01
904L Seamless Tube
904L seamless tube carries no longitudinal weld, so no heat-affected zone exists to initiate corrosion. We produce it to ASTM A213 / ASME SA-213 for acid plant duty and exchanger bundles.
Stainless Steel 904L Tube Manufacturer in India
MLTI Private Limited (Moonlight Tube Industries) is a 904L stainless steel tube manufacturer, supplier and exporter based in Gujarat, India, producing stainless tubes since 2008 at a plant rated at nearly 8,000 MT a year.
Stainless steel 904L tube is a low-carbon super austenitic tube designated UNS N08904 and W.Nr. 1.4539. We produce seamless tubing to ASTM A213 / ASME SA-213 and welded tubing to ASTM A249 / ASME SA-249, with general-service 904L stainless steel tubing supplied to ASTM A269. A seamless 904L tube starts from a pierced hollow and finishes cold-drawn, so the wall runs continuously down the full length. Welded tube costs less at the same diameter, and ASTM A249 addresses the seam with a reverse-bend test that seamless tube never requires; where the wall is 10 % or more of the outside diameter, the wall is 3.4 mm or thicker, or the outside diameter is below 9.5 mm, the reverse flattening test of ASTM A1016 applies instead. Both routes leave our line solution annealed and quenched. Acid-plant coils and high-pressure exchanger bundles take seamless, welded covers for the larger diameters and thinner walls on chloride cooling duty. The grade combines 23.0–28.0% nickel, 19.0–23.0% chromium, 4.0–5.0% molybdenum and a 1.00–2.00% copper addition. Copper provides resistance to sulphuric acid across a wide band of concentrations. High nickel resists chloride stress corrosion cracking; molybdenum limits pitting in warm seawater.
Minimum tensile strength is 490 MPa (71 ksi) and minimum yield strength is 215 MPa (31 ksi), solution-annealed. Round 904L tubes are available in outside diameters from 12.7 mm to 101.6 mm, with wall thicknesses of 19 BWG to 10 BWG (1.07 mm to 3.40 mm) on seamless tube and 19 SWG to 10 SWG (1.016 mm to 3.251 mm) on welded tube. Acid plants, fertiliser process lines, and seawater coolers specify this material. The works hold ISO 14001 and 45001 certifications with EIL, IBR, and PED approvals, and each lot is shipped with an EN 10204 3.1 certificate.
Stainless Steel 904L Tube Specifications
Round 904L tubes conform to ASTM A213 in seamless form and to ASTM A249 in welded form, with ASTM A269 covering both forms in general service. The table provides the details below.
| Parameter | Value |
|---|---|
| Applicable standards | ASTM A213/ ASME SA-213: Seamless Ferritic and Austenitic Alloy-Steel Boiler, Superheater, and Heat-Exchanger Tubes, ASTM A249 / ASME SA-249: Welded Austenitic Steel Boiler, Superheater, Heat Exchanger, and Condenser Tubes. ASTM A269: Seamless and Welded Austenitic Stainless Steel Tubing for General Service |
| Manufacturing process | Seamless and welded (autogenous, no filler metal) (ERW) |
| Sections | Round to ASTM A213 / A249 / A269. Square and rectangular hollow sections fall outside these three standards and are supplied as mechanical tubing to a specification agreed at the order stage. |
| Outside diameter, round | 12.7 mm to 101.6 mm (1/2" to 4") |
| Wall thickness, round | 1.07 mm to 3.40 mm (19 SWG to 10 SWG) |
| Length | Cut to the ordered length |
| Delivery condition | Solution annealed at 1100 °C (2000 °F) minimum, water quenched or rapidly cooled by other means |
| Finish | Mill finish; annealed and pickled; bright annealed; polished to order |
| End type | Plain end, cut square |
SS 904L Tube Chemical Composition
SS 904L seamless tube chemistry is fixed by ASTM A213 / ASME SA-213, which specify identical limits for UNS N08904. Copper and molybdenum ranges appear in the table below.
