JIS G3463 — Stainless steel pipes for boilers and heat exchangers
Grades
SUS304TB, SUS304HTB, SUS309STB, SUS309HTB, SUS310STB, SUS310HTB, SUS316TB, SUS316HTB, SUS321TB, SUS321HTB, SUS347TB, SUS347HTB
Chemical composition and mechanical properties
| Grade | Chemical composition | Mechanical properties |
|---|---|---|
| SUS304TB | C≤0.08, Si≤1.00, Mn≤2.00, P≤0.045, S≤0.030, Cr 18.00-20.00, Ni 8.00-11.00 | Rm ≥520 MPa, Rp0.2 ≥205 MPa, A≥35%, HB≤187 |
| SUS304HTB | C 0.04-0.10, Si≤1.00, Mn≤2.00, P≤0.045, S≤0.030, Cr 18.00-20.00, Ni 8.00-11.00 | Rm ≥520 MPa, Rp0.2 ≥205 MPa, A≥35%, HB≤187 |
| SUS309STB | C≤0.08, Si≤1.00, Mn≤2.00, P≤0.045, S≤0.030, Cr 22.00-24.00, Ni 12.00-15.00 | Rm ≥520 MPa, Rp0.2 ≥205 MPa, A≥35% |
Application scope
JIS G3463 specifies seamless stainless steel tubes for boilers, heat exchangers, and condensers, typically delivered in a solution-annealed state. The grades are primarily austenitic, including high-carbon, stabilized, and high-chromium-nickel heat-resistant varieties, possessing good high-temperature strength, oxidation resistance, and corrosion resistance. The standard specifies high-temperature mechanical properties and corrosion resistance tests, and is suitable for small-diameter pressure-bearing pipe fittings in heat-receiving surfaces and heat transfer areas.
Typical applications
Mainly used in boiler superheaters, reheaters, and economizer tubes, as well as heat transfer tube bundles in various heat exchangers and condensers. Also used in high-temperature heat exchange equipment piping in the chemical and power industries. Stabilized and high-carbon varieties are suitable for resistance to intergranular corrosion and high-temperature durability requirements, while high-chromium-nickel varieties have better oxidation resistance and heat resistance, and are often used in heat exchange surfaces and heat exchange conditions with high wall temperatures and corrosive media.
