ASME SA789 UNS S82441 Lean Duplex Stainless Steel Tube
What is ASME SA789 UNS S82441 Lean Duplex Stainless Steel Tube
ASME SA-789 / SA-789M lists UNS S82441 as a lean duplex with chromium 23.0–25.0%, nickel 3.0–4.5%, molybdenum 1.00–2.00%, nitrogen 0.20–0.30%, manganese 2.50–4.00%, copper 0.10–0.80%, carbon ≤0.030%. Higher Cr/Mo/N than the leanest rows push estimated PREN toward the top of the lean band while nickel stays moderate.
SHH STEEL can produce and supply ASME SA789 UNS S82441 lean duplex stainless steel tube in seamless and welded (no filler metal) forms, with EN 10204 3.1 MTCs reporting Mn/Cu and wall-dependent tensile floors, plus Table 2 heat treatment at 1830 °F [1000 °C] minimum. Dual marking is available when requested.
Compare SA789 S82011, SA789 S82031, SA789 S32101, SA789 S32304; step to SA789 S32205 for standard duplex. Plate: A240 / SA240. Hub: SA789/SA789M. Keep the ASME designation on Code purchase orders even when dual ASTM marking is also requested for documentation convenience.
Chemical Composition of SA789 S82441
Table 1 of ASME SA-789 fixes the heat analysis for S82441. Product analysis applies when Section 8 or the purchase order invokes it through A1016/A1016M, using A480/A480M tolerances. SHH STEEL reports actual ladle values on the EN 10204 3.1 MTC for every heat.
| Element | Heat analysis (ASME SA-789 Table 1) |
|---|---|
| Carbon (C) | 0.030 max |
| Manganese (Mn) | 2.50–4.00 |
| Phosphorus (P) | 0.035 max |
| Sulfur (S) | 0.005 max |
| Silicon (Si) | 0.70 max |
| Nickel (Ni) | 3.0–4.5 |
| Chromium (Cr) | 23.0–25.0 |
| Molybdenum (Mo) | 1.00–2.00 |
| Nitrogen (N) | 0.20–0.30 |
| Copper (Cu) | 0.10–0.80 |
Mid-range PREN with Cr ≈24, Mo ≈1.5, N ≈0.25 gives PREN ≈ 33.0 — high for lean duplex, still below mainstream 2205 mid-30s. Copper and manganese ranges are required. SA-789 publishes no PREN minimum for S82441.
Mechanical Properties of SA789 S82441
Table 4 sets tensile and hardness requirements for S82441 after final heat treatment. Lot sampling follows Section 9. Mechanical properties do not apply below 1/8 in. [3.2 mm] OD or 0.015 in. [0.4 mm] wall.
| Property | Requirement (SA-789 Table 4) |
|---|---|
| Wall-/OD-dependent row | Wall <0.40 in. [10 mm]: TS 107 [740], YS 78 [540]; Wall ≥0.40 in.: TS 99 [680], YS 70 [480] |
| Elongation in 2 in. or 50 mm, min | 25% |
| Hardness, max | 290 HBW / 30 HRC / 290 HV |
Table 4 splits by wall: under 0.40 in. [10 mm] — tensile 107 ksi [740 MPa] min, yield 78 ksi [540 MPa] min; at/above 0.40 in. — tensile 99 ksi [680 MPa] min, yield 70 ksi [480 MPa] min; elongation 25% and hardness max 290 HBW / 30 HRC / 290 HV on both. Source: ASME BPVC.II.A-2023 SA-789 Table 4.
Seamless and Welded Tube
ASME SA-789 allows S82441 as seamless tube or as welded tube made with no filler metal. After welding, the finished tube is heat-treated under Table 2, and marking must state the manufacture route with average or minimum wall so receiving can match each length to the purchase order and MTC.
Seamless lots take flaring to at least 10% ID expansion on one end of one tube per lot. Welded lots take flange testing plus reverse flattening on each 1500 ft [450 m] of finished tubing. Tension and hardness apply to both routes. SHH STEEL produces both SA789 S82441 routes and records them on stencil and EN 10204 3.1 MTC.
