ASTM A193 Standard Specification for Alloy-Steel and Stainless Steel Bolting for High Temperature or High Pressure Service and Other Special Purpose Applications
This specification covers alloy and stainless steel bolting materials and bolting components for pressure vessels, valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications. See Specification A962/A962M for the definition of bolting. Bars and wire shall be hot-wrought and may be further processed by centerless grinding or by cold drawing. Austenitic stainless steel may be carbide solution treated or carbide solution treated and strain-hardened. When strain hardened austenitic stainless steel is ordered, the purchaser should take special care to ensure that Appendix X1 is thoroughly understood
Download A 193 A193M Standard
A193 Grades
Alloy steel, AISI 4140 / 4142 quenched and tempered.
A193 Grade B8, Class 1:
Stainless steel, AISI 304, carbide solution treated.
A193 Grade B8, Class 2:
Stainless steel, AISI 304, carbide solution treated, strain hardened.
A193 Grade B8M, Class 1:
Stainless steel, AISI 316, carbide solution treated.
A193 Grade B8M, Class 2:
Stainless steel, AISI 316, carbide solution treated, strain hardened.
Alloy steel, chromium-molybdenum-vanadium, quenched and tempered.
NOTE: There are other grades of A193. Those listed here are the ones we receive the most requests for. For information on other types, please contact us
A193 MECHANICAL PROPERTIES |
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|---|---|---|---|---|---|---|---|
| Grade | Size | Tensile, ksi, min | Yield, ksi, min | Elong. % min | RA min | HBW, max | HRC, max |
| B7 | up to 2-1/2″ | 125 | 105 | 16 | 50 | 321 | 35 |
| 2-5/8″ – 4″ | 115 | 95 | 16 | 50 | |||
| 4-1/8″ – 7″ | 100 | 75 | 18 | 50 | |||
| B8 Class 1 | all | 75 | 30 | 30 | 50 | 223 | 35 |
| B8 Class 2 | up to 3/4″ | 125 | 100 | 12 | 35 | 321 | 35 |
| 7/8″ – 1″ | 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 1 | all | 75 | 30 | 30 | 50 | 223 | 96 |
| B8M Class 2 | up to 3/4″ | 110 | 95 | 15 | 45 | 321 | 35 |
| 7/8″ – 1″ | 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 | under 2-1/2″ | 125 | 105 | 18 | 50 | 321 | 35 |
| over 2-1/2″ – 4″ | 110 | 95 | 17 | 45 | |||
| over 4″ – 8″ | 100 | 85 | 16 | 45 | |||
A193 CHEMICAL PROPERTIES |
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|---|---|---|---|---|
| Element | Grade B7 | Grade B8 | Grade B8M | Grade B16 |
| Carbon | 0.37 – 0.49% | 0.08% max | 0.08% max | 0.36 – 0.47% |
| Manganese | 0.65 – 1.1% | 2.0% max | 2.0% max | 0.45 – 0.7% |
| Phosphorus, max | 0.035% | 0.045% | 0.045% | 0.035% |
| Sulfur, max | 0.04% | 0.03% | 0.03% | 0.04% |
| Silicon | 0.15 – 0.35% | 1.0% max | 1.0% max | 0.15 – 0.35% |
| Chromium | 0.75 – 1.2% | 18.0 – 20.0% | 16.0 – 18.0% | 0.8 – 1.15% |
| Nickel | 8.0 – 11.0% | 10.0 – 14.0% | ||
| Molybdenum | 0.15 – 0.25% | 2.0 – 3.0% | 0.5 – 0.65% | |
| Vanadium | 0.25 – 0.35% | |||
| Aluminum, max* | 0.015% | |||
A193 RECOMMENDED NUTS/WASHER |
||
|---|---|---|
| Grade | Nut | Washer |
| B7 | A194 Grade 2H | F436 |
| B8 Class 1 | A194 Grade 8 | 304 Stainless |
| B8 Class 2 | A194 Grade 8 | 304 Stainless |
| B8M Class 1 | A194 Grade 8M | 316 Stainless |
| B8M Class 2 | A194 Grade 8M | 316 Stainless |
| B16 | A194 Grade 7 | F436 |
