China Manufacturer of Stud Bolt ASTM A193 Gr B8m Cl2/A194 Gr 8mA with 2 Heavy Hex Nuts Dims to ASME B18.2.1 B18.2.2 Threaded to ASME B1.1 Cl 2A/2b Unc stud bolt.
ASTM A193 Gr B8M stud bolt is made of round bar AISI 316L with carbide solution treated and strain hardened
Astm A193 Grade B8M Class 2 Stud Bolts / ASTM A193 Grade B8M Class 2 Fasteners
- ASTM A193 B8M is often available in national coarse (UNC) thread pitches,
- if being used in traditional applications, threads are specified 8 threads
- per inch (tpi) for diameters above one inch.
- ASTM A193, Grade B8M Class 1 Stainless steel, AISI 316, carbide solution treated.
- Stainless steel, AISI 316, carbide solution treated.
- ASTM A193, Grade B8 Class 2 Stainless steel, AISI 316, carbide solution treated,strain hardened.
1.ASTM A193 B8M raw material chemical composition
| Element | B8M (AISI 316) |
| Carbon | 0.08% max |
| Manganese | 2.00% max |
| Phosphorus, max | 0.05% |
| Sulfur, max | 0.03% |
| Silicon | 1.00% max |
| Chromium | 16.0 – 18.0% |
| Nickel | 10.0 – 14.0% |
| Molybdenum | 2.00 – 3.00% |
2.ASTM A193 B8M properties
| Grade and Class | Diameter | Tensile Strength Min KSI | Yield Strength 0.2% Offset KSI | Elongation in 2in. Min, % | Reduction of Area Min, % | Hardness max |
| CLASS 1: B8, B8C, B8M, B8P, B8F, B8T, B8LN, B8MLN | ALL | 75 | 30 | 30 | 50 | 223 HB or 96 HRB |
| CLASS 1A: B8A, B8CA, B8MA, B8PA, B8FA, B8TA, B8LNA, B8MLNA | ALL | 75 | 30 | 30 | 50 | 192 HB or 90 HRB |
| CLASS 2: B8, B8C, B8P, B8F, B8T | 3/4″ and under | 125 | 100 | 12 | 35 | 321 HB or 35 HRC |
| over 3/4 to 1″ incl | 115 | 80 | 15 | 30 | 321 HB or 35 HRC | |
| over 1″ to 1-1/4″ incl | 105 | 65 | 20 | 35 | 321 HB or 35 HRC | |
| over 1-1/4″ to 1-1/2″ | 100 | 50 | 28 | 45 | 321 HB or 35 HRC | |
| CLASS 2: B8M | 3/4″ and under | 110 | 95 | 15 | 45 | 321 HB or 35 HRC |
| over 3/4 to 1″ incl | 100 | 80 | 20 | 45 | 321 HB or 35 HRC | |
| over 1″ to 1-1/4″ incl | 95 | 65 | 25 | 45 | 321 HB or 35 HRC | |
| over 1-1/4″ to 1-1/2″ | 90 | 50 | 30 | 45 | 321 HB or 35 HRC |
3.ASTM A193 Grade B8M Class 2 Stud Bolt Sizes Range 1/2” to 4”
ASTM A193 Grade B8M Class 2 Stud Bolt heat Treatment
ASTM A193 Grade B8M Class 2 is a carbide solution treated and strain hardened
ASTM A193 Grade B8M Hardness
316/316L stainless steel bolting material specification, with higher tensile strength requirement of 125 ksi or 860 MPa and 100 ksi or 690 MPa and maximum hardness of 321 HBW or 35HRC. B8M Class 2 fasteners have higher tensile as compared to B8M Class 1 fasteners and are used for high strength bolting intended for high temperature or high-pressure applications.
HEX NUTS FOR ASTM A193 Grade B8M
A194 Grade 8MA