Furnace Muffles and Radiant Heating
Heat-treatment furnaces run muffle tubes and radiant tubes in seamless 309, relying on its high chromium and nickel content to limit oxidation and scaling of the wall facing the burner flame.
UNS S30900 / W.Nr. 1.4828
Stainless Steel 309 Seamless Tubes Manufacturer in Thailand
We are Thaida Stainless Steel Manufacturing (Thailand) Co., Ltd., a manufacturer of stainless steel 309 seamless tubes based in Ban Bueng, Chonburi, Thailand, supplying heat-resisting tubing for furnaces, boilers and heat recovery equipment. Identified as UNS S30900 and cross-referenced to W.Nr. 1.4828, the grade brings high chromium and nickel to our stainless steel seamless tubes range for service in hot oxidizing gas. Our office in Bang Phli, Samut Prakan, handles drawings and quotations.
Stainless Steel 309 seamless tubeUNS S30900 / W.Nr. 1.4828
- 6.35 to 257 mmOutside diameter
- 0.89 to 12.7 mmWall thickness
- Up to 22 mLength
- EN 10204 3.1Test certificate
EN 10204 3.1 certificate / 3.2 on request
Specifications of SS 309 Seamless Tube
Each 309 stainless steel seamless tube is produced to the OD and wall thickness stated on your order. Hot-worked shells are drawn cold to final size, solution annealed, then pickled and straightened.
- Grade
- 309
- UNS S30900 (cross-reference W.Nr. 1.4828)
- Outside Diameter
- 6.35 to 257 mm
- Wall Thickness
- 0.89 to 12.7 mmordered as minimum or average
- Length
- Straight to 22 mcut lengths on request
- Form
- Seamless
- Manufacturing Route
- 1Solid billet hot pierced
- 2Hot worked
- 3Then cold drawn to final size
- Heat Treatment
- Solution anneal in the 1040 to 1150°C (1900 to 2100°F) band, then rapid cooling
- Surface Condition
- Pickled and straightened
- Test Certificate
- EN 10204 3.13.2 on request
ASTM A213 / ASME SA-213 governs seamless ferritic and austenitic tubing for boiler, superheater and heat-exchanger duty and lists TP309S (UNS S30908) and TP309H (UNS S30909), the nearest grades, but plain 309 has no row of its own. We therefore produce each UNS S30900 seamless tube to the chemistry and annealed properties tabulated below. Furnace gas lines and other piping in the grade, ordered by NPS and schedule, are supplied as stainless steel 309 seamless pipes.
Every heat of seamless S30900 stainless steel tube is supplied with an EN 10204 3.1 (3.2 on request) material test certificate. With it come a 100% PMI record, the raw material certificate, the heat treatment charts and a size and surface roughness report. Eddy current, ultrasonic or hydrostatic test results are reported on our manufacturer test certificate, and your order can name the method your code calls for. Hardness, intergranular corrosion, pitting corrosion and grain size tests are added when the order specifies them, and third-party inspection is available on request.
Chemical Composition of Seamless Stainless Steel 309 Tube
Nickel at 12.00 to 15.00% and chromium at 22.00 to 24.00% are what let 309 resist scaling in hot oxidizing gas. The heat analysis of each seamless 1.4828 stainless steel tube is reported against the limits below.
- CrChromium, 22.00 to 24.00
- NiNickel, 12.00 to 15.00
- MnManganese, ≤ 2.00
- SiSilicon, ≤ 1.00
- CCarbon, ≤ 0.20
UNS S30900309
| Element | UNS S30900 (%) |
|---|---|
| C (Carbon) | ≤ 0.20 |
| Mn (Manganese) | ≤ 2.00 |
| P (Phosphorus) | ≤ 0.045 |
| S (Sulfur) | ≤ 0.030 |
| Si (Silicon) | ≤ 1.00 |
| Cr (Chromium) | 22.00 to 24.00 |
| Ni (Nickel) | 12.00 to 15.00 |
Mechanical Properties of 309 Stainless Steel Seamless Tube
The minimums below apply to tube delivered solution annealed and rapidly cooled. Each heat's tensile, yield and elongation results are printed on the certificate beside them.
| Property, Annealed Condition | Minimum |
|---|---|
| Tensile Strength | 550 MPa (80 ksi) |
| Yield Strength | 205 MPa (30 ksi) |
| Elongation | 40% |
Stainless Steel 309 Equivalent Designations
National standards list Stainless Steel 309 under the designations below.
