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| Brand Name: | YUHONG |
| Model Number: | ASTM A213 TP304L Stainless Steel U Bend Tube |
| MOQ: | 1000kgs |
| Payment Terms: | L/C,T/T |
ASTM A213 / ASME SA213 TP304L / 1.4307 Stainless Steel Seamless Tube U Bend Heat Exchanger Tube
ASTM A213 TP304L Stainless Steel U Bend tubes are the workhorse of the food, dairy, and light chemical industries. Their success lies not in high strength or exotic corrosion resistance, but in predictable forming behavior and reliable weldability. When procuring these, the highest risks are residual stress and surface contamination. When specified correctly, inspected thoroughly, and installed in appropriate environments, it delivers decades of maintenance-free service at a fraction of the cost of high-alloy alternatives.
| Grade | UNS No | Old British | Euronorm | Swedish SS | Japanese JIS | ||
| BS | En | No | Name | ||||
| 304L | S30403 | 304S11 | - | 1.4306 | X2CrNi19-11 | 2352 | SUS 304L |
ASTM A213 TP304L Stainless Steel U Bend Tube Chemical Composition
| Grade | C | Mn | Si | P | S | Cr | Mo | Ni | N | |
| 304L | min. | - | - | - | - | - | 18.0 | - | 8.0 | - |
| max. | 0.030 | 2.0 | 0.75 | 0.045 | 0.030 | 20.0 | 12.0 | 0.10 | ||
ASTM A213 TP304L Stainless Steel U Bend Tube Mechanical Properties
| Grade |
Tensile Strength (MPa) min |
Yield Strength 0.2% Proof (MPa) min |
Elongation (% in 50mm) min |
Hardness | |
| Rockwell B (HR B) max | Brinell (HB) max | ||||
| 304L | 485 | 170 | 40 | 92 | 201 |
Special Test for Stainless Steel/Duplex Steel Tubing
1. Stress Corrosion Cracking (SCC) at the Apex
Scenario: 304L U-bends in hot water (>140°F) with trace chlorides.
Mechanism: The outer radius has high residual tensile stress from bending. Chlorides attack the stressed grain boundaries.
Mitigation: If the water chemistry cannot be controlled, specify solution annealing after bending to relieve stress, or upgrade to 316L or Duplex 2205.
2. IGA (Intergranular Attack)
Scenario: Improper hot bending.
Mechanism: If the tube is heated to 900-1500°F and the carbon content is at the high end of the spec (0.035%) or if it is misgraded 304, chromium carbides precipitate. The area adjacent to the weld (heat affected zone) becomes "sensitized."
Solution: Verify the material certs (MTR) show low carbon; perform a Strauss Test (A262 Practice E) if required.
3. Erosion-Corrosion
Location: Inner radius of the U-bend.
Cause: Turbulent flow scouring the passive layer.
Note: 304L relies on a chromium oxide layer. If the media is erosive (slurries), the passive layer is stripped away faster than it can re-form.
Application
