ASTM A193 Grade B7m and Grade B7 are chromium-molybdenum alloy steel bolting material specifications intended for high-temperature and high-pressure service. While they share the same base chemical composition, they undergo different heat treatments to serve distinct industrial environments. For full industry standard compliance, refer to official ASTM International Standards.
Grade B7 is the industry standard for high-temperature applications, offering high tensile strength up to 125 ksi. ASTM A193 Grade B7m, however, is tempered at a higher temperature to yield a lower hardness (maximum 235 HBW) and lower tensile strength. This specific processing makes ASTM A193 Grade B7m bolts highly resistant to stress corrosion cracking (SCC) and hydrogen embrittlement, making them essential for sour gas (H₂S) conditions.
Ananka Group is a trusted manufacturer of both fastener grades. Whether you require standard B7 bolts or ASTM A193 Grade B7m fasteners paired with ASTM A194 Grade 2HM Nuts for pressure vessels, flanges, and aggressive petrochemical or offshore applications, our products deliver ultimate safety and reliability.