ASME SA213 TP321 Stainless Steel U Bend Tube for Heat Exchanger

​​GNEE provides ASME SA213 TP321 stainless steel U-bend tubes​​, manufactured from ​​321 stainless steel​​ and formed through ​​precision bending processes​​, followed by ​​solution annealing + pickling and passivation treatments​​ to achieve a ​​stable austenitic structure​​. These tubes ​​withstand continuous 900°C high temperatures and short-term exposure up to 1100°C​​.

 

Strictly adhering to the ​​ASME SA213 standard​​, the tubes feature ​​outer diameter tolerances of ±0.10 mm and wall thickness tolerances of ±10%​​, with ​​multiple specifications available (e.g., outer diameters of 12.7-114.3 mm, wall thicknesses of 0.89-6.35 mm) and customization services​​. They offer a ​​high surface finish (roughness Ra ≤ 0.8 μm)​​ and ​​smooth, oxidation-free inner walls​​, ensuring ​​low fluid resistance and high heat transfer efficiency​​.

 

The ​​TP321 stainless steel U-bend tubes​​ undergo ​​multiple validations​​, including ​​eddy current testing (ET), hydrostatic testing (≥20 MPa), and intergranular corrosion testing (per ASTM G28 standard)​​, guaranteeing ​​zero leakage risk and long service life​​. They are specifically designed for ​​high-temperature, high-pressure heat exchangers, boiler superheaters/reheaters​​, and other applications with demanding requirements for ​​temperature resistance, corrosion resistance, and mechanical performance​​.

 

 

Equivalent Grade of ASTM A213 TP321/TP321 Stainless Steel Seamless Tubing

Grade	UNS No	Old British		Euronorm		Swedish SS	Japanese JIS
		BS	En	No	Name
321	S32100	321S31	58B, 58C	1.4541	X6CrNiTi18-10	2337	SUS 321
321H	S32109	321S51	-	1.4878	X10CrNiTi18-10	-	SUS 321H

Chemical Composition of ASTM A213 TP321/TP321 Stainless Steel Seamless Tubing

	SS 321	SS 321H
Ni	9 – 12	9 – 12
Cr	17 – 19	17 – 19
C	0.08 max	0.04 – 0.10
N	0.10 max
Fe	Balance
Mn	2 max	2 max
Si	0.75 max	0.75 max
S	0.03 max	0.03 max
P	0.045 max	0.045 max
Ti	5xC min 0.60% max	4xC min 0.60% max

 

Mechanical & Physical Properties of ASTM A213 TP321/TP321 Stainless Steel Seamless Tubing

Density	8.0 g/cm3
Melting Point	1454 °C (2650 °F)
Tensile Strength	Psi – 75000 , MPa – 515
Yield Strength (0.2%Offset)	Psi – 30000 , MPa – 205
Elongation	35 %

 

Application

1. Power Generation (Fossil Fuel & Biomass)

2. Petrochemical & Refining

3. Chemical Processing Industry

4. Oil & Gas (Upstream & Midstream)

5. Other Industrial Applications

 

What is the difference between 304, 304L and 304H stainless steel heat exchanger tube?

1.There are hundreds of different grades of stainless steel on the market. Each of these unique stainless steel formulations offers a degree of corrosion resistance superior to that of ordinary steel.

2.The presence of these stainless steel variants can cause some confusion - especially when the names and formulations of the two stainless steel alloys are nearly identical. This is the case with 304 and 304L stainless steel.

 

GNEE Stainless Steel is a specialized manufacturer of Stainless Steel U Bend Tube / Stainless Steel U bent Tubes for U Tube Heat Exchanger (U bent Stainless Steel Tube for U bent Tube Heat Exchanger). Our U Bend Tube Tube-bending production line, installed in 2008. Solution annealing after bending will be processed to lower the residual stress, and followed by Hydrostatic testing/Pneumatic test and Dye Penetrant testing if required.

Fully compliant with ASTM A213/ASME SA213 standards, with options for mill test certificates (EN 10204 3.1) and third-party inspection reports to ensure traceability and adherence to international quality requirements. Email: sales@gneestainless.com

 

Packaging and Marking:
Packaged in bales or laminated wooden crates, wrapped in plastic, and appropriately protected to ensure seaworthiness for transport, or as required.
Marking must comply with Specification A1016/A1016M. Marking must include information on whether the pipe is hot-finished or cold-finished, including but not limited to: standard, grade, size, heat number, and batch number.