ASTM A194 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 | Tensile Class | Raw Material |
|---|---|---|
| B5 | 4-6% Chromium Ferritic Steel | |
| B6 | 13% Chromium Ferritic Steel | |
| B6X | 13% Chromium Ferritic Steel | |
| B7 | Chromium Molybdenum Alloy Steel, Quenched & Tempered | |
| B7M | Chromium Molybdenum Alloy Steel, Quenched & Tempered | |
| B16 | Chromium-molybdenum-vanadium Alloy Steel, Quenched & Tempered | |
| B8 | Class 1 | AISI 304 Stainless Steel, Carbide Solution Treated |
| B8 | Class 2 | AISI 304 Stainless Steel, Carbide Solution Treated and Strain Hardened |
| B8A | AISI 304 Stainless Steel, Carbide solution treated in the finished condition | |
| B8C | Class 1 | AISI 347 Stainless Steel, Carbide Solution Treated |
| B8C | Class 2 | AISI 347 Stainless Steel, Carbide Solution Treated and Strained Hardened |
| B8CA | AISI 347 Stainless Steel, Carbide Solution Treated in Finished Condition | |
| B8M | Class 1 | AISI 316 Stainless Steel, Carbide Solution Treated |
| B8M | Class 2 | AISI 316 Stainless Steel, Carbide Solution Treated and Strain Hardened |
| B8MA | AISI 316 Stainless Steel, Carbide Solution Treated in Finished Condition | |
| B8M2 | AISI 316 Stainless Steel, Carbide Solution Treated and Strain Hardened | |
| B8M3 | AISI 316 Stainless Steel, Carbide Solution Treated and Strain Hardened | |
| B8P | Class 1 | AISI 305 Stainless Steel, Carbide Solution Treated |
| B8P | Class 2 | AISI 305 Stainless Steel, Carbide Solution Treated and Strain Hardened |
| B8PA | AISI 305 Stainless Steel, Carbide Solution Treated in Finished Condition | |
| B8N | AISI 304N Stainless Steel, Carbide Solution Treated | |
| B8N | AISI 304N Stainless Steel, Carbide Solution Treated and Strain Hardened | |
| B8MLCuN | AISI 304N Stainless Steel, Carbide Solution Treated | |
| B8MLCuN | UNS S31254 Stainless Steel, Carbide Solution Treated and Strain Hardened | |
| B8MLCuNA | UNS S31254 Stainless Steel, Carbide Solution Treated | |
| B8T | Class 1 | AISI 321 Stainless Steel, Carbide Solution Treated |
| B8T | Class 2 | AISI 321 Stainless Steel, Carbide Solution Treated and Strain Hardened |
| B8TA | AISI 321 Stainless Steel, Carbide Solution Treated in Finished Condition | |
| B8R | Nitronic 50/UNS S20910 Stainless Steel, Carbide Solution Treated | |
| B8RA | Nitronic 50/UNS S20910 Stainless Steel, Carbide Solution Treated in Finished Condition | |
| B8S | Nitronic 60/UNS S21800 Stainless Steel, Carbide Solution Treated | |
| B8SA | Nitronic 60/UNS S21800 Stainless Steel, Carbide Solution Treated | |
| B8LN | AISI 304LN Stainless Steel, Carbide Solution Treated | |
| B8LNA | AISI 304LN Stainless Steel, Carbide Solution Treated in Finished Condition | |
| B8MLN | AISI 316LN Stainless Steel, Carbide Solution Treated | |
| B8MLNA | AISI 316LN Stainless Steel, Carbide Solution Treated in Finished Condition | |
| B8CLN | AISI 347LN Stainless Steel, Carbide Solution Treated | |
| B8CLNA | AISI 347LN Stainless Steel, Carbide Solution Treated in Finished Condition |