- UNSS30900
- AISI (USA)309
- W.Nr. (Germany)1.4828
- EN steel nameX15CrNiSi20-12
- JIS (Japan)SUS 309
- BS (UK)309S24
- GOST (Russia)20KH20N14S2
- AFNOR (France)Z17CNS20-12
Treat the European entries as a cross-reference: a seamless WNR 1.4828 tube named on a European drawing is quoted as the UNS S30900 seamless tube made to the limits above, so state the UNS number on your order.
Seamless WNR 1.4828 Tube Sizes and Tolerances
Our mill draws stainless steel 309 seamless tubes in ODs of 6.35 to 257 mm and wall thicknesses of 0.89 to 12.7 mm, and supplies them in straight lengths to 22 m. Our seamless 309 tubing is held to the same permitted variations we apply to our ASTM A213 seamless tubing, shown below for the larger furnace and heat recovery sizes. For ODs over 225 mm, the tolerance is agreed with you when we quote.
| Specified OD (mm) | Cold-Finished OD Variation (mm) |
|---|---|
| 50 to under 65 | ±0.25 |
| 65 to under 75 | ±0.3 |
| 75 to 100 | ±0.38 |
| Over 100 to 200 | +0.38 / -0.64 |
| Over 200 to 225 | +0.38 / -1.14 |
Except on thin-wall sizes, these figures include out-of-roundness, and they apply before the tube is bent, swaged or expanded.
Choosing Among Grades 309, 310 and 310S
Where a furnace or recuperator needs more alloy than 309 provides, stainless steel 310S seamless tubes carry 19.0 to 22.0% nickel and 24.0 to 26.0% chromium, with carbon held to 0.08% max. Stainless steel 310 seamless tubes share that chromium and nickel band but allow up to 0.25% carbon. Of the three, seamless stainless steel 309 tube carries the least nickel and therefore the lowest alloy cost.
Applications of UNS S30900 Seamless Tube
Seamless grade 309 tubing is chosen for equipment exposed to combustion gases and hot oxidizing atmospheres, from furnace internals to boiler and flue gas plant.
Thermocouple Sheaths in Furnace Walls and Flues
Thermocouple protection tubes in seamless 309 shield temperature sensors inserted through furnace walls and flue passages, and each one is cut to your probe length.
Boiler Air Preheaters and Burner Throats
Boiler makers use seamless 309 for air preheater tube sections, superheater and reheater support tubes, and the burner throat and flame guide tubes that sit closest to the combustion zone.
Heat Recovery Units
Heat recovery tubes in seamless 309 take up energy from hot exhaust and flue gas, with the outer surface facing combustion by-products and high-temperature corrosive gases throughout each campaign.
Black Liquor Recovery Boilers
Pulp and paper mills install seamless 309 as recovery boiler tubing for black liquor firing and in pulp drying equipment, where hot process gas and pulping chemicals reach the same tube.
FGD Gas Reheaters
Flue gas desulfurization units pass scrubbed flue gas over seamless 309 gas reheater tubing to raise its temperature before the gas is discharged through the stack.
Food Processing Steam and Burner Assemblies
Food processing plants specify seamless 309 for steam distribution tubes and for the burner and radiant tube assemblies used to heat process equipment.
Shipping and Packaging of Seamless 1.4828 Stainless Steel Tube
Packing
Tubes bundled by size and wrapped, or packed in wooden cases for long and small-OD lengths.
Marking
Each tube stenciled with UNS S30900, heat number, OD and wall, with your project tags on request.
Bore protection
Plastic caps fitted on both ends of every tube.
Cut lengths
Tubes trimmed to the dimensions on your furnace or exchanger drawing, or shipped in full mill lengths.
Incoterms
FOB, CIF or CFR, fixed on each quotation.
