ASME SA213 TP321 Stainless Steel Seamless Tube For Superheater

If you are looking for ASME SA213 TP321 stainless steel seamless tubes for superheaters with stable high-temperature performance, precise dimensional control, full material traceability, and reliable export service, GNEE Steel can supply tubing that fully complies with ASME SA213, ASTM A213, and DIN EN requirements. Our products are designed to solve common operational problems such as intergranular corrosion after welding, high-temperature creep deformation, inconsistent dimensions, and surface defects.

 

GNEE supplies high-quality TP321 stainless steel heat exchanger tubes produced with titanium stabilization, which provides stronger resistance to sensitization and higher creep strength compared with TP304 and TP316L. The material supports continuous service temperatures up to 816 °C, with short-term oxidation resistance reaching 870 °C. Tube dimensional accuracy is strictly controlled, with OD tolerance within ±0.10 mm and wall thickness tolerance within ±10%, while the internal and external surface roughness Ra ≤ 1.6 µm improves steam flow efficiency and reduces fouling.

Our TP321 stainless steel round tubes are manufactured through cold drawing or cold rolling, followed by solution annealing and pickling-passivation, ensuring a uniform austenitic microstructure and clean oxide-free surfaces. Products are available in straight tubes and U-bend tubes, with surface finishes including bright annealed (BA) or pickled surfaces. The tubes typically provide tensile strength ≥ 515 MPa and yield strength ≥ 205 MPa, and in oxidizing environments the maximum continuous service temperature can reach 870 °C (1600 °F). These characteristics make TP321 seamless tubes highly suitable for superheaters, boilers, refinery heaters, and various high-temperature process equipment.

 

Specification:

Grades	321; 321H; 1.4541; 1.4878
Type	U-bend & Straight seamless tube
Outer Diameter	1/4'' to 2'' or custom size
Wall Thickness	BWG25;BWG22;BWG20;BWG18;BWG16;BWG14;BWG12;BWG10
Length	Up to 6 meters, custom cut lengths
Delivery Condition	Solution Annealed & Pickled; Bright Annealed
Ends	Plain End, Beveled End
Other Testing	Product Analysis, Eddy Current Test, Hydrostatic Test, Ultrasonic Test, Flattening Test, Hardness Test, Tensile Test etc.
Dimension	All Pipes & Tube Is Manufactured and Inspected / Tested to the Relevant standards including ASTM and ASME
Packing	Plywood case/Woven bag in bundle

 

ASTM A213 TP321 round tube Chemical Composition:

Grade	UNS	C	Mn	P	S	Si	Cr	Ni	Ti
TP321	S32100	0.08 max	2.00 max	0.045 max	0.03 max	1.00 max	17.0-19.0	9.0-12.0	5(C+N)-0.07
TP321H	S32109	0.04-0.10	2.00 max	0.045 max	0.03 max	1.00 max	17.0-19.0	9.0-12.0	4(C+N)-0.07

 

ASTM A213 TP321 seamless tube Mechanical Properties:

Grade	Tensile Strength, min, ksi (MPa)	Yield Strength, min, ksi (MPa)	Elongation in 2 in. or 50mm, min (%)	Hardness		Solutioning Temperature, min, °F(°C)
				Rockwell	Brinell/Vickers
TP321	75(515)	30(205)	35	90HRB	192HBW/200HV	1900(1040)
TP321H	75(515)	30(205)	35	90HRB	192HBW/200HV	2000(1090)

 

A213 SS Round Tube Heat Treatment

Heat Treatment Process	Description
Solution Annealing	1050°C to 1150°C
Annealing	1040°C and 1150°C
Quenching	1040°C to 1150°C
Stress Relieving	450°C to 650°C

 

SA 213 Stainless Steel Tube Tolerance

Outside Dia, milimeter	Outside Dia Tolerance
25.4 – <= 38.1	+/- 0.15
> 38.1 -< 50.8	+/- 0.20
< 25.4	+/- 0.10
76.2 – <= 101.6	+/- 0.38
> 101.6 – <= 190.5	+0.38/-0.64
50.8 -< 63.5	+/- 0.25
63.5 -< 76.2	+/- 0.30
> 190.5 – <= 228.6	+0.38/-1.14

 

A213 SS 321 high pressure tube Applications:

1.Food preparation equipment particularly in chloride environments.

2.Laboratory benches & equipment.

3.Coastal architectural panelling, railings & trim.

4.Boat fittings.

5.Chemical containers, including for transport.

6.Heat Exchangers.

7.Woven or welded screens for mining, quarrying & water filtration.

8.Threaded fasteners.

9.Springs.

 

Surface Condition

ASTM A213 ASME SA-213 TP321 Stainless steel tubes shall be pickled free of scale.
When bright annealing is used, pickling is not necessary.
Any special finish requirement shall be subject to agreement between the supplier and the purchaser.

 

We ensure product quality through 100% eddy current testing, hydrostatic testing, and the provision of Material Test Certificates (MTCs) complete with comprehensive chemical composition and mechanical property data. Leveraging over 15 years of export experience-with products sold to more than 60 countries worldwide-we offer rapid delivery, flexible Minimum Order Quantities (MOQs), and professional documentation services to fully meet the rigorous demands of sectors such as boilers, power plants, heat exchangers, and high-temperature chemical pipelines.

 

Packaging and Marking:

Packaging shall consist of bundles or plywood crates, wrapped in plastic, and shall incorporate appropriate protective measures to ensure seaworthy transport, or shall be carried out in accordance with specific requirements.
Marking shall comply with the provisions of Specification A1016/A1016M and shall indicate whether the tubing is hot-finished or cold-finished; markings shall include, but not be limited to: standard, grade, dimensions, heat number, and lot number.