. to 6 in., incl.+0.00
-0.10
+0.00
-0.10
+0.00
-0.10
+0.00
-0.16
+0.00
-0.18
+0.00
-0.22
Longer than 6 in.+0.00
-0.18
+0.00
-0.18
+0.00
-0.18
+0.00
-0.20
+0.00
-0.22
+0.00
-0.24

ASTM A193 Grade B7 Fastener Coatings