ASTM A193 Grade B8M Standards

Hex Bolts ASME B18.2.1

Hex Bolts ASME B18.2.1

ASME B18.2.1 Hex Bolts

Dimensions of ASME B18.2.1 Hex Bolts

Nomianal Size or Basic product Diameter Full-Size Body Diameter, E Width Across Flats, F Width Across Corners, G Head Height, H Radius of Fillet, R Thread Length for Bolt Lengths, LT
6 in. & Shorter Over 6 in.
Max. Min. Basic Max. Min. Max. Min. Basic Max. Min. Max. Min. Nom. Nom.
1/4
0.2500
0.260 0.237 7/16 0.438 0.425 0.505 0.484 11/64 0.188 0.150 0.03 0.01 0.750 1.000
5/16
0.3125
0.324 0.298 1/2 0.500 0.484 0.577 0.552 7/32 0.235 0.195 0.03 0.01 0.875 1.125
3/8
0.3750
0.388 0.360 9/16 0.562 0.544 0.650 0.620 1/4 0.268 0.226 0.03 0.01 1.000 1.250
7/16
0.4375
0.452 0.421 5/8 0.625 0.603 0.722 0.687 19/64 0.316 0.272 0.03 0.01 1.125 1.375
1/2
0.5000
0.515 0.482 3/4 0.750 0.725 0.866 0.826 11/32 0.364 0.302 0.03 0.01 1.250 1.500
5/8
0.6250
0.642 0.605 15/16 0.938 0.906 1.083 1.033 27/64 0.444 0.378 0.06 0.02 1.500 1.750
3/4
0.7500
0.768 0.729 1 1/8 1.125 1.088 1.299 1.240 1/2 0.524 0.455 0.06 0.02 1.750 2.000
7/8
0.8750
0.895 0.852 1 5/16 1.312 1.269 1.516 1.447 37/64 0.604 0.531 0.06 0.02 2.000 2.250
1
1.0000
1.022 0.976 1 1/2 1.500 1.450 1.732 1.653 43/64 0.700 0.591 0.09 0.03 2.250 2.500
1 1/8
1.1250
1.149 1.098 1 11/16 1.688 1.631 1.949 1.859 3/4 0.780 0.658 0.09 0.03 2.500 2.750
1 1/4
1.2500
1.277 1.223 1 7/8 1.875 1.812 2.165 2.066 27/32 0.876 0.749 0.09 0.03 2.750 3.000
1 3/8
1.3750
1.404 1.345 2 1/16 2.062 1.994 2.382 2.273 29/32 0.940 0.810 0.09 0.03 3.000 3.250
1 1/2
1.5000
1.531 1.470 2 1/4 2.250 2.175 2.598 2.480 1/ 1.036 0.902 0.09 0.03 3.250 3.500
1 5/8
1.6250
1.658 1.591 2 7/16 2.438 2.356 2.815 2.616 1 3/32 1.116 0.978 0.09 0.03 3.500 3.750
1 3/4
1.7500
1.785 1.716 2 5/8 2.625 2.538 3.031 2.893 1 5/32 1.196 1.054 0.12 0.04 3.750 4.000
1 7/8
1.8750
1.912 1.839 2 13/16 2.812 2.719 3.248 3.099 1 1/4 1.276 1.130 0.12 0.04 4.000 4.250
2
2.000
2.039 1.964 3 3.000 2.9000 3.464 3.306 1 11/32 1.388 1.175 0.12 0.04 4.250 4.500
2 1/4
2.2500
2.305 2.214 3 3/8 3.375 3.262 3.897 3.719 1 1/2 1.548 1.327 0.19 0.06 4.750 5.000
2 1/2
2.5000
2.559 2.461 3 3/4 3.750 3.625 4.330 4.133 1 21/32 1.708 1.479 0.19 0.06 5.250 5.500
2 3/4
2.7500
2.827 2.711 4 1/8 4.125 3.988 4.763 4.546 1 13/16 1.869 1.632 0.19 0.06 5.750 6.000
3
3.000
3.081 2.961 4 1/2 4.500 4.350 5.196 4.959 2 2.060 1.815 0.19 0.06 6.250 6.500
3 1/4
3.2500
3.335 3.210 4 7/8 4.875 4.712 5.629 5.372 2 3/16 2.251 1.936 0.19 0.06 6.750 7.000
3 1/2
3.5000
3.589 3.461 5 1/4 5.250 5.075 6.062 5.786 2 5/16 2.380 2.057 0.19 0.06 7.250 7.500
3 3/4
3.7500
3.858 3.726 5 5/8 5.625 5.437 6.495 6.198 2 1/2 2.572 2.241 0.19 0.06 7.750 8.000
4
4.000
4.111 3.975 6 6.000 5.800 6.928 6.612 2 11/16 2.764 2.424 0.19 0.06 8.250 8.500