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, % |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
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 |
Grade & Type |
Brinell Hardness |
Rockwell Hardness |
|
|---|---|---|---|
C Scale |
B Scale |
||
8RA |
183-271 |
25 max |
88 min |
Nominal Size, inch |
Threads per inch |
Stress Area inch |
Proof Load, lbf |
|
|---|---|---|---|---|
All Types of Grade 8 |
||||
Heavy Hex |
Hex |
|||
1/4" |
20 |
0.0316 |
5570 |
4770 |
5/16" |
18 |
0.0524 |
9170 |
7860 |
3/8" |
16 |
0.0774 |
13560 |
11620 |
7/16" |
14 |
0.1063 |
18600 |
15940 |
1/2" |
13 |
0.1419 |
24830 |
21280 |
9/16" |
12 |
0.1820 |
31850 |
27300 |
5/8" |
11 |
0.2260 |
39550 |
33900 |
3/4" |
10 |
0.3340 |
58450 |
50100 |
7/8" |
9 |
0.4620 |
80850 |
69300 |
1" |
8 |
0.606 |
106000 |
90900 |
1 1/8" |
8 |
0.7900 |
138200 |
118500 |
1 1/4" |
8 |
1.0000 |
175000 |
150000 |
1 3/8" |
8 |
1.2330 |
215800 |
185000 |
1 1/2" |
8 |
1.492 |
261100 |
223800 |
| Grade Type | Hot Forged or Cold Punched Nuts | Nuts Machined from Bar Stock |
|---|---|---|
| 8 | 8 | 8B |