| Grade | Material | UNS Number |
C, % | Mn, % | Ph, % | S, % | Si, % | Cr, % | Ni, % | Mo, % | Ti, % | Cb & Ta, % | N, % | Other Elements, % |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | Carbon | 0.15 min | 1.000 | 0.040 | 0.050 | 0.400 | - | - | - | - | - | - | - | |
| 2, 2HM, & 2H | Carbon | 0.40 min | 1.000 | 0.040 | 0.050 | 0.400 | - | - | - | - | - | - | - | |
| 2H | Carbon | 0.40 min | 1.000 | 0.040 | 0.050 | 0.400 | - | - | - | - | - | - | - | |
| 2HM | Carbon | 0.40 min | 1.000 | 0.040 | 0.050 | 0.400 | - | - | - | - | - | - | - | |
| 3 | Type 501 | 0.10 min | 1.000 | 0.040 | 0.030 | 1.000 | 4.0-6.0 | - | 0.40-0.65 | - | - | - | - | |
| 4 | carbon, molybdenum |
0.40-0.50 | 0.70-0.90 | 0.035 | 0.040 | 0.15-0.35 | - | 0.20-0.30 | - | - | - | - | ||
| 6 | Type 410 | S41000 | 0.150 | 1.000 | 0.040 | 0.030 | 1.000 | 11.5-13.5 | - | - | - | - | - | - |
| 6F | Type 416 | S416000 | 0.150 | 1.250 | 0.060 | 0.15min | 1.000 | 12.0-14.0 | - | - | - | - | - | |
| 6F | Type 416Se | S41623 | 0.150 | 1.250 | 0.060 | 0.060 | 1.000 | 12.0-14.0 | - | - | - | - | Selenium, 0.15 min | |
| 7, 7M | Type 4140, 4142, 4145, 4140H, 4142H, 4145H | 0.37-0.49 | 0.65-1.10 | 0.035 | 0.040 | 0.15-0.35 | 0.75-1.2 | - | 0.15-0.25 | - | - | - | - | |
| 8 | Type 304 | S30400 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 18.0-20.0 | 8.0-11.0 | - | - | - | - | |
| 8A | Type 304 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 18.0-20.0 | 8.0-11.0 | - | - | - | - | ||
| 8C | Type 347 | S34700 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 17.0-19.0 | 9.0-12.0 | - | 10 x Carbon Content, min | - | - | |
| 8CA | Type 347 | S34700 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 17.0-19.0 | 9.0-12.0 | - | 10 x Carbon Content, min | - | - | |
| 8CLN, 8CLNA | Type 347LN | S34751 | 0.0005-0.020 | 2.000 | 0.045 | 0.030 | 1.000 | 17.0-19.0 | 9.0-13.0 | - | 0.20-0.50, 15 x Carbon Content,min | 0.06-0.10 | - | |
| 8M, 8MA | Type 316 | S31600 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 16.0-18.0 | 10.0-14.0 | 2.00-3.00 | - | - | - | - |
| 8T, 8TA | Type 321 | S32100 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 17.0-19.0 | 9.0-12.0 | - | 5 x (C+N),Min – 0.70 max | - | 0.100 | - |
| 8F, 8FA | Type 303 | S30300 | 0.150 | 2.000 | 0.200 | 0.150 | 1.000 | 17.0-19.0 | 8.0-10.0 | - | - | - | - | - |
| 8F, 8FA | Type 303 Se | S30323 | 0.150 | 2.000 | 0.200 | 0.06 | 1.000 | 17.0-19.0 | 8.0-10.0 | - | - | - | - | Selenium, 0.15 min |
| 8P, 8PA | Type 305 with restricted carbon | S30500 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 17.0-19.0 | 11.0-13.0 | - | - | - | - | - |
| 8N, 8NA | Type 304N | S30451 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 18.0-20.0 | 8.0-11.0 | - | - | - | 0.10-0.16 | - |
| 8LN, 8LNA | 0.030 | 2.000 | 0.045 | 0.030 | 1.000 | 18.0-20.0 | 8.0-11.0 | - | - | - | 0.10-0.16 | - | ||
| 8MN, 8MNA | Type 316N | S31651 | 0.080 | 2.000 | 0.045 | 0.030 | 1.000 | 16.0-18.0 | 10.0-13.0 | 2.0-3.0 | - | - | 0.10-0.16 | - |
