JIS G3203 — Alloy steel forgings for pressure vessels for high-temperature service
JIS G3203 covers Cr-Mo alloy steel forgings for high-temperature pressure vessels, designated SFVA (SFVAF1, SFVAF11A, SFVAF22B, SFVAF5, SFVAF9, SFVAF28) — the Japanese counterpart of ASTM A182 Cr-Mo grades.
JIS G3203 at a glance
| Standard | JIS G3203 |
|---|---|
| Issued by | Japanese Industrial Standards |
| Product form | Forgings |
| Grades on this site | 9 |
JIS G3203 grades and their ASTM equivalents
| JIS designation | Nearest ASTM / ASME grades | UNS | W.Nr |
|---|---|---|---|
| STPA12 / SFVAF1 | ASTM A182 F1, ASTM A335 P1, ASTM A234 WP1 | K12822 | 1.5415 |
| STPA20 / SFVAF2 | ASTM A182 F2, ASTM A335 P2 | K12122 | — |
| STPA22 / SFVAF12 | ASTM A182 F12 Cl.2, ASTM A335 P12, ASTM A182 F12 Cl.1, ASTM A234 WP12 Cl.1 | K11564 | 1.7335 |
| STPA23 / SFVAF11A | ASTM A182 F11 Cl.2, ASTM A234 WP11 Cl.1, ASTM A335 P11, ASTM A182 F11 Cl.1, ASTM A182 F11 Cl.3, ASTM A234 WP11 Cl.2 | K11572 | 1.7335 |
| STPA24 / SFVAF22B | ASTM A182 F22 Cl.3, ASTM A234 WP22 Cl.1, ASTM A335 P22, ASTM A182 F22 Cl.1, ASTM A234 WP22 Cl.3 | K21590 | 1.7380 |
| SFVAF21A | ASTM A182 F21, ASTM A335 P21 | K31545 | — |
| STPA25 / SFVAF5B | ASTM A182 F5, ASTM A234 WP5 Cl.1, ASTM A335 P5, ASTM A182 F5a | K41545 | 1.7362 |
| STPA26 / SFVAF9 | ASTM A182 F9, ASTM A234 WP9 Cl.1, ASTM A335 P9 | K90941 | 1.7386 |
| STPA28 (JIS G3458) / SFVAF28 (JIS G3203) | ASTM A182 F91, ASTM A335 P91, ASTM A234 WP91 Type 1 | K90901 | 1.4903 |
Equivalents are the nearest commonly cited grades. Chemistry, mechanical properties and testing differ between standards — compare them before substituting one for another.
FAQ
JIS G3203: common questions
What is the ASTM equivalent of JIS G3203 STPA12 / SFVAF1?
The nearest ASTM grades are ASTM A182 F1, ASTM A335 P1, ASTM A234 WP1.
Does Teshi Group supply material to JIS G3203?
Teshi Group manufactures flanges, fittings, fasteners and valves, and supplies pipes and plates, to ASTM / ASME specifications and to equivalent EN, JIS, GB and IS standards on request, with EN 10204 3.1 certificates. Send your requirement to info@teshigroup.com.
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