Dimensions and Tolerances
Order ASME SA789 S82441 by OD × wall (average unless minimum is specified) and length in tube / BWG language, not B36.19 pipe schedules first. Table 5 sets OD-group tolerances; clause 12.2 covers thin-wall ovality.
| OD group (Table 5 summary) | OD tolerance | Avg / Min wall |
|---|---|---|
| Up to ½ in. excl. | ±0.005 in. [0.13 mm] | Avg ±15%; Min +30%/−0% |
| ½ to 1½ in. excl. | ±0.005 in. [0.13 mm] | Avg ±10%; Min +20%/−0% |
| 1½ to 3½ in. excl. | ±0.010 in. [0.25 mm] | Avg ±10%; Min +20%/−0% |
| 3½ to 5½ in. excl. | ±0.015 in. [0.38 mm] | Avg ±10%; Min +20%/−0% |
| 5½ to 8 in. incl. | ±0.030 in. [0.76 mm] | Avg ±10%; Min +20%/−0% |
Source: ASME BPVC.II.A-2023 SA-789 Table 5. SHH STEEL quotes average-versus-minimum wall explicitly on every S82441 enquiry. Write average or minimum wall on every line item so Table 5 percentage bands are unambiguous at receiving.
Equivalent Grades
ASME SA-789 UNS S82441 is the governing tubing designation for this article. Approximate wrought names are chemistry-family hints, not automatic Code substitutes on an SA-789 mill test certificate. Confirm the product standard and tensile row before accepting a commercial nickname on the certificate.
| Designation | Notes |
|---|---|
| ASME SA789 / SA789M UNS S82441 | Governing Code Book tubing designation |
| ASTM A789 / A789M UNS S82441 | Sister ASTM A789 S82441; dual-stencil on request |
| Related lean duplex | SA789 S82011, SA789 S82031, SA789 S32101, SA789 S32304 |
| Standard duplex | SA789 S32205 |
| Plate / sheet | Related duplex plate under A240 / SA240 |
Spell the UNS number and ASME SA789 on the purchase order rather than relying on a shop nickname alone. Confirm the product standard and tensile row before accepting a commercial nickname on the certificate.
Heat Treatment and Delivery Condition
Table 2 requires S82441 solution treatment at 1830 °F [1000 °C] min followed by rapid cooling in air or water. Table 2 lists a minimum of 1830 °F [1000 °C] with rapid cooling in air or water.
Seamless tubes may be quenched after hot forming when temperature is not below the minimum solution-treatment temperature. Skipping or under-cooling risks intermetallics and undermines corrosion performance. SHH STEEL delivers SA789 S82441 only heat-treated per Table 2, with the record on the MTC.
Corrosion Resistance
Estimated PREN near 33.0 makes S82441 one of the stronger lean-duplex pitting options in SA-789, but it is still titled Lean Duplex and is not a silent substitute for SA789 S32205 or SA789 S32750.
Observe SA-789 embrittlement warnings and 475 °C practice notes. Materials review should precede any attempt to stretch this grade outside its PREN and temperature envelope.
Applications of SA789 S82441 Tube
S82441 tube is for lean-duplex duty needing more Mo/N than the leanest grades while avoiding full 2205 nickel cost. Match fluid chemistry and temperature to the PREN estimate and Table 4 floors before freezing the bill of materials.
| Application area | Typical use | Selection note |
|---|---|---|
| Process / water HX | Stronger lean duplex PREN | Confirm vs S32205 |
| Cost-sensitive duplex tubing | Ni 3–4.5% with Mo 1–2% | Wall tensile split |
| Code general-service tube | SA-789 S82441 named | Keep ASME designation |
| Upgrade from 304/316 on SCC | Lean duplex strength | Not seawater default |
If mid-30s PREN is required, use SA789 S32205. For lower-Mo lean see SA789 S82011 or SA789 S32304. Match fluid chemistry and temperature to the PREN estimate and Table 4 floors before freezing the bill of materials.
