Manufacturer of ASTM A193 B8M Stud Bolts
ASTM A193 B8M Fasteners Specification & Properties
ASTM A193 B8M is a stainless steel grade for stud bolts, primarily used in high-temperature, high-pressure, and corrosive environments like chemical processing, marine, and offshore industries. Grase B8M Bolt is made of SS316 round bar.Which offers a superior corrosion resistance compared to B8 (304 stainless steel).
B8M Stud Bolt – Chemical Composition
| Element | Requirement (%) |
|---|---|
| Carbon (C) | ≤ 0.08 |
| Manganese (Mn) | ≤ 2.00 |
| Phosphorus (P) | ≤ 0.045 |
| Sulfur (S) | ≤ 0.030 |
| Silicon (Si) | ≤ 1.00 |
| Chromium (Cr) | 16.0 – 18.0 |
| Nickel (Ni) | 10.0 – 14.0 |
| Molybdenum (Mo) | 2.0 – 3.0 |
ASTM A193 B8M Fasteners – Mechanical Properties
| Grade | Tensile Strength (MPa / ksi) | Yield Strength (MPa / ksi) | Elongation (%) | Hardness (HRC / HBW) |
|---|---|---|---|---|
| B8M Class 1 (Solution-Annealed) | 515 MPa (75 ksi) min | 205 MPa (30 ksi) min | 30% min | ≤ 223 HBW (95 HRB max) |
| B8M Class 2 (Strain-Hardened) | 860 MPa (125 ksi) min | 620 MPa (90 ksi) min | 15% min | ≤ 321 HBW (35 HRC max) |
🔹 Class 1 → Solution-annealed
🔹 Class 2 → Strain-hardened
There are 2 different classes in ASTM A193 B8M because of different heat treatment meothid.
The class 1 products are carbide solution treated while the class 2 products are strain hardened in addition to the carbide solution treatment
ASTM A193 B8M Fasteners size and standard
ASTM A193 → Standard specification for high-temperature and high-pressure bolting.
ASME B16.5 → Stud bolt dimensions for flange bolting.
ASME B18.2.1 / B18.2.2 → Standard for bolt & nut dimensions.
ASME B1.1 / B1.13M → Unified UNC, UNF & metric thread standards.
ISO 898-1 → Metric equivalent standard for stud bolts.
Size Scope:1/2in to 2 1/2″
Length:customize length upto 3000mm length
Recommended Nuts, & Washer for B8M Fasteners
What is the difference between A193 Grade B8 and Grade B8M?
These bolts are both stainless bolt grade with similar strength requirements but differ in their corrosion resistance. Grade B8 bolts are made from type 304 stainless steel, while Grade B8M bolts are made from a more corrosion-resistant type 316 stainless steel.
ASTM A193 B8M Bolt – Applications
✔ Offshore & Marine Environments (Corrosion resistance in seawater)
✔ Chemical & Petrochemical Plants (Acidic & aggressive chemicals)
✔ Power Plants & Boilers (High-temperature performance)
✔ Food & Pharmaceutical Industry (Hygienic, corrosion-resistant)
