Skip to main content

7/8-9 A194 Grade 2Hm Heavy Hex Nut

Selected A194 2HM Heav Hex Nut Black Oxide2HM Heavy Hex Nut
A194 2HM Heav Hex Nut Black Oxide2HM Heavy Hex Nut

Product Specification

Grade
Grade 2HM
Finish
Black
Weight
0.297000
Diameter
7/8

Governing Standards

ASTM A194 This specification covers a variety of carbon, alloy, and martensitic stainless steel nuts in the size range 1⁄4 through 4 in. and metric M6 through M100 nominal. It also covers austenitic stainless steel nuts in the size range 1⁄4 in. and M6 nominal and above. These nuts are intended for high-pressure or high temperature service, or both. Grade substitutions without the purchaser’s permission are not allowed.
ASME B18.2.2 Covers the complete general and dimensional data for the various types of inch series square and hex nuts, including machine screw nuts and coupling nuts.
ASME B1.1 UNC & UNF Class 2B Specifies the thread form, series, class, allowance, tolerance, and designation for unified screw threads.

Grade 2HM Head Marking
Grade 2HM Material Marking

Chemical Properties

Per ASTM A194/A194M-16
Grade Material Carbon Manganese Phosphorus Sulfur (1) Silicon
% by weight % by weight % by weight % by weight % by weight
2HM Carbon Steel 0.40 min 1.00 max 0.040 max 0.050 max 0.04 max
  1. 1. Because of the degree to which sulfur segregates, product analysis for sulfur over 0.060 % max is not technologically appropriate.

Mechanical Properties

Carbon Steel, Quenched & Tempered, 100% Hardness Tested Per ASTM A194/A194M-16
Proof Load Stress (psi) min Hardness Hardness Tempering Temperature
Min psi Brinell Rockwell (B Scale) Min
150,000 159 to 235 84 to 99 1150F
150,000 159 to 235 84 to 99 1150F

Dimensional Specifications

Heavy hex nut dimensions
Per ASME B18.2.2-2015
Nominal Diameter UNC UN8 F G H
Width Across Flats Width Across Corners Thickness
Basic Max Min Max Min Basic Max Min
1/4 0.250 20   1/2 0.500 0.488 0.577 0.556 15/64 0.250 0.218
5/16 0.313 18   9/16 0.562 0.546 0.650 0.220 19/64 0.314 0.280
3/8 0.375 16   11/16 0.688 0.669 0.794 0.763 23/64 0.377 0.341
7/16 0.438 14   3/4 0.750 0.728 0.866 0.830 27/64 0.441 0.403
1/2 0.500 13   7/8 0.875 0.850 1.010 0.990 31/64 0.504 0.464
9/16 0.563 12   15/16 0.938 0.909 1.083 1.037 35/64 0.568 0.526
5/8 0.625 11   1 1/16 1.062 1.031 1.227 1.175 39/64 0.631 0.587
3/4 0.750 10   1 1/4 1.250 1.212 1.443 1.382 47/64 0.758 0.710
7/8 0.875 9   1 7/16 1.438 1.394 1.660 1.589 55/64 0.885 0.833
1 1.000 8   1 5/8 1.625 1.575 1.876 1.796 63/64 1.012 0.956
1 1/8 1.125 7 8 1 13/16 1.812 1.756 2.093 2.002 1 7/64 1.139 1.079
1 1/4 1.250 7 8 2 2.000 1.380 2.309 2.209 1 7/32 1.251 1.187
1 3/8 1.375 6 8 2 3/16 2.188 2.119 2.526 2.416 1 11/32 1.378 1.310
1 1/2 1.500 6 8 2 3/8 2.375 2.300 2.742 2.622 1 15/32 1.505 1.433
1 5/8 1.625 5 1/2 8 2 9/16 2.562 2.481 2.959 2.828 1 19/32 1.632 1.556
1 3/4 1.750 5 8 2 3/4 2.750 2.662 3.175 3.035 1 23/32 1.759 1.679
1 7/8 1.875 5 8 2 15/16 2.938 2.844 3.392 3.242 1 27/32 1.886 1.802
2 2.000 4 1/2 8 3 1/8 3.125 3.025 3.608 3.449 1 31/32 2.013 1.925
2 1/4 2.250 4 1/2 8 3 1/2 3.500 3.388 4.041 3.862 2 13/64 2.251 2.155
2 1/2 2.500 4 8 3 7/8 3.875 3.750 4.474 4.275 2 29/64 2.505 2.401
2 3/4 2.750 4 8 4 1/4 4.250 4.112 4.907 4.688 2 45/64 2.759 2.647
3 3.000 4 8 4 5/8 4.625 4.475 5.340 5.102 2 61/64 3.013 2.893
3 1/4 3.250 4 8 5 5.000 4.838 5.774 5.515 3 3/16 3.252 3.124
3 1/2 3.500 4 8 5 3/8 5.375 5.200 6.207 5.928 3 7/16 3.506 3.370
3 3/4 3.750 4 8 5 3/4 5.750 5.562 5.562 6.341 3 11/16 3.670 3.616
4 4.000 4 8 6 1/8 6.125 5.925 5.925 6.755 3 15/16 4.014 3.862
  1. All dimensions are in inches.
Loading product details...