ASME SA213 Seamless ferritic and austenitic alloy steel pipes for boilers, superheaters, and heat exchangers

1、 Standards and specifications

Applicable scenarios:

Specially designed for heat transfer pipelines that need to withstand high temperature and high pressure in boilers, superheaters, and heat exchangers, especially suitable for seamless steel pipes with minimum wall thickness design, with materials including ferritic and austenitic alloy steels.

Standard system:

ASME SA213 and ASTM A213 belong to the same standard system, and similar Chinese standards can refer to GB/T 14975-2002 (Seamless Stainless Steel Tubes for Structural Use).

2、 Material and Performance

Chemical composition

According to the differences in brand names, the typical composition range is as follows:

T11: C 0.05-0.15%, Cr 1.00-1.50%, Mo 0.44-0.65%;

T22: C ≤ 0.15%, Cr 1.90-2.60%, Mo 0.87-1.13%;

T91: C 0.08-0.12%, Cr 8.0-9.5%, Mo 0.85-1.05%.

Impurity control: P、S ≤0.035%， Improve high-temperature stability by 35.

Mechanical properties

Tensile strength: T11/T12/T22 ≥ 415MPa, T91 ≥ 585MPa;

Yield strength: T11 ≥ 170MPa, T12/T22 ≥ 205MPa, T91 ≥ 415MPa;

Elongation: T11/T22 ≥ 30%, T91 ≥ 20%.

3、 Manufacturing and Testing

Production process:

Adopting cold drawing/cold rolling forming (outer diameter 6-48mm, wall thickness 0.5-4mm) or hot rolling/forging (outer diameter 57-762mm, wall thickness 5-130mm), combined with heat treatment to optimize the grain structure.

Quality inspection:

Conduct hydrostatic testing and ultrasonic testing on each unit to ensure no leakage or internal defects;

Surface defects (cracks, folds) are strictly controlled according to standards.

4、 Application Fields

Power industry: boiler water-cooled wall, superheater pipeline (T91 is used in high-temperature steam environment);

Petrochemical/chemical plant: heat exchanger tube bundle, high-temperature oil and gas pipeline (T22/T91 has strong corrosion resistance);

Industrial boilers: high-pressure steam conveying systems and economizer pipelines.

5、 Selection suggestions

High temperature and high pressure environment: T91 (with a temperature resistance upper limit of 600 ℃) is preferred, as its high chromium molybdenum content enhances creep resistance;

Sulfur containing medium: Attention should be paid to the corrosion resistance of the material, and it is recommended to use austenitic stainless steel variants (such as SA213TP304H);

Thin walled requirements: Cold drawn process pipes (outer diameter tolerance ± 0.10mm) are suitable for compact heat exchanger layouts.