Weldability
Welding this lean duplex with Mo up to 2% needs qualified procedures — closer to duplex practice than the leanest Mn-rich grades. Mill welded SA-789 product stays autogenous. Control heat input and cool promptly.
SHH STEEL can discuss filler families; the fabricator owns WPS/PQR. Procedure qualification on the actual UNS avoids ferrite and sigma surprises in the heat-affected zone.
Surface Finishes
Standard delivery for SA789 S82441 is heat-treated and descaled/pickled per Section 13, free of excessive mill scale. Bright anneal or Ra-controlled finishes are agreement items that must appear on the order.
SHH STEEL quotes special finishes against the written enquiry rather than assuming them with the grade stamp for S82441. Call any Ra or bright requirement out on the enquiry so mill routing can include it before the heat is reserved.
Inspection and Testing
Testing covers Table 1 chemistry, Table 4 tension and hardness, flare or flange tests by route, reverse flattening for welded tube, and hydro or NDE on each length using duplex hydrostatic factor 64000 (441.2). Manufacturer chooses hydro versus NDE unless the PO locks the method.
Marking shows seamless or welded and wall basis. SHH STEEL 3.1 MTCs tie heat, chemistry, mechanicals, heat treatment, and test method to each length for receiving clearance. Receiving teams should verify hydro-versus-NDE against the purchase order before releasing tube to fabrication.
Packaging and Shipping
S82441 tube ships from SHH STEEL in tagged bundles with end protection matched to length. Tags repeat ASME SA789, grade, route, OD × wall, heat number, and PO reference for export or domestic delivery.
Wrapped bundles or wooden cases are available for bright or small-bore material. Incoterms and MTC flow follow the order acknowledgment. Keep bundle tags legible after ocean transit so port and site receiving can proceed without remarking every length.
Why Choose SHH STEEL
SHH STEEL produces and supplies ASME SA789 UNS S82441 as manufactured lean-duplex Code Book tube, reporting Mn/Cu and wall-dependent tensile floors on the EN 10204 3.1 MTC.
If 2205 is intended, we quote SA789 S32205. Dual marking is available on request. Honest sister-grade advice protects Code stamp integrity when a different UNS would fit the corrosion envelope better.
Supply Capability
SHH STEEL can produce and supply ASME SA789 UNS S82441 against the edition, route, and finish on your enquiry. Capability and Stock / Available sizes follow. Clear enquiry data on OD, wall, and route shortens quotation turnaround for export and domestic Code jobs.
| Item | SHH STEEL capability for S82441 |
|---|---|
| Standard | ASME SA789 / SA789M (dual A789 marking on request) |
| Grade | UNS S82441 |
| Manufacture | Seamless; welded with no filler metal |
| Size range (enquiry) | Common HX / general-service OD × wall (and BWG); other sizes by agreement |
| Wall basis | Average or minimum wall as ordered |
| Delivery condition | Heat-treated 1830 °F [1000 °C] min, rapid cooling in air or water |
| Testing | Heat analysis, tensile, hardness, flare/flange/reverse-flatten; hydro or NDE |
| Documents | EN 10204 3.1 MTC; third-party inspection on request |
Stock / Available sizes — Regular enquiry bands include OD about 12.7–50.8 mm with common BWG / metric walls; larger Table 5 groups by agreement. Cut lengths on request. Send OD × wall, route, and quantity — no invented tonnage lists.
List ASME SA789 UNS S82441, seamless or welded, OD × wall, wall basis, length, and quantity on the enquiry. Clear enquiry data on OD, wall, and route shortens quotation turnaround for export and domestic Code jobs.
FAQ
Conclusion
ASME SA789 UNS S82441 is supplied by SHH STEEL as seamless and welded (no filler metal) lean duplex tubing under the Section II Part A Code Book product standard, heat-treated per Table 2, tested per Section 9, and certified on EN 10204 3.1 MTCs. Confirm OD × wall, wall basis, manufacture route, and any dual SA-789/A789 marking on the purchase order so stencil and certificate match the datasheet. For technical follow-up, contact admin@steelspecs.com.

