



Heavy Hex Nuts
Heavy hex nuts are the strongest of all nut designs in their class. Our heavy hex nuts are manufactured in accordance with ASTM B18.2.2 standards.
- Material: Carbon Steel, Stainless steel, Copper
- Type: Hexagon sharp
- Thread Size: 1/4 inch to 4 inch
- Surface Finish: Plain, Black Oxidated, Zinc Plating, Yellow Plating, H.D.G
- Class: Grade 2, Grade 5, A194 2H, A563 A,B,C&D
- Production Tech: Cold Forming, hot Forming
- Packing: Small box, 25kgs bulk package
Heavy Hexagon Nut details
Heavy hex nuts are thicker and wider than the (finished) hex nuts of the same size, making them the strongest nut in their class. Its extra strength comes from the greater hooking of the thread, which is due to its thickness and its greater resistance to expansion (expansion or stretching) due to its greater width.
The increase in the size of the heavy hex nut produces a larger bearing surface and improved wrench capacity. Hex is an abbreviation for hexagon, meaning that they have six sides.

Hex nuts UNC or UNF
The thread is the standard right side series and unified inch coarse pitch (UNC, unified national coarse pitch) or unified imperial fine pitch (UNF, unified national fine pitch). Left-threaded heavy hex nuts are also available.
Heavy hex nuts are used in various industrial applications. They are used to construct bridges, buildings, wind turbines, ships, and various other applications.
Heavy Hex Nuts B18.2.2 Dimensions

Nominal Size or Basic Major Thread Diameter | F | G | H | ||||||
Width Across Flats | Width Across Corners | Thickness | |||||||
Basic | Max | Min | Max | Min | Basic | Max | Min | ||
1/4″ | 0.250 | 1/2″ | 0.500 | 0.488 | 0.577 | 0.556 | 15/64″ | 0.250 | 0.218 |
5/6″ | 0.313 | 9/16″ | 0.562 | 0.546 | 0.650 | 0.622 | 19/64″ | 0.314 | 0.280 |
3/8″ | 0.375 | 11/16″ | 0.688 | 0.669 | 0.794 | 0.763 | 23/64″ | 0.377 | 0.341 |
7/16″ | 0.438 | 3/4″ | 0.750 | 0.728 | 0.866 | 0.830 | 27/64″ | 0.441 | 0.403 |
1/2″ | 0.500 | 7/8″ | 0.875 | 0.850 | 1.010 | 0.969 | 31/64″ | 0.504 | 0.464 |
9/16″ | 0.563 | 15/16″ | 0.938 | 0.909 | 1.083 | 1.037 | 35/64″ | 0.568 | 0.526 |
5/8″ | 0.625 | 1-1/16″ | 1.062 | 1.031 | 1.227 | 1.175 | 39/64″ | 0.631 | 0.587 |
3/4″ | 0.750 | 1-1/4“ | 1.250 | 1.212 | 1.443 | 1.382 | 47/64″ | 0.758 | 0.710 |
7/8″ | 0.875 | 1-7/16″ | 1.438 | 1.394 | 1.660 | 1.589 | 55/64″ | 0.885 | 0.833 |
1″ | 1.000 | 1-5/8″ | 1.625 | 1.575 | 1.876 | 1.796 | 63/64″ | 1.012 | 0.956 |
1-1/8″ | 1.125 | 1-13/16″ | 1.812 | 1.756 | 2.093 | 2.002 | 1-7/64″ | 1.139 | 1.079 |
1-1/4″ | 1.250 | 2″ | 2.000 | 1.938 | 2.309 | 2.209 | 1-7/32″ | 1.251 | 1.187 |
1-3/8″ | 1.375 | 2-3/16″ | 2.188 | 2.119 | 2.526 | 2.416 | 1-11/32″ | 1.378 | 1.310 |
1-1/2″ | 1.500 | 2-3/8″ | 2.375 | 2.300 | 2.742 | 2.622 | 1-15/32″ | 1.505 | 1.433 |
1-5/8″ | 1.625 | 2-9/16″ | 2.562 | 2.481 | 2.959 | 2.828 | 1-19/32″ | 1.632 | 1.556 |
1-3/4′ | 1.750 | 2-3/4″ | 2.750 | 2.662 | 3.175 | 3.035 | 1-23/32″ | 1.759 | 1.679 |
2″ | 2.000 | 3-1/8″ | 3.125 | 3.025 | 3.608 | 3.449 | 1-31/32″ | 2.013 | 1.925 |
2-1/4″ | 2.250 | 3-1/2″ | 3.500 | 3.388 | 4.041 | 3.862 | 2-13/64″ | 2.251 | 2.155 |
2-1/2″ | 2.500 | 3-7/8″ | 3.875 | 3.750 | 4.474 | 4.275 | 2-29/64″ | 2.505 | 2.401 |
2-3/4″ | 2.750 | 4-1/4″ | 4.250 | 4.112 | 4.907 | 4.688 | 2-45/64″ | 2.759 | 2.647 |
3″ | 3.000 | 4-5/8″ | 4.625 | 4.475 | 5.340 | 5.102 | 2-61/64″ | 3.013 | 2.893 |
3-1/4″ | 3.250 | 5″ | 5.000 | 4.838 | 5.774 | 5.515 | 3-3/16″ | 3.252 | 3.124 |
3-1/2″ | 3.500 | 5-3/8″ | 5.375 | 5.200 | 6.207 | 5.928 | 3-7/16″ | 3.506 | 3.370 |
3-3/4″ | 3.750 | 5-3/4″ | 5.750 | 5.562 | 6.640 | 6.341 | 3-11/16″ | 3.670 | 3.616 |
4″ | 4.000 | 6-1-8″ | 6.125 | 5.925 | 7.073 | 6.755 | 3-15/16″ | 4.014 | 3.862 |