GB/T 713.7 - 2023 Steel Plates and Strips for Pressure Equipment—Part 7: Stainless and Heat-Resisting Steels
GB/T 713.7-2023 "Steel Plates and Strips for Pressure Equipment—Part 7: Stainless and Heat-Resisting Steels" is a Chinese national recommended standard released and implemented in 2023. It forms a key part of the GB/T 713 series "Steel Plates and Strips for Pressure Equipment." This standard specifically addresses stainless and heat-resisting steel plates and strips used in pressure equipment such as boilers, pressure vessels, and pressure piping, specifying requirements for dimensions, tolerances, technical specifications, test methods, inspection rules, and packaging markings.
The standard covers various typical grades, including austenitic steels (e.g., S30408, S31608), austenitic-ferritic (duplex steels, e.g., S22053, S21953), ferritic steels, and certain heat-resisting steels. It establishes clear requirements for chemical composition, mechanical properties (such as tensile strength, yield strength, and elongation after fracture), technological performance (including bending tests and intergranular corrosion tests), and ultrasonic testing to ensure the material's safety and reliability under severe service conditions involving high temperature, high pressure, and corrosion.
Compared to previous versions, GB/T 713.7-2023 further refines the grade system, updates technical specifications, and aligns with international advanced standards, enhancing its applicability and technological advancement. Its implementation provides an authoritative basis for material selection, manufacturing, and inspection of pressure equipment, playing a significant role in ensuring the safe operation of special equipment, improving domestic stainless steel product quality, and promoting industry-wide technological progress.