| Element | Composition, % by mass |
|---|---|
| Carbon (C) | 0.020 max |
| Manganese (Mn) | 2.00 max |
| Phosphorus (P) | 0.040 max |
| Sulphur (S) | 0.030 max |
| Silicon (Si) | 1.00 max |
| Chromium (Cr) | 19.0–23.0 |
| Nickel (Ni) | 23.0–28.0 |
| Molybdenum (Mo) | 4.0–5.0 |
| Copper (Cu) | 1.00–2.00 |
| Nitrogen (N) | 0.10 max |
| Iron (Fe) | Balance |
Molybdenum gives 904L higher pitting resistance than 316L; copper is what separates 904L from 317L in reducing-acid duty.
SS 904L Tube Mechanical Properties
The table below shows the room-temperature minima for tensile, yield, and elongation, along with the hardness ceiling from ASTM A213 / ASME SA-213.
| Property | Value/Unit |
|---|---|
| Tensile strength, min | 490 MPa (71 ksi) |
| Yield strength, 0.2% offset, min | 215 MPa (31 ksi) |
| Elongation in 50 mm (2 in.), min | 35% |
| Hardness, max | 90 HRB / 200 HV / 192 HBW |
| Solution treatment temperature, min | 1100 (2000)°C (°F) |
Austenite is retained to cryogenic temperatures, so the alloy keeps its toughness in cold service.
904L Tube Equivalent Grades and Designations
National standards across Europe, Asia, and North America specify 904L SS tube under various regional designations. The table below lists equivalent grade marks for cross-referencing engineering drawings across different global standards.
| Country / Standard | Designation |
|---|---|
| Europe (EN) | 1.4539, X1NiCrMoCu25-20-5 |
| UNS | N08904 |
| Germany (Werkstoff) | W.Nr. 1.4539 |
| Japan (JIS) | SUS 904L |
| United Kingdom (BS) | 904S13 |
| France (AFNOR) | Z2CNDU 25-20 |
| Sweden (SS) | SS 2562 |
| South Korea (KS) | STS 317J5L |
| China (GB/T) | 015Cr21Ni26Mo5Cu2 |
Types and Forms of 904L Stainless Steel Tube
Two manufacturing processes and three section profiles are available. Seamless, welded (ERW) construction covers the pressure and cost range; round, square, and rectangular profiles cover the fabricated side of the range.
02
904L Welded (ERW) Tube
A welded 904L tube starts as a slit strip, formed into a round tube and closed by electric resistance without filler metal, so weld chemistry matches the parent alloy. ASTM A249 / ASME SA-249 requires cold work across the weld before solution annealing. Larger diameters suit this route.
03
904L Round Tube
The round section is the highest-volume profile, produced from 12.7 mm to 101.6 mm outside diameter across six BWG gauges seamless and six SWG gauges welded. Exchanger bundles, condenser tubes, instrumentation tubes, and hydraulic tube runs specify it.
04
904L Square Tube
The square 904L tube is a welded box section, produced to the size and wall stated on the order. It sits outside the scope of ASTM A213, A249, and A269, so the specification, tolerance, and test scope are agreed upon at the order stage. It goes into frames, supports, and handling structures in acid and chloride process areas.
05
904L Rectangular Tube
The rectangular 904L tube follows the same welded route as the square section and is specified where a member carries a bending load about one axis. Like the square section, it sits outside ASTM A213, A249, and A269; dimensions, wall thickness, and test scope are agreed at the order stage.
904L Tubing Sizes
Sizes of stainless steel 904L tubes range from 12.7 mm to 101.6 mm in outside diameter across eleven nominal sizes, with seamless walls set by BWG gauge and welded walls by SWG gauge. Diameters against the six-gauge walls are given in the table below, in millimetres.
