ASTM A193
The A193 specification is often used in petroleum and chemical construction industry for alloy steel and stainless steel bolting materials for high temperature or high pressure service. The A193 specification includes fasteners intended for use in valves, flanges, fittings, and many other applications.
Grades
| B7 | AISI 4140/4142 Quenched and tempered |
|---|---|
| B8 Class 1 | AISI 304, carbide solution treated |
| B8 Class 2 | AISI 304, carbide solution treated, strain hardened |
| B8M Class 1 | AISI 316, carbide solution treated |
| B8M Class 2 | AISI 316, carbide solution treated, strain hardened |
Mechanical Properties
| Grade | Size | Tensile ksi, min | Yield, ksi, min | Elong, %, min | RA % min |
|---|---|---|---|---|---|
| B7 | Up to 2-1/2 | 125 | 105 | 16 | 50 |
| 2-5/8 - 4 | 115 | 95 | 16 | 50 | |
| 4-1/8 - 7 | 100 | 75 | 18 | 50 | |
| B8 Class 1 | All | 75 | 30 | 30 | 50 |
| B8M Class 1 | All | 75 | 30 | 30 | 50 |
| B8 Class 2 | Up to 3/4 | 125 | 100 | 12 | 35 |
| 7/8/2001 | 115 | 80 | 15 | 35 | |
| 1-1/8 - 1-1/4 | 105 | 65 | 20 | 35 | |
| 1-3/8 - 1-1/2 | 100 | 50 | 28 | 45 | |
| B8M Class 2 | Up to 3/4 | 110 | 95 | 15 | 45 |
| 7/8/2001 | 100 | 80 | 20 | 45 | |
| 1-1/8 - 1-1/4 | 95 | 65 | 25 | 45 | |
| 1-3/8 - 1-1/2 | 90 | 50 | 30 | 45 | |
| B16 | Up to 2-1/2 | 125 | 105 | 18 | 50 |
| 2-5/8 - 4 | 110 | 95 | 17 | 45 | |
| 4-1/8 - 7 | 100 | 85 | 16 | 45 |
Material Chemical Composition
| Element | B7 (AISI 4140) | B8 (AISI 304) | B8M (AISI 316) | B16 (AISI 4140) |
|---|---|---|---|---|
| Carbon | 0.37 - 0.49% | 0.08% max | 0.08% max | 0.37 - 0.49% |
| Manganese | 0.65 - 1.10% | 2.00% max | 2.00% max | 0.65 - 1.10% |
| Phosphorus, max | 0.04% | 0.05% | 0.05% | 0.04% |
| Sulfur, max | 0.04% | 0.03% | 0.03% | 0.04% |
| Silicon | 0.15 - 0.35% | 1.00% max | 1.00% max | 0.15 - 0.35% |
| Chromium | 0.75 - 1.20% | 18.0 - 20.0% | 16.0 - 18.0% | 0.75 - 1.20% |
| Nickel | 8.0 - 11.0% | 10.0 - 14.0% | ||
| Molybdenum | 0.15 - 0.25% | 2.00 - 3.00% | 0.15 - 0.25% |
Recommended Nuts, Bolts & Washers
| Bolt Grade | Nuts | Washers |
|---|---|---|
| B7 | A194 Grade 2H | F436 |
| B8 Class 1 | A194 Grade 8 | SS304 |
| B8M Class 1 | A194 Grade 8M | SS316 |
| B8 Class 2 | A194 Grade 8 | SS304 |
| B8M Class 2 | A194 Grade 8M | SS316 |
ASTM A320
ASTM A320 covers high end alloy steel bolts used in the oil and gas industry including fasteners used in valves, flanges, fittings and other components.
Grades
| L7 | AISI 4140/4142 Quenched and tempered |
|---|---|
| L43 | AISI 4340 Quenched and tempered |
| B8 Class 1 | AISI 304, carbide solution treated |
| B8 Class 2 | AISI 304, carbide solution treated, strain hardened |
| B8M Class 1 | AISI 316, carbide solution treated |
| B8M Class 2 | AISI 316, carbide solution treated, strain hardened |
Mechanical Properties
| Grade | Size | Tensile ksi, min | Yield, ksi, min | Elong, %, min | RA % min | Charpy Impact 20-ft-lbf @ temp |
|---|---|---|---|---|---|---|
| L7 | Up to 2-1/2 | 125 | 105 | 16 | 50 | -150° F |
| L43 | Up to 4 | 125 | 105 | 16 | 50 | -150° F |
| B8 Class 1 | All | 75 | 30 | 30 | 50 | N/A |
| B8 Class 2 | Up to 3/4 | 125 | 100 | 12 | 35 | N/A |
| 7/8/2001 | 115 | 80 | 15 | 35 | N/A | |
| 1-1/8 - 1-1/4 | 105 | 65 | 20 | 35 | N/A | |
| 1-3/8 - 1-1/2 | 100 | 50 | 28 | 45 | N/A | |
| B8M Class 1 | All | 75 | 30 | 30 | 50 | N/A |
| B8M Class 2 | Up to 3/4 | 110 | 95 | 15 | 45 | N/A |
| 7/8/2001 | 100 | 80 | 20 | 45 | N/A | |
| 1-1/8 - 1-1/4 | 95 | 65 | 25 | 45 | N/A | |
| 1-3/8 - 1-1/2 | 90 | 50 | 30 | 45 | N/A |
Material Chemical Composition
| Element | L7 (AISI 4140) | L43 (AISI 4340) | B8 (AISI 304) | B8M (AISI 316) |
|---|---|---|---|---|
| Carbon | 0.37 - 0.49% | 0.38 - 0.43% | 0.08% max | 0.08% max |
| Manganese | 0.65 - 1.10% | 0.75 - 1.00% | 2.00% max | 2.00% max |
| Phosphorus, max | 0.04% | 0.04% | 0.05% | 0.05% |
| Sulfur, max | 0.04% | 0.04% | 0.03% | 0.03% |
| Silicon | 0.15 - 0.35% | 0.15 - 0.35% | 1.00% max | 1.00% max |
| Chromium | 0.75 - 1.20% | 0.70 - 0.90% | 18.0 - 20.0% | 16.0 - 18.0% |
| Nickel | 1.65 - 2.00% | 8.0 - 11.0% | 10.0 - 14.0% | |
| Molybdenum | 0.15 - 0.25% | 0.02 - 0.30% | 2.00 - 3.00% |
Recommended Nuts & Washers
| Bolt Grade | Nuts | Washers |
|---|---|---|
| L7 | A194 Grade 4 or 7 | F436 |
| L43 | A194 Grade 4 or 7 | F436 |
| B8 Class 1 | A194 Grade 8 | SS304 |
| B8 Class 2 | A194 Grade 8 | SS304 |
| B8M Class 1 | A194 Grade 8M | SS316 |
| B8M Class 2 | A194 Grade 8M | SS316 |
