Grade 8 SS Heavy Hex Nut Domestic
Choose Favorites List

Grade 8 SS Heavy Hex Nut Domestic

Domestic ASTM A194 Grade 8 heavy hex nuts are manufactured from AISI 304 grade stainless steel, tested to meet ASTM A194 Grade 8, and are melted and manufactured in the USA. Dimensional specifications are governed by ASME B18.2.2. Grade markings for A194 Grade 8 heavy hex nuts consists of the number 8. Grade 8 stainless steel heavy hex nuts are intended for use in high-pressure and/or high-temperature service with ASTM A193 bolting of similar material, such as B8 and B8 Class 2. Heavy hex nuts provide increased bearing surface area over finished nuts.

Governing StandardsGrade 8 Stainless Steel

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 8 Stainless Steel Head Marking
Grade 8 Stainless Steel Material Marking

Mechanical PropertiesGrade 8 Stainless Steel

Stainless AISI 304 Per ASTM A194/A194M-16
Diameter Proof Load Stress Core Hardness
Min psi Rockwell
1/4" thru 4" 80,000 C32 max

Chemical PropertiesGrade 8 Stainless Steel

Per ASTM A194/A194M-16
Grade Material Carbon Manganese Phosphorus Sulfur (1) Silicon Chromium Nickel
% by weight % by weight % by weight % by weight % by weight % by weight % by weight
8 Type 304 Stainless Steel 0.08 max 2.00 max 0.045 max 0.030 max 1.00 max 18.0-20.0 8.0-11.0
  1. 1. Because of the degree to which sulfur segregates, product analysis for sulfur over 0.060 % max is not technologically appropriate.

Dimensional SpecificationsGrade 8 Stainless Steel

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 0.250 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.
Grade 8 SS Heavy Hex Nut Domestic
View
Diameter Thread Pitch Width Across Flats Height of Nut Item # Availability Price Quantity UOM
1/2 13 7/8 0.4844 NHB80500000-U In Stock $2.51248/EA EA
5/8 11 1 1/16 0.6094 NHB80620000-U In Stock $5.96658/EA EA
3/4 10 1 1/4 0.7344 NHB80750000-U 3-5 Working Days $7.52644/EA EA
7/8 9 1 7/16 0.8594 NHB80870000-U In Stock $20.8914/EA EA
1 8 1 5/8 0.9844 NHB81000000-U 3-5 Working Days $24.17156/EA EA