ASTM A193 Grade B8C 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 B8C Raw Material

Grade Tensile Class Raw Material Description
B8C Class 1 AISI 347 Stainless Steel, Carbide Solution Treated
B8C Class 2 AISI 347 Stainless Steel, Carbide Solution Treated and Strained Hardened

ASTM A193 Grade B8C Properties

ASTM A193 Grade B8C Chemical Composition

Carbon, max Manganese, max Phosphorus, max Sulfur, max Silicon, max Chromium Molybdenum Columnium + Tantalum
0.08 2.00 0.045 0.030 1.00 17.0-19.0 - 10 x carbon content, min – 1.10 max

ASTM A193 Grade B8C Mechanical Properties

Grade Diameter Tensile Strength Yield Strength Elongation Reduction Hardness
Grade B8C M20 and under 860 690 12 35 321 HBW or 35 HRC
Grade B8C M20 to M24, inclusive 690 550 20 45 321 HBW or 35 HRC
Grade B8C M24 to M30, inclusive 655 450 25 45 321 HBW or 35 HRC
Grade B8C M30 to M36, inclusive 620 345 30 45 321 HBW or 35 HRC

ASTM A193 Grade B8C Bolt Marking

Class Manufacturer's Mark Grade Symbol
Class 1 BPF B8C
Class 2 BPF B8CSH

Recommended Nuts & Washers

Bolting Grade Nut Grade Washer Grade
ASTM A193 Grade B8C ASTM A194 Grade 8C SS 347

ASTM A193 Grade B8C Bolting

Hex Bolt Heavy Hex Bolts Stud Bolts Threaded Rods Anchor Bolts
Eye Bolts Socket Head Cap Screws Countersunk Screws J Bolts Square Head Bolts