Seamless 904L Tube Size Chart
| Size | OD (mm) | 10 BWG (3.40 mm) Weight/MTR | 12 BWG (2.77 mm) Weight/MTR | 14 BWG (2.11 mm) Weight/MTR | 16 BWG (1.65 mm) Weight/MTR | 18 BWG (1.25 mm) Weight/MTR | 19 BWG (1.07 mm) Weight/MTR |
|---|---|---|---|---|---|---|---|
| 1/2" | 12.7 | 0.78 | 0.68 | 0.55 | 0.45 | 0.35 | 0.31 |
| 5/8" | 15.875 | 1.05 | 0.89 | 0.72 | 0.58 | 0.45 | 0.39 |
| 3/4" | 19.05 | 1.31 | 1.11 | 0.88 | 0.71 | 0.55 | 0.47 |
| 1" | 25.4 | 1.85 | 1.55 | 1.21 | 0.97 | 0.74 | 0.64 |
| 1 1/4" | 31.75 | 2.38 | 1.98 | 1.54 | 1.23 | 0.92 | 0.81 |
| 1 1/2" | 38.1 | 2.91 | 2.41 | 1.87 | 1.48 | 1.13 | 0.97 |
| 2" | 50.8 | 3.98 | 3.28 | 2.53 | 2.00 | 1.52 | 1.31 |
| 2 1/2" | 63.5 | 5.04 | 4.15 | 3.19 | 2.52 | 1.91 | 1.64 |
| 3" | 76.2 | 6.11 | 5.01 | 3.85 | 3.04 | 2.30 | 1.98 |
| 3 1/2" | 88.9 | 7.18 | 5.88 | 4.51 | 3.55 | 2.69 | 2.31 |
| 4" | 101.6 | 8.24 | 6.75 | 5.17 | 4.07 | 3.08 | 2.65 |
ERW 904L Tube Size Chart
| Size | OD (mm) | 10 SWG (3.25 mm) Weight/Mtr | 12 SWG (2.64 mm) Weight/Mtr | 14 SWG (2.03 mm) Weight/Mtr | 16 SWG (1.63 mm) Weight/Mtr | 18 SWG (1.22 mm) Weight/Mtr | 19 SWG (1.02 mm) Weight/Mtr |
|---|---|---|---|---|---|---|---|
| 1/2" | 12.7 | 0.75 | 0.65 | 0.55 | 0.45 | 0.34 | 0.29 |
| 5/8" | 15.875 | 1.01 | 0.86 | 0.72 | 0.58 | 0.44 | 0.37 |
| 3/4" | 19.05 | 1.26 | 1.06 | 0.88 | 0.71 | 0.53 | 0.45 |
| 1" | 25.4 | 1.76 | 1.47 | 1.21 | 0.97 | 0.72 | 0.61 |
| 1 1/4" | 31.75 | 2.27 | 1.88 | 1.54 | 1.23 | 0.91 | 0.76 |
| 1 1/2" | 38.1 | 2.77 | 2.29 | 1.88 | 1.49 | 1.10 | 0.92 |
| 2" | 50.8 | 3.78 | 3.11 | 2.54 | 2.01 | 1.48 | 1.24 |
| 2 1/2" | 63.5 | 4.79 | 3.93 | 3.20 | 2.53 | 1.85 | 1.55 |
| 3" | 76.2 | 5.79 | 4.75 | 3.86 | 3.05 | 2.23 | 1.87 |
| 3 1/2" | 88.9 | 6.80 | 5.57 | 4.52 | 3.57 | 2.61 | 2.18 |
| 4" | 101.6 | 7.81 | 6.39 | 5.18 | 4.09 | 2.99 | 2.50 |
Sizes outside that band are produced to order, with tolerances taken from the standard specified on the order.
904L Stainless Steel Tube Industrial Applications
904L tube is specified in six industries where 316L corrosion resistance falls short. Each industry and the equipment involved are covered below.
Chemical Processing and Acid Plants
This grade is primarily used for sulphuric, phosphoric, and acetic acid service. 904L tubes are commonly used in reactor coils, dosing lines, and scrubber internals because the copper addition helps them withstand the sulphuric acid concentrations these units range.
Fertiliser Production
Phosphoric acid concentrators handle hot acid loaded with fluoride and chloride. 904L heat exchanger tube goes into the evaporator and cooler bundles here, where lower-alloyed austenitic tube suffers rapid wall loss.
