ASTM A335 P22 Alloy Steel Seamless Tube With 11-13CR HFW Fin Tube For Convection Coil

ASTM A335 P22 Alloy Steel Seamless Tube With 11-13CR, HFW Fin Tube, For Convection Coil

1. Product Overview

The ASTM A335 P22 Alloy Steel Seamless Tube with 11-13% Chromium (Cr) HFW Fin Tube is engineered for high-efficiency heat transfer in extreme temperature and pressure environments. Combining the high-temperature strength of P22 alloy steel with the corrosion resistance of chromium-rich fins, this product is ideal for convection coils in boilers, heaters, and industrial thermal systems.

2. Material Standards & Chemical Composition

Base Tube: ASTM A335 P22 Alloy Steel

Fin Strip: 11-13% Chromium Steel

3. Mechanical Properties

4. Key Advantages

1. High-Temperature Durability

   • P22 alloy steel withstands temperatures up to 650°C with superior creep resistance, ideal for superheaters and reformers.

   • Chromium fins resist oxidation in flue gas and acidic environments.

2. Corrosion & Sulfidation Resistance

   • 11-13Cr fins prevent sulfidation cracking in sulfur-rich atmospheres (e.g., refinery heaters).

3. Optimized Heat Transfer

   • HFW fins increase heat exchange surface area by 4–6x, enhancing efficiency while maintaining low pressure drop.

4. Robust Welding Quality

   • High-frequency welding ensures fin-to-tube bond strength ≥85% of base metal, validated by shear testing.

5. Cost-Effective Solution

   • Combines the high-temperature performance of P22 with the corrosion resistance of Cr steel, reducing downtime and maintenance costs.

5. Manufacturing & Quality Control

1. Base Tube Production

   • Seamless manufacturing via hot extrusion or rotary piercing, compliant with ASTM A335.

   • Heat treatment: Normalized at 900–940°C, tempered at 690–730°C for optimal microstructure.

2. Fin Welding Process

   • HFW fin attachment: Welding speed 8–25 m/min, frequency 200–450 kHz.

   • Post-weld stress relief (PWHT) at 600–650°C to eliminate residual stresses.

3. Testing & Certification

   • Non-Destructive Testing (NDT): 100% UT/RT on base tube; PT/MT on welds.

   • Hydrostatic Testing: 1.5x design pressure (ASME B31.1 compliant).

   • Certificates: ASME Section II, EN 10204 3.1, and PED 2014/68/EU.

6. Applications

7. Comparison with Alternatives