| 8MLN, 8MLNA | Type 316LN | S31653 | 0.030 | 2.000 | 0.045 | 0.030 | 1.000 | 16.0-18.0 | 10.0-13.0 | 2.0-3.0 | - | - | 0.10-0.16 | - |
| 8R, 8RA | XM19 | S20910 | 0.060 | 4.0-6.0 | 0.045 | 0.030 | 1.000 | 20.5-23.5 | 11.5-13.5 | 1.50-3.0 | - | 0.10-0.30 | 0.20-0.40 | Vanadium, 0.10-0.30 |
| 8S, 8SA | S21800 | 0.100 | 7.0-9.0 | 0.060 | 0.030 | 3.5-4.5 | 16.0-18.0 | 8.0-9.0 | - | - | - | 0.08-0.18 | - | |
| 8MLCuN, 8MLCuNA | S31254 | S31254 | 0.020 | 1.000 | 0.030 | 0.010 | 0.800 | 19.5-20.5 | 17.5-18.5 | 6.0-6.5 | - | - | 0.18-0.25 | Copper 0.50-1.00 |
| 9C, 9CA | N08367 | N08367 | 0.030 | 2.000 | 0.040 | 0.030 | 1.000 | 20.0-22.0 | 23.5-25.5 | 6.0-7.0 | - | - | 0.18-0.25 | Copper 0.75 |
| 16 | Chromium Molybdenum Vanadium | 0.36-0.47 | 0.45-0.70 | 0.035 | 0.040 | 0.15-0.35 | 0.80-1.15 | 0.50-0.65 | - | - | - | Vanadium 0.25-0.35 AluminumB 0.015 |
| Grade & Type | Brinell Hardness | Rockwell Hardness | |
|---|---|---|---|
| C Scale | B Scale | ||
| 2 | 159-352 | - | 84 min |
| 2H | 248-327 | 24-35 | - |
| 2H | 212-327 | 35 max | 95 min |
| 2HM and 7M | 159-235 | - | 84 - 99 |
| 4, 7, 16 | 248-327 | 24 - 35 | - |
| 6 and 6F | 225-271 | 20-28 | - |
| 8, 8C, 8M, 8T, 8F, 8MLCuN | 126-300 | 32 max | 60 min |
| 8A, 8CA, 8MA, 8TA, 8MLCuNA | 126-192 | - | 60 – 90 |
| 8R, 8RA, 8S. 8SA | 183-271 | 25 max | 88 min |
| Nominal Size, inch | Threads per inch | Stress Area inch | Proof Load, lbf | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| GRADE 2, 2HM, 6, 6f, 7M | Grade 2H, 4, 7, 16 | All Types of Grade 8 | ||||||||
| Heavy Hex | Hex | Heavy Hex | Hex | Heavy Hex | Hex | |||||
| 1/4" | 20 | 0.0316 | 4130 | 3820 | 4770 | 4300 | 5570 | 4770 | ||
| 5/16" | 18 | 0.0524 | 6810 | 6290 | 7860 | 7070 | 9170 | 7860 | ||
| 3/8" | 16 | 0.0774 | 10080 | 9300 | 11620 | 10460 | 13560 | 11620 | ||
| 7/16" | 14 | 0.1063 | 13820 | 12760 | 15940 | 14350 | 18600 | 15940 | ||
| 1/2" | 13 | 0.1419 | 18450 | 17030 | 21280 | 19160 | 24830 | 21280 | ||
| 9/16" | 12 | 0.1820 | 23660 | 21840 | 27300 | 24570 | 31850 | 27300 | ||
| 5/8" | 11 | 0.2260 | 29380 | 27120 | 33900 | 30510 | 39550 | 33900 | ||
| 3/4" | 10 | 0.3340 | 43420 | 40080 | 50100 | 45090 | 58450 | 50100 | ||
| 7/8" | 9 | 0.4620 | 60060 | 55440 | 69300 | 62370 | 80850 | 69300 | ||
| 1" | 8 | 0.606 | 78780 | 72720 | 90900 | 81810 | 106000 | 90900 | ||
| 1 1/8" | 8 | 0.7900 | 102700 | 94800 | 118500 | 106700 | 138200 | 118500 | ||
| 1 1/4" | 8 | 1.0000 | 130000 | 120000 | 150000 | 135000 | 175000 | 150000 | ||
| 1 3/8" | 8 | 1.2330 | 160200 | 148000 | 185000 | 166500 | 215800 | 185000 | ||
| 1 1/2" | 8 | 1.492 | 194000 | 170040 | 223800 | 201400 | 261100 | 223800 | ||
| Grade Type | Hot Forged or Cold Punched Nuts | Nuts Machined from Bar Stock |
|---|---|---|
| 2 | 2 | 2B |
| 2H | 2H | 2HB |
| 2HM | 2HM | 2HMB |
| 4 | 4 | 4B |
| 6 | 6 | 6B |
| 6F | 6F | 6FB |
| 7 | 7 | 7B |
| 7M | 7M | 7MB |
| 7L | 7L | 7LB |
| 8 | 8 | 8B |
| 8M | 8M | 8MB |
| 8C | 8C | 8CB |
| 8T | 8T | 8TB |
| 8F | 8F | 8FB |
| 8R | 8R | 8RB |
| 8S | 8S | 8SB |
| 8MLCuN | 8MLCuN | 8MLCuNB |
| 16 | 16 | 16B |