ASTM A193 Grade B8MA Bolts, Stud Bolts, Fasteners
Standard Specification for Alloy-Steel and Stainless Steel Bolting for High Temperature or High Pressure Service and Other Special Purpose Applications
ASTM A193 specification covers alloy and stainless steel bolting for pressure vessels, valves, flanges, and fittings for high temperature or high pressure service, or other special purpose applications. Several grades are covered, including ferritic steels and austenitic stainless steels designated B5, B6, B7, B8, B8M, etc.
Selection will depend upon design, service conditions, mechanical properties, and high temperature characteristics. This specification is expressed in both inch-pound units
and in SI units; however, unless the purchase order or contract specifies the applicable A193M specification designation (SI units), the inch-pound units shall apply
ASTM A193 Grade B8MA Raw Material
| Grade |
Raw Material Description |
| B8MA |
AISI 316 Stainless Steel, Carbide Solution Treated in Finished Condition |
ASTM A193 Grade B8MA Properties
ASTM A193 Grade B8MA Chemical Composition |
| Carbon, max |
Manganese, max |
Phosphorus, max |
Sulfur, max |
Silicon, max |
Chromium |
Molybdenum |
| 0.08 |
2.00 |
0.045 |
0.030 |
1.00 |
16.0 - 18.0 |
2.00 - 3.00 |
ASTM A193 Grade B8MA Mechanical Properties |
| Grade |
Diameter |
Tensile Strength |
Yield Strength |
Elongation |
Reduction |
Hardness |
| Grade B8MA |
All Diameters |
515 |
205 |
30 |
50 |
192 HBW or 90 HRB |
ASTM A193 Grade B8MA Bolt Marking
| Class |
Manufacturer's Mark |
Grade Symbol |
| Class 1A |
BPF |
B8D or B8MA |
Recommended Nuts & Washers
| Bolting Grade |
Nut Grade |
Washer Grade |
| ASTM A193 Grade B8MA |
ASTM A194 Grade 8MA |
SS 316 |
ASTM A193 Grade B8MA Bolting