🟦 Product Overview
Stainless Steel Round Seamless Pipe is produced by hot rolling or cold drawing without any welding seam, providing superior strength, corrosion resistance, and pressure performance. It is widely used in chemical processing, petrochemical plants, food and beverage systems, heat exchangers, boilers, and other high‑temperature or corrosive environments.
Compared with welded stainless steel pipes, seamless pipes offer higher pressure resistance, better uniformity, and improved reliability for critical applications.
🟦 Available Grades (Austenitic)
304, 304L
316, 316L, 316Ti
310S
321, 347
201, 202
904L
🟦 Manufacturing Processes
Hot Rolled Seamless Pipe – For medium to large diametersCold Drawn / Cold Rolled Seamless Pipe – For high precision and thin‑wall tubesAnnealing & Pickling – Ensures clean, corrosion‑resistant surfaceSurface Finishes: 2B, BA, No.4, HL, mirror polish
🟦 Standards
ASTM A312 / A213 / A269
EN 10216‑5
JIS G3463
DIN / ISO standards
🟦 Product Specifications & Available Sizes
Specification Details Outside Diameter 6–630 mm Wall Thickness 0.5–40 mm Length 6 m / 12 m / custom Type Seamless Finish 2B / BA / No.4 / HL / Mirror Ends Plain End / Beveled End Tolerance As per applicable standard
Regular Size (mm) Ф21×4 Ф87×17.5 Ф121×19 Ф168×19 Ф21×4.5 Ф89×6-12 Ф124×6.5 Ф168×8 Ф22×6.5 Ф89×15 Ф127×10 Ф170×25 Ф25×8 Ф89×17 Ф127×13 Ф172×18 Ф28×8 Ф91×7.5 Ф127×8 Ф180×10 Ф30×10 Ф92×12 Ф130×12 Ф180×18 Ф30×8 Ф95×10 Ф130×18 Ф180×6 Ф32×8 Ф95×12 Ф133×6-12 Ф180×8 Ф34×6 Ф95×16 Ф133×18 Ф183×18 Ф34×8 Ф95×20 Ф140×8-12 Ф185×18 Ф38×10 Ф95×5.5 Ф140×15 Ф185×20 Ф38×8 Ф95×8 Ф140×20 Ф192×18 Ф40×10 Ф100×8.5 Ф142×18 Ф194×10 Ф40×8 Ф100×13 Ф145×18 Ф194×16 Ф42×5-10 Ф102×6-10 Ф146×10 Ф196×16 Ф45×6-12 Ф102×15 Ф146×12 Ф196×24 Ф48×5-10 Ф104×8.5 Ф152×10 Ф200×20 Ф50×8-12 Ф108×6-10 Ф152×12 Ф219×6-12 Ф51×10 Ф108×13 Ф152×14 Ф219×15 Ф55×10 Ф108×15 Ф152×20 Ф245×10 Ф57×6-10 Ф110×6 Ф152×6 Ф250×25 Ф60×6-12 Ф114×6-10 Ф152×8 Ф273×6-12 Ф65×6-12 Ф114×13 Ф159×6-10 Ф273×34 Ф68×6-12 Ф114×17.5 Ф159×12 Ф325×8-10 Ф70×8 Ф116×12 Ф159×15 Ф355×14 Ф70×10 Ф116×8 Ф159×18 Ф377×10 Ф76×6-12 Ф118×2 Ф159×22 Ф406×14 Ф80×8-12 Ф121×6-11 Ф168×10 Ф457×14 Ф83×8-12 Ф121×16 Ф168×12 Ф508×15
🟦 Chemical Composition (Typical for 304)
Element Range (%) C ≤ 0.08 Mn ≤ 2.00 Si ≤ 0.75 P ≤ 0.045 S ≤ 0.030 Cr 18.0–20.0 Ni 8.0–11.0
🟦 Mechanical Properties (Typical for 304)
Property Value Tensile Strength ≥ 520 MPa Yield Strength ≥ 205 MPa Elongation ≥ 40% Hardness ≤ 187 HB
🟦 Primary Industry Usage
Chemical and petrochemical pipelines
Food and beverage processing
Heat exchangers and boilers
Machinery and equipment manufacturing
Pharmaceutical and sanitary systems
High‑temperature and corrosive environments
🟦 Why Use Stainless Steel Round Seamless Pipe
No weld seam → higher pressure resistance
Excellent corrosion and oxidation resistance
High strength and long service life
