ASTM A403 — Wrought austenitic stainless steel piping fittings
ASTM A403 covers wrought austenitic stainless steel fittings for pressure piping — elbows, tees, reducers, caps, stub ends — in seamless and welded construction. Class WP fittings are made to ASME B16.9/B16.28 and tested to the related pipe specification; class CR fittings are made to MSS SP-43 for light-wall service. Suffixes S, W and WX identify seamless, welded and welded with full radiography.
ASTM A403 at a glance
| Standard | ASTM A403 |
|---|---|
| Issued by | ASTM / ASME (SA-403) |
| Product form | Butt-weld fittings |
| Typical use | Stainless steel butt-weld fittings |
| Grades on this site | 10 |
Equivalent and related standards
ASTM A403 grades — chemistry and mechanical properties
| Grade | UNS | C% | Cr% | Ni% | Mo% | YieldMPa min | TensileMPa min |
|---|---|---|---|---|---|---|---|
| ASTM A403 WP304 | S30400 | 0.08 max | 18.0–20.0 | 8.0–11.0 | — | 205 | 515 |
| ASTM A403 WP304L | S30403 | 0.030 max | 18.0–20.0 | 8.0–12.0 | — | 170 | 485 |
| ASTM A403 WP316 | S31600 | 0.08 max | 16.0–18.0 | 10.0–14.0 | 2.00–3.00 | 205 | 515 |
| ASTM A403 WP316L | S31603 | 0.030 max | 16.0–18.0 | 10.0–14.0 | 2.00–3.00 | 170 | 485 |
| UNS N08904 (904L) | N08904 | 0.020 max | 19.0–23.0 | 23.0–28.0 | 4.0–5.0 | 215 | 490 |
| ASTM A403 WP321 | S32100 | 0.08 max | 17.0–19.0 | 9.0–12.0 | — | 205 | 515 |
| ASTM A403 WP347 | S34700 | 0.08 max | 17.0–19.0 | 9.0–13.0 | — | 205 | 515 |
| ASTM A403 WP310S | S31008 | 0.08 max | 24.0–26.0 | 19.0–22.0 | 0.75 max | 205 | 515 |
| ASTM A403 WP317L | S31703 | 0.030 max | 18.0–20.0 | 11.0–15.0 | 3.0–4.0 | 205 | 515 |
| ASTM A182 F44 (254 SMO) | S31254 | 0.020 max | 19.5–20.5 | 17.5–18.5 | 6.0–6.5 | 300 | 650 |
Reference information compiled from the published standard for convenience. It does not replace the current edition of the governing standard, which takes precedence. Verify critical dimensions and properties before design, purchase or fabrication. Teshi Engineers & Sales Promoters (P) Ltd accepts no liability for errors or omissions.
FAQ
ASTM A403: common questions
Which grades does ASTM A403 cover?
On this site: ASTM A403 WP304, ASTM A403 WP304L, ASTM A403 WP316, ASTM A403 WP316L, UNS N08904 (904L), ASTM A403 WP321, ASTM A403 WP347, ASTM A403 WP310S, ASTM A403 WP317L, ASTM A182 F44 (254 SMO). Open any grade for its full chemical composition, mechanical properties and PDF data sheet.
Does Teshi Group supply material to ASTM A403?
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.
Other butt-weld fittings standards
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