Oil and Gas Refining
Refinery overhead condensers, sour water strippers, and amine coolers see wet chlorides. 904L instrumentation tubes and hydraulic tubes carry impulse fluid offshore, where nickel content resists chloride stress corrosion cracking.
Marine and Seawater Cooling
904L condenser tube serves seawater intake coolers and desalination heat recovery, with 4.0–5.0% molybdenum raising resistance to crevice attack under deposits, gaskets, and tube-sheet joints.
Pulp and Paper Bleaching
Chlorine dioxide bleach stages combine chloride, low pH, and elevated temperature. Bleach tower cooling coils and washer liquor circuits take 904L tube, since the alloy resists pitting and acid attack.
Power Generation and Flue-Gas Desulphurisation
Absorber spray headers and quench coils use 904L tube, where the chloride concentrated in the recirculating slurry and the low pH shorten the service life of standard austenitic grades such as 316L.
Welding and Heat Treatment of 904L Stainless Steel Tubes
Welding 904L stainless steel tubes does not require preheat or post-weld heat treatment. An over-alloyed nickel-base filler compensates for molybdenum segregation in the weld metal, and restrained joints are avoided because austenitic weld metal is sensitive to hot cracking. Tubes cold-worked after annealing are re-solution treated at a minimum of 1100 °C (2000 °F) and quenched, restoring the annealed austenitic structure and the corrosion resistance degraded by cold work. Sigma and chi phases come from prolonged exposure in the 650–950°C range rather than from cold work itself, and both cut acid resistance once formed.
Stainless Steel 904L Tube Shipping and Packaging
Packing is set up for sea freight and long transit times.
- Tube is bundled in hexagonal packs, strapped, and end-capped to protect the bore, and is wrapped in polythene and cased for export.
- Export shipments move on FOB or CFR terms to Brazil, Vietnam, Turkey, and Europe.
- Each bundle is tagged with grade, size, gauge, and heat number.
- Marking, documentation, and cut lengths are agreed upon at the order stage.
904L Stainless Steel Tube Price in India
The price of 904L SS in India is roughly ₹180–₹1,500 per kg, and in the USA it is about US$8.50–19/kg, quoted per kilogram, and it moves with nickel, molybdenum, and copper input costs. Six variables determine the figure: outside diameter, wall gauge, order quantity, surface finish, manufacturing route, and governing standard.
Why Buy 904L Stainless Steel Tube From MLTI?
Buyers return to Moonlight Tubes for certified material, approved grades and stock that ships on schedule. Every order is backed by documented quality, a wide size range and delivery commitments we hold to.
Quality Certification
01
IBR & EIL Approved
02
Why
Choose Us
03
Wide Range of Grades & Sizes
04
Timely Global Delivery
Frequently Asked Questions About 904L Stainless Steel Tube
ASTM A213 / ASME SA-213 covers seamless 904L stainless steel tube; ASTM A249 / ASME SA-249, the welded form; and ASTM A269, general-service tubing. ASTM B677 no longer carries UNS N08904.
The 904L stainless steel vs 316L choice turns on the medium. In any 904L vs 316L comparison, acids, warm seawater, and chloride cracking risk call for 904L; for general duty, 316L costs less.
The 904L stainless steel price in India is roughly ₹180–₹1,500 per kg, and in the USA it is roughly US$8.50–19/kg, quoted per kilogram against the day's nickel, molybdenum, and copper rates. Diameter, gauge, quantity, and finish all affect the price.
904L tube is UNS N08904 in the United States, 1.4539 in Europe, SUS 904L in Japan, 904S13 in the United Kingdom and 015Cr21Ni26Mo5Cu2 in China.
904L tube welds readily by TIG and plasma, with no preheat or post-weld heat treatment. Use an over-alloyed nickel-base filler to limit hot cracking.
Round SS 904L tube runs 12.7 mm to 101.6 mm outside diameter, in walls from 1.07 mm (19 BWG) to 3.40 mm (10 BWG) seamless and 1.016 mm (19 SWG) to 3.251 mm (10 SWG) welded.