ASTM A789 UNS S82441 Lean Duplex Stainless Steel Tube

ASTM A789 / A789M covers seamless and welded ferritic/austenitic stainless steel tubing for general corrosion service with particular emphasis on stress corrosion cracking resistance. UNS S82441 — often associated with LDX 2404-type lean duplex — has heat limits of carbon ≤0.030%, chromium 23.0–25.0%, nickel 3.0–4.5%, manganese 2.50–4.00%, molybdenum 1.00–2.00%, nitrogen 0.20–0.30%, copper 0.10–0.80%, and sulfur ≤0.005% in A789/A789M-24 Table 1. Mo 1–2% with high N makes it one of the stronger lean options toward the 2205 border.

SHH STEEL can produce and supply ASTM A789 UNS S82441 lean duplex stainless steel tube as seamless and welded product (welded without filler metal) in typical OD × wall / BWG sizes, with EN 10204 3.1 mill test certificates. Dual A789/SA789 marking only when both standards are on the order. Hub: A789/A789M.

Compare with A789 S32003, A789 S32101, and A789 S32205. Plate: A240.

Heat analysis must meet A789/A789M-24 Table 1. Product analysis follows A480/A480M annex tolerances when ordered.

Mid-range PREN = Cr + 3.3Mo + 16N at Cr 24, Mo 1.5, N 0.25 is about PREN ≈ 33 — high for lean, approaching standard duplex screening. Wall-split mechanical floors apply in older Table 4 copies.

Tensile and hardness floors come from older A789 Table 4 reprints; the public A789/A789M-24 sample did not include that table. Reconfirm on the PO edition.

Thin wall 107/78 ksi; thicker 99/70 ksi; elong 25%; hardness max 290 HBW / 30 HRC.

A789 Section 5 allows seamless or welded manufacture with no filler metal added. Seamless S82441 tube is typically hot-finished then cold-drawn to final OD and wall; welded tube is roll-formed from matching strip and autogenously welded, then usually cold-worked and re-annealed so the seam meets parent-metal heat treatment and mechanical floors.

Seamless lots take a flaring test (minimum 10% inside-diameter expansion); welded lots take a flange test plus a reverse flattening test on a specimen from each 1500 ft [450 m] of finished tubing. Tension and hardness sampling apply to both routes. SHH STEEL produces and supplies both seamless and welded A789 S82441 against the route named on the enquiry, with EN 10204 3.1 coverage of chemistry and mechanicals.

Average wall is the default under A789; specify minimum wall on the order when that is the design basis. Outside diameter and wall are ordered as tube sizes (metric or inch OD × wall / BWG). General dimensional requirements sit in Specification A1016/A1016M unless A789 states otherwise.

When converting a pipe schedule into tube wall, state clearly whether acceptance is average or minimum wall — the two are not interchangeable on the mill ticket. SHH STEEL confirms OD × wall, length, and finish before the heat is reserved.

Often linked to LDX 2404-type trade naming; certify to UNS S82441.

Hub: A789/A789M.

A789/A789M-24 Table 2 lists UNS S82441 at 1830 °F [1000 °C] min. Follow the quench stated in Table 2. Seamless tube may be quenched directly after hot forming while at or above the minimum solution temperature where that alternate is allowed.

Rapid cooling limits time in the sigma-forming window (roughly 700–1000 °C). A789’s scope warns that these steels are susceptible to embrittlement if used for prolonged periods at elevated temperatures, including 475 °C (885 °F) ferrite embrittlement. SHH STEEL supplies S82441 in the heat-treated condition required by Table 2.

S82441 sits near the top of the lean band (mid-range PREN ≈33) with purposeful Mo 1–2%. Better crevice screening than Mo-max lean grades; still usually below a full A789 S32205 Mo 3–3.5% design. Not a seawater A789 S32750 substitute.

Process water, light chloride exchangers, and structural/pressure tube where LDX 2404 / S82441 is frozen. Account for wall-split mechanical floors. SHH STEEL produces and supplies A789 S82441 for enquiry sizes.

Autogenous A789 welded tube must meet parent anneal and mechanicals without filler. Fabrication welds that use filler typically take matching or overalloyed duplex/super duplex consumables with controlled heat input and interpass temperature so ferrite–austenite balance stays qualified. Re-anneal after heavy hot work when required; keep bake and stress-relief cycles out of the sigma nose and the 400–500 °C embrittlement band unless a qualified procedure says otherwise.

Standard delivery is solution-annealed and pickled (or otherwise descaled) so the passive film can form uniformly. Bright-annealed or lightly polished OD/ID finishes are available by agreement when the exchanger or hygienic duty needs a smoother bore. Passivation after pickling or after fabrication welding is good practice in chloride service; remove carbon-steel tooling contamination before commissioning. SHH STEEL states the finish route on the quotation and on the MTC.

Each A789 tube takes either a nondestructive electric test or a hydrostatic test. Mechanical sampling covers tension, hardness, and flaring for seamless or flange plus reverse flattening for welded, with full heat analysis on the mill test certificate. Product analysis and supplementary corrosion or ferrite tests are added when the purchase order asks for them. SHH STEEL issues EN 10204 3.1 as standard and arranges third-party inspection / 3.2 when the enquiry names an agency, with lot identity per A789 Notes 1 and 2.

Tube is typically packed in hexagonal bundles or plywood cases with end protectors and waterproof wrapping for ocean freight, with bundle tags repeating heat number, size, and standard. Cut-to-length exchanger tube may be boxed by length group; U-bends travel in purpose-built crates when ordered. SHH STEEL ships FOB, CFR, CIF, or EXW under the Incoterm on the order, with commercial invoice, packing list, and the EN 10204 3.1 or 3.2 certificate set.

SHH STEEL produces and supplies ASTM A789 UNS S82441 — coordinating Mo-bearing lean chemistry, the 1830 °F min anneal, testing, and EN 10204 3.1 documents to the PO. Production capability, not trader-only.

SHH STEEL can produce and supply ASTM A789 UNS S82441 against the edition, size, and finish route named on your enquiry. The capability table below summarizes what we regularly quote, followed by the Stock / Available sizes map.

Stock / Available sizes

SHH STEEL quotes S82441 tube against a practical production-and-stock enquiry range rather than a frozen warehouse SKU list with published tonnages. Availability of any single line on a given week depends on mill drawing and inbound schedule — treat the table as a supply map for enquiry.

When you send an enquiry, include the ASTM edition if known, seamless or welded, OD × wall (avg or min), length, finish, test extras, and destination port. Sister grades such as A789 S32003, A789 S32101, and A789 S32205 can be quoted on the same enquiry when the project mixes duplex classes.

ASTM A789 UNS S82441 is covered here as lean duplex stainless steel tube under the A789 seamless-and-welded duplex tubing specification. SHH STEEL produces and supplies seamless and welded S82441 to the A789 heat-treatment and test regime with EN 10204 3.1 documentation. For sizes, dual marking, or grade comparisons, contact admin@steelspecs.com.