309 / 309S / 310 / 310S Stainless Steel Pipes are high‑temperature austenitic stainless steels designed for service in environments requiring exceptional oxidation resistance and mechanical strength at elevated temperatures.
309 / 309S
Higher chromium and nickel than 304/316
Excellent oxidation resistance up to 1000–1100°C
309S has lower carbon for improved weldability
310 / 310S
Even higher Cr & Ni content
Outstanding oxidation resistance up to 1100–1200°C
310S has lower carbon to reduce carbide precipitation
These grades are widely used in industrial furnaces, burners, heat treatment fixtures, petrochemical heaters, and high‑temperature structural components.
Key Advantages:
Excellent oxidation resistance at high temperatures
High creep strength and thermal stability
Good weldability (S‑grades preferred for welding)
Suitable for continuous high‑temperature service
🟧 Standards
ASTM A312 / A312M
ASTM A213
EN 10216‑5
JIS G3463
GB/T 14976
🟧 Grades
309 (UNS S30900)
309S (UNS S30908)
310 (UNS S31000)
310S (UNS S31008)
🟧 Product Specifications & Available Sizes
Outer Diameter (OD)
Seamless: 6–530 mm
Welded: 12–630 mm
Wall Thickness (WT)
0.5–30 mm
Length
6 m / 12 m / custom
Type
Seamless (Cold Drawn / Hot Rolled)
Welded (ERW / TIG / Laser Welded)
Surface Finish Options
Pickled
Annealed
Polished (180–400 grit)
Heat‑resistant finish
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
（ASTM A312）
309
Element
Content (%)
C
≤ 0.20
Si
≤ 1.00
Mn
≤ 2.00
P
≤ 0.045
S
≤ 0.030
Cr
22.0–24.0
Ni
12.0–15.0
309S
Element
Content (%)
C
≤ 0.08
Si
≤ 1.00
Mn
≤ 2.00
P
≤ 0.045
S
≤ 0.030
Cr
22.0–24.0
Ni
12.0–15.0
310
Element
Content (%)
C
≤ 0.25
Si
≤ 1.50
Mn
≤ 2.00
P
≤ 0.045
S
≤ 0.030
Cr
24.0–26.0
Ni
19.0–22.0
310S
Element
Content (%)
C
≤ 0.08
Si
≤ 1.50
Mn
≤ 2.00
P
≤ 0.045
S
≤ 0.030
Cr
24.0–26.0
Ni
19.0–22.0
🟧 Mechanical Properties
The mechanical properties of the four grades are essentially identical.
Property
Requirement
Tensile Strength
≥ 520 MPa
Yield Strength
≥ 205 MPa
Elongation
≥ 40%
Hardness
≤ 217 HB
🟧 Physical Properties
Property
309 / 309S
310 / 310S
Density
7.98 g/cm³
7.98 g/cm³
Melting Point
1390–1440°C
1400–1450°C
Thermal Conductivity
14.2 W/m·K
14.2 W/m·K
Electrical Resistivity
0.78 μΩ·m
0.80 μΩ·m
🟧 Manufacturing Processes
Hot Rolling
Cold Drawing
TIG Welding
Laser Welding
High‑Temperature Annealing
Pickling
Heat‑resistant finishing
Non‑destructive Testing (Eddy Current / Hydrostatic)