Smooth, clean, hygienic surface
Suitable for high‑temperature and corrosive media
🟦 Why Choose WelSteels
Full range of austenitic stainless seamless grades
High‑precision cold‑drawn and hot‑rolled production
Advanced annealing and polishing lines
SGS / BV third‑party inspection available
Custom cutting, beveling, polishing, fabrication
Export‑grade seaworthy packaging
Fast delivery from stock and mill production
International Stainless-Steel Standard
No China Japan America Korea Germany India Australia Taiwan, China GB JIS ASTM UNS KS DIN BIS AS CNS Austenitic Stainless Steel 1 12Cr17Mn6Ni5N SUS201 201 S20100 STS201 1.4372 10Cr17Mn6Ni4N20 201-2 201 2 12Cr18Mn9Ni5N SUS202 202 S20200 STS202 1.4373 – – 202 3 12Cr17Ni7 SUS301 301 S20200 STS301 1.4319 10Cr17Ni7 301 301 4 06Cr19Ni10 SUS304 304 S30400 STS304 1.4301 07Cr18Ni9 304 304 5 022Cr19Ni10 SUS304L 304L S30403 STS304L 1.4306 02Cr18Ni11 304L 304L 6 06Cr19Ni10N SUS304N1 304N S30451 STS304N1 1.4315 – 304N1 304N1 7 06Cr19Ni9NbN SUS304N2 XM21 S30452 STS304N2 – – 304N2 304N2 8 022Cr19Ni10N SUS304LN 304LN S30453 STS304LN – – 304LN 304LN 9 10Cr18Ni12 SUS305 305 S30500 STS305 1.4303 – 305 305 10 06Cr23Ni13 SUS309S 309S S30908 STS309S 1.4833 – 309S 309S 11 06Cr25Ni20 SUS310S 310S S31008 STS310S 1.4845 – 310S 310S 12 06Cr17Ni12Mo2 SUS316 316 S31600 STS316 1.4401 04Cr17Ni12Mo2 316 316 13 06Cr17Ni12Mo2Ti SUS316Ti 316Ti S31635 – 1.4571 04Cr17Ni12MoTi20 316Ti 316Ti 14 022Cr17Ni12Mo2 SUS316L 316L S31603 STS316L 1.4404 ~02Cr17Ni12Mo2 316L 316L 15 06Cr17Ni12Mo2N SUS316N 316N S31651 STS316N – – 316N 316N 16 022Cr17Ni13Mo2N SUS316LN 316LN S31653 STS316LN 1.4429 – 316LN 316LN 17 06Cr18Ni12Mo2Cu2 SUS316J1 – – STS316J1 – – 316J1 316J1 18 022Cr18Ni14Mo2Cu2 SUS316J1L – – STS316J1L – – – 316J1L 19 06Cr19Ni13Mo3 SUS317 317 S31700 STS317 – – 317 317 20 022Cr19Ni13Mo3 SUS317L 317L S31703 STS317L 1.4438 – 317L 317L 21 06Cr18Ni11Ti S SUS321 321 S32100 STS321 1.4541 04Cr18Ni10Ti20 321 321 22 06Cr18Ni11Nb SUS347 347 S34700 STS347 1.4550 04Cr18Ni10Nb40 347 347 Duplex Stainless Steel 1 – SUS329J1 329 S32900 STS329J1 1.4477 – 329J1 – 2 022Cr23Ni5Mo3N – S32205 F60 – 1.4462 – 2205 2205 3 022Cr25Ni7Mo4N – S32750 F53 – 1.4410 – 2507 2507 Ferrite stainless steel 1 06Crl3Al SUS405 405 S40500 STS405 1.4002 04Cr13 405 405 2 022Cr11Ti SUH409 409 S40900 STS409 1.4512 – 409L 409L 3 022Cr12 SUS410L – – STS410L – – 410L 410L 4 10Cr17 SUS430 430 S43000 STS430 1.4016 05Cr17 430 430 5 10Cr17Mo SUS434 434 S43400 STS434 1.4113 – 434 434 6 022Cr18NbTi – – S43940 – 1.4509 – 439 439 7 019Cr19Mo2NbTi SUS444 444 S44400 STS444 1.4521 – 444 444 Martensitic Stainless Steel 1 12Cr12 SUS403 403 S40300 STS403 – – 403 403 2 12Cr13 SUS410 410 S41000 STS410 1.4006 12Cr13 410 410 3 20Cr13 SUS420J1 410 S42000 STS420J1 1.4021 20Cr13 420 420J1 4 30Cr13 SUS420J2 – – STS420J2 1.4028 30 Cr13 420J2 420J2 5 68Cr17 SUS440A 440A S44002 STS440A – – 440A 440A