Destinations
Thailand, Singapore, Malaysia, Vietnam, Indonesia, the Philippines and India.
Price of Seamless S30900 Stainless Steel Tube
Our indicative range for stainless steel 309 seamless tubes is USD 4.5 to 8.5 per kg. A nickel content of 12.00 to 15.00% drives the alloy cost, and because 309 seamless tube is stocked less widely than 304 or 316L, lot size and mill scheduling move a quotation within the band as much as OD, wall and length do. For a firm figure, send us your sizes and quantities.
Indicative price, Stainless Steel 309 Seamless Tubes
USD 4.5 to 8.5 per kg
Indicative only. Send your sizes and specification to Thaida for a firm quotation.
- Outside diameter
- Wall thickness
- Length
- Quantity
- Nickel price
Order Seamless 309 Tube from Our Ban Bueng Mill
Stainless steel 309 seamless tubes are drawn, annealed and tested at our factory at 154 Moo.1 Map Phai, Ban Bueng, Chonburi 20170, Thailand. Inquiries, tube drawings and order confirmations are handled from 89/18 Moo.15 Enterprize Park, Bangna-Trad Road, Bang Kaeo, Bang Phli, Samut Prakan 10540, Thailand. Each quotation gives a dispatch date for every line item.
Factory154 Moo.1 Map Phai, Ban Bueng,
Chonburi 20170, Thailand
Chonburi 20170, Thailand
Office89/18 Moo.15 Enterprize Park, Bangna-Trad Road,
Bang Kaeo, Bang Phli, Samut Prakan 10540, Thailand
Bang Kaeo, Bang Phli, Samut Prakan 10540, Thailand
Exporting to
- Singapore
- Malaysia
- Vietnam
- Indonesia
- Philippines
- India
Frequently Asked Questions on 309 Seamless Tubing
How even is the wall around a heavy 309 seamless tube?
Within ±10% of the mean. For tube of 50 mm OD and over with walls of 5.6 mm and over, the wall at any one cross section stays within ±10% of that section's actual mean wall, the limit we also hold on our A213 seamless tubing.
Which OD limits hold on small-bore 309 seamless tube for thermocouple sheaths?
Cold-finished tube under 25 mm OD is held to +0.1 / -0.11 mm, and 25 to 40 mm OD inclusive to ±0.15 mm, the permitted variations we apply to our A213 seamless tubing. Below 50.8 mm OD, the maximum and minimum diameter at any cross section also stay within ±0.25 mm of nominal.
How far above a minimum wall can 309 seamless tube run?
Up to 20% over the ordered minimum at 38.1 mm OD or smaller, and up to 22% on bigger sizes, but never below it. An average-wall order works differently: cold-formed tube must then sit within ±10% of the stated wall in either direction.
Is 309 seamless tube magnetic?
No. In the solution-annealed condition in which it is delivered, 309 is an austenitic, non-magnetic stainless steel. To confirm the grade itself, rely on the 100% PMI results supplied with each delivery.
Why does a heat recovery bundle call for grade 309 rather than 304?
Because 309 carries more alloy: its nickel range of 12.00 to 15.00% compares with 8.0 to 11.0% for 304, and its chromium range of 22.00 to 24.00% with 18.0 to 20.0%. That extra chromium and nickel gives 309 greater resistance to oxidation in hot exhaust and flue gas, where a heat recovery bundle spends its service life.
Can 309 seamless tube cut to a furnace pitch ever arrive short?
No. Cut lengths are plus only, as on our A213 seamless tubing: cold-finished tube takes +3 mm / 0 below 50.8 mm OD and +5 mm / 0 from 50.8 mm OD upward. Cuts beyond 7.3 m earn 3 mm more plus allowance per extra 3 m, or any part of one, never over 13 mm extra.
Can flattening and flare tests be ordered for 309 seamless tube expanded into a tube sheet?
Yes, on request. Flattening and flare results show how the tube end handles the deformation of expanding into a tube sheet, and they are reported on the manufacturer test certificate together with any bend test you add.
Request a Quote for Stainless Steel 309 Seamless Tubes
or email sales@thaida.co.th