ASTM A249 Welded Austenitic Stainless Steel Tube For Heat Exchanger Boiler Service

ASTM A249 / A249M is a standard specification issued by ASTM International for welded austenitic stainless steel tubes used in boilers, superheaters, heat exchangers, condensers, and hydraulic systems. These tubes are manufactured using GTAW or ERW processes and are supplied in the solution annealed condition to ensure corrosion resistance and high-temperature strength.

This product covers common grades such as TP304, TP304L, and TP304H, making it particularly suitable for high-temperature, high-pressure applications in heat exchangers and boiler tube bundles.

Grade Notes:

• “H" grades (TP304H / TP316H / TP321H / TP347H) are specifically designed for high-temperature service (e.g., superheaters and reheaters), offering improved creep rupture strength.

• “L" grades (TP304L) have lower carbon content, providing better resistance to intergranular corrosion after welding.

Heat Treatment Requirement: Tubes shall be supplied in the solution annealed condition, typically heated to a minimum of 1900°F (1040°C) followed by rapid cooling.

All tubes are tested in accordance with ASTM A1016/A1016M general requirements, including:

• Chemical analysis (per heat)

• Tensile test

• Flattening test

• Flaring test

• Reverse flattening test (if applicable)

• Non-Destructive Testing:

  • 100% Eddy Current Test (ET)

  • or 100% Hydrostatic Test

  • Optional: Radiography (RT) for critical welds

Certificates Available:

• Manufacturer’s Test Certificate (EN 10204 3.1)

• Third-party inspection report (SGS, BV, TUV – upon request)

• Heat treatment records

• 100% Radiography Test Report (if applicable)

• DFARS compliance statement (if required)

• Packaging: PE fabric bundles, plywood wooden cases, or standard seaworthy export packing

• Protection: Plastic caps on ends (if applicable), moisture-proof lining inside

• Marking: Grade, size, heat number, standard clearly labeled

• Port of Loading: As agreed (e.g., Qingdao, Shanghai – major ports)

The following requirements should be specified by the purchaser at the time of ordering:

1. Quantity (feet, meters, or number of lengths)

2. Name of material – Welded tubes (WLD) or Heavily Cold Worked tubes (HCW)

3. Grade (per Standard Table 1)

4. Size (outside diameter and nominal wall thickness)

5. Length (specific or random)

6. Optional requirements (e.g., special finish, testing)

7. Test report required

8. Specification designation (ASTM A249/A249M)

9. Special requirements and supplementary requirements (if any)

1. What is the difference between ASTM A249, A269, and A213?

2. How does TP304H differ from TP304 in high-temperature performance?
TP304H has a controlled carbon content of 0.04–0.10% (higher than ≤0.08% for standard TP304) and undergoes specific heat treatment, resulting in improved creep rupture strength for continuous service above 550°C.

3. Can welded tubes be used in high-pressure heat exchangers?
Yes. Provided they meet the standard’s requirements for 100% Eddy Current or Radiographic testing, and pass flattening/flaring tests, welded tubes are widely used in heat exchangers and condensers with design pressures exceeding 10 MPa.

4. What is the minimum order quantity?
It depends on size and wall thickness. Small-diameter, thin-wall tubes for heat exchangers (e.g., 19.05*1.65mm) typically have lower MOQs. Please provide your specific requirements for evaluation.

5. Can you provide a 3.2 certificate?
Yes, but this usually involves additional cost and may require witnessed testing. Please specify the need for an EN 10204 3.2 certificate, and we will arrange for an accredited third-party to perform the required tests.

6. What internal surface roughness can be achieved for polished tubes?
Mechanical polishing can achieve Ra ≤ 0.4 µm; electropolishing can achieve Ra ≤ 0.2 µm, suitable for high-purity media and pharmaceutical-grade applications.