Overview of ASME SA193M Gr.B7 Bolts

2026-09-21 08:18:50

ASME SA193M Gr.B7 bolt is a high-strength fastener manufactured from chromium-molybdenum alloy steel (primarily 4140 and 4142 alloy steels). This grade is specified under the standard established by the American Society of Mechanical Engineers (ASME), intended primarily for high-temperature and high-pressure service. Thanks to its favorable mechanical properties and corrosion resistance, Gr.B7 bolts serve as indispensable critical components in petrochemical, energy, construction and other industries.

Properties of ASME SA193M Gr.B7 Bolts

• High strength: Gr.B7 bolts feature a minimum tensile strength of 860 MPa and a minimum yield strength of 725 MPa, ensuring resistance to fracture under heavy loads.

• Heat resistance: It maintains excellent mechanical properties at temperatures up to 450°C, suitable for high-temperature operating conditions.

• Corrosion resistance: The presence of chromium improves the alloy’s corrosion resistance, allowing Gr.B7 bolts to be used in corrosive media for extended service life.

• Toughness and ductility: It possesses good toughness and ductility, capable of absorbing energy without brittle failure, and suited for applications subjected to dynamic or impact loads.

Wide Application of ASME SA193M Gr.B7 Bolts in Various Industrial Sectors

• Petrochemical industry: Used as critical fasteners for reactors, heat exchangers and flange joints under high temperature and high pressure.

• Power plants: Applied to connections of boilers, auxiliary equipment and pressure vessels to guarantee stable operation of large-scale facilities.

• Construction: Deployed at strength-critical locations in bridges, high-rise buildings and other structures.

• Aerospace: Utilized in components requiring high strength and long-term durability to ensure flight safety.