A194 Heavy Hex Nuts Dimensions

Thread Diameter Dimension F Dimension H Nut Weight
Min [inch] Max [inch] Min [inch] Max [inch] kg
1/4" 0.488 0.5 0.218 0.25 0.01
5/16" 0.546 0.562 0.28 0.314 0.01
3/8" 0.669 0.688 0.341 0.377 0.01
7/16" 0.728 0.75 0.403 0.441 0.02
1/2" 0.85 0.875 0.464 0.504 0.03
9/16" 0.909 0.938 0.526 0.568 0.04
5/8" 1.031 1.062 0.587 0.631 0.05
3/4" 1.212 1.25 0.71 0.758 0.09
7/8" 1.394 1.438 0.833 0.885 0.13
1" 1.575 1.625 0.956 1.012 0.19
1 1/8" 1.756 1.812 1.079 1.139 0.26
1 1/4" 1.938 2 1.187 1.251 0.37
1 3/8" 2.119 2.188 1.31 1.378 0.48
1 1/2" 2.3 2.375 1.433 1.505 0.58
1 5/8" 2.481 2.562 1.556 1.632 0.78
1 3/4" 2.662 2.75 1.679 1.759 0.96
1 7/8" 2.844 2.938 1.802 1.866 1.16
2"  3.025 3.125 1.925 2.013 1.4
2 1/4"  3.388 3.5 2.155 2.251 1.9
2 1/2"  3.75 3.875 2.401 2.505 2.56
2 3/4"  4.112 4.25 2.647 2.75 3.35
3"  4.475 4.625 2.893 3.013 4.32

Grade symbol marking of Heavy Hex Nuts

These grades shall be uniformly reheated to proper austenitising temperatures and be liquid quenched and tempered under substantially uniform conditions.

The H and M indicate heat-treated nuts.

An underline as a marking requirement for grades 2HM and 7M has been removed but is permitted.

*Manufactured in accordance with 6.6 nuts shall subsequently be carbide-solution treated by heating them for a sufficient time at a temperature to dissolve chromium carbides followed by cooling at a rate sufficient to prevent re-precipitation of the carbides.

Grade & Type Hot-forged or cold-punched Machined from bar stock See*
2H 2H 2HB -
2HM 2HM 2HMB -
3 3 3B -
4 4 4B -
6 6 6 -
7 7 7B -
7M 7M 7M -
8 8 8B -
8C 8C 8CB -
8M 8M 8MB 8MA
8T 8T 8TB -