ASTM A790 / ASME SA-790 / UNS S32205 / W.Nr. 1.4462
Thaida Stainless Steel Manufacturing (Thailand) Co., Ltd. supplies ASTM A790 duplex steel UNS S32205 seamless pipes from its Ban Bueng, Chonburi, Thailand factory, offering the tighter, higher-nitrogen version of the 22Cr duplex chemistry for new seawater, offshore, desalination and sour-service piping. Designated EN 1.4462 in European standards, the grade sits within our duplex steel seamless pipes range. Quotations, drawings and order follow-up are handled by our office in Bang Phli, Samut Prakan.
Duplex Steel UNS S32205 seamless pipeUNS S32205 / W.Nr. 1.4462
EN 10204 3.1 certificate / 3.2 on request
Order by NPS and schedule or by outside diameter and wall thickness; both routes are open within the production limits below. Cut lengths are held to your figure, with no pipe shorter than ordered and none more than 6 mm over it.
We make every ASTM A790 UNS S32205 seamless pipe to the chemistry, heat treatment, mechanical test and pressure or electric test requirements of ASTM A790 / ASME SA-790, a specification aimed at general corrosive service and, above all, at resistance to stress corrosion cracking. At our option the pipe is hot finished or cold finished, then pickled free of scale or bright annealed. For heat exchanger and instrument service sized by OD and wall, the same grade is produced to ASTM A789 as UNS S32205 seamless tubes.
Each length is either pressure tested hydrostatically or examined by ultrasonic or eddy current testing after final heat treatment and straightening. Hydrostatic pressure is calculated with a stress of 50% of the 450 MPa minimum yield and held for at least 5 seconds. From each lot we also take one tension test (two for lots over 100 pipes), flatten 5% of the pipes and hardness test two pipes. Results go on an EN 10204 3.1 (3.2 on request) material test certificate, supported by 100% PMI and heat treatment charts, and third-party inspection is available on request.
ASTM A790 / ASME SA-790 limits; single values are maximums:
UNS S32205S32205
| Element | UNS S32205 (%) |
|---|---|
| C (Carbon) | 0.030 |
| Mn (Manganese) | 2.00 |
| P (Phosphorus) | 0.030 |
| S (Sulfur) | 0.020 |
| Si (Silicon) | 1.00 |
| Ni (Nickel) | 4.5 to 6.5 |
| Cr (Chromium) | 22.0 to 23.0 |
| Mo (Molybdenum) | 3.0 to 3.5 |
| N (Nitrogen) | 0.14 to 0.20 |
Nickel and the residual elements carry the same limits as UNS S31803 seamless pipes; the difference lies in the minimums. S32205 starts at 22.0% chromium instead of 21.0%, 3.0% molybdenum instead of 2.5% and 0.14% nitrogen instead of 0.08%, so no heat can sit at the lean end of the 22Cr range, and corrosion resistance stays more uniform from heat to heat.
| Property | Requirement per ASTM A790 |
|---|---|
| Tensile Strength, min | 655 MPa (95 ksi) |
| Yield Strength, min | 450 MPa (65 ksi) |
| Elongation in 2 in. or 50 mm, min | 25% |
| Hardness, max | 290 HBW or 30 HRC |
Under A790, the S32205 tensile minimum is 655 MPa against 620 MPa for S31803, while the yield minimum is 450 MPa for both grades. Elongation and hardness limits are identical for the two grades, and the actual results for your heat are reported against them.
Cross-references for UNS S32205 in US, EN, JIS and GB standards, given for the ASTM A790 grade:
For new seawater and process headers in mid and large bores, the table gives ASTM A790 wall thickness in mm for NPS 4 to 12, together with the permitted outside diameter variation that applies to A790 pipe in each size band.
| NPS | DN | OD (mm) | OD Tolerance (mm) | Sch 5S | Sch 10S | Sch 40S | Sch 80S |
|---|---|---|---|---|---|---|---|
| 4 | 100 | 114.30 | +0.8 / -0.8 | 2.11 | 3.05 | 6.02 | 8.56 |
| 5 | 125 | 141.30 | +1.6 / -0.8 | 2.77 | 3.40 | 6.55 | 9.52 |
| 6 | 150 | 168.28 | +1.6 / -0.8 | 2.77 | 3.40 | 7.11 | 10.97 |
| 8 | 200 | 219.08 | +1.6 / -0.8 | 2.77 | 3.76 | 8.18 | 12.70 |
| 10 | 250 | 273.05 | +2.4 / -0.8 | 3.40 | 4.19 | 9.27 | 12.70 |
| 12 | 300 | 323.85 | +2.4 / -0.8 | 3.96 | 4.57 | 9.52 | 12.70 |
Swipe sideways to see the full table.
On these sizes, nominal wall may run 22.5% over or 12.5% under when the wall is 5% of the OD or less, and 15.0% over or 12.5% under on heavier walls. On thin-wall pipe, with the wall at 3% of the OD or less, as on NPS 12 Schedule 10S, the OD tolerance applies to the mean of the extreme readings and ovality is limited to 1.5% of the specified OD. Outside the table, we produce seamless 1.4462 duplex pipe to the OD and wall on your drawing.
New-build systems carrying seawater, brine, chlorides or sour hydrocarbons are where the higher S32205 minimums pay off.
Seawater intake headers and coastal power plant cooling loops use the grade where chloride pitting and crevice attack shorten austenitic lines, and duplex strength keeps large-bore walls and weights moderate.
High-pressure seawater feed and concentrated brine lines in desalination plants run on seamless S32205 duplex steel pipe, which combines chloride resistance with a lighter wall than an austenitic design.
Produced-water, process and oil field lines on offshore platforms and onshore wells handle chlorides together with hydrogen sulfide, and seamless lengths leave no longitudinal seam in these pressure lines.
Chemical process equipment and transfer lines in acid production carry mixed chloride streams, and the grade takes over from austenitic stainless steel where stress corrosion cracking has ended its service life.
Flue gas desulfurization scrubbers circulate acidic, chloride-rich slurry, and recirculation and absorber feed lines in S32205 resist the pitting and crevice corrosion that this duty produces.
Digester circulation and bleach washer lines in pulp mills combine hot alkaline liquor with chloride-bearing bleach filtrate, a combined duty that one S32205 line class can cover.
Packing
Steel-strapped bundles or wooden cases, chosen by bore size and export route.
Marking
Grade, ASTM A790, size, schedule and heat number stenciled on each length; customer tags on request.
Bore and bevel protection
Plastic end caps on both ends of every length.
Paperwork
Material test certificate and packing list travel with each consignment.
Trade terms
FOB, CIF or CFR from Thailand.
Destinations
Project sites throughout Thailand, and export shipments to Singapore, Malaysia, Vietnam, Indonesia, the Philippines and India.
UNS S32205 seamless pipe to ASTM A790 currently trades at roughly USD 5 to 11 per kg on market quotations, and that band is a guide only. Your price is set by NPS, schedule, length, quantity and any testing you add, with small lots and heavy walls toward the top of the band. Send Thaida your size list for a firm figure.
Indicative only. Send your sizes and specification to Thaida for a firm quotation.
Our factory at 154 Moo.1 Map Phai, Ban Bueng, Chonburi 20170, Thailand, pierces, finishes, heat treats and tests each duplex steel UNS S32205 seamless pipe before dispatch. Commercial questions, drawings and documents go to our office at 89/18 Moo.15 Enterprize Park, Bangna-Trad Road, Bang Kaeo, Bang Phli, Samut Prakan 10540, Thailand. Where chloride levels go beyond 22Cr duplex, our super duplex steel seamless pipes are the next step up.
Because S32205 fixes the upper part of the 22Cr duplex chemistry and a higher tensile minimum, while still meeting every S31803 composition and tensile limit. A new line class written around S32205 accepts no lean heats, and pipe certified to both UNS numbers is available on request where an existing specification names S31803.
Yes, within limits. UNS S32205 is approved for sour service under NACE MR0175 / ISO 15156, but the hardness and environmental limits of that standard still apply. ASTM A790 itself caps hardness at 290 HBW or 30 HRC; give the sour-service environment on the order so the MR0175 / ISO 15156 limits can be checked against it before production.
Your design code turns the 655 MPa tensile and 450 MPa yield minimums into an allowable stress, which with the design pressure fixes the required wall. Since nominal wall may run 12.5% under, the schedule must cover that margin. Alternatively, order on a minimum-wall basis, which permits no under-tolerance, and we quote the resulting wall.
Up to 720 mm OD. ASTM A790 lists Schedule 40S and 80S walls up to NPS 12, with the thinner 5S and 10S walls continuing into larger bores, and other dimensions are allowed when the pipe meets all other requirements of the standard. We produce walls up to 65 mm and lengths up to 18 m.
Solution treated and free of scale. ASTM A790 calls for heat treatment at 1020 to 1100 °C with rapid cooling, or for individual quenching straight after hot forming while the pipe is still at or above that minimum temperature. If you need a bright-annealed surface instead of a pickled one, state it on the order.
Only in Schedule 40S and 80S. ASTM A790 notes that Schedule 5S and 10S walls do not permit threading to ANSI B1.20.1, so thin-wall lengths are supplied plain end or beveled for butt welding. Threaded ends on the heavier schedules are cut on request.
Not automatically. WNR 1.4462 covers both UNS S31803 and UNS S32205, so a drawing that calls for seamless 1.4462 duplex pipe does not by itself fix the tighter S32205 chemistry. Put UNS S32205 and ASTM A790 on the order, and the pipe is made and tested to those limits.
Four supplementary requirements of ASTM A790: product analysis (S1), transverse tension on pipe over NPS 8 (S2), flattening on each pipe (S3) and etching (S4). Name them on the order, and add third-party witnessing if your inspection plan calls for it.
Request a Quote for Duplex Steel UNS S32205 Seamless Pipes
or email sales@thaida.co.th
