Application and production process of A335 P11 seamless alloy pipe

Application of A335 P11 seamless alloy pipe:

A335 P11 seamless alloy pipe is a seamless ferritic alloy steel pipe for high temperature, which meets the ASTM A335/A335M standard. P11 seamless alloy steel pipe is made of high-quality carbon alloy steel, with excellent high temperature resistance, high pressure resistance and corrosion resistance, and is widely used in many industrial fields. This alloy pipe is mainly used in power, petroleum, chemical industry, nuclear industry, aerospace and boiler fields, especially in high temperature and high pressure environment.

1. Power industry
Core components: boiler pipes, superheaters, reheaters, economizers of thermal power plants.
Performance requirements: withstand high temperature (up to 600℃) and high pressure (working pressure above 9.8MPa) to ensure the safety and stability of the power generation process.

2. Petrochemical industry
Application scenarios: high temperature and high pressure pipeline systems, heat exchangers, reactors, distillation units.
Media adaptation: transport media containing corrosive components (such as hydrogen sulfide, high temperature oil and gas), with strong corrosion resistance.

3. Nuclear industry
Key uses: cooling systems and high-pressure pipelines in nuclear power plants.
Safety features: excellent high temperature resistance and radiation resistance to ensure long-term stable operation of nuclear power plants.

4. Aerospace
High temperature components: combustion chambers of aircraft engines, turbine blades, etc.
Material advantages: lightweight design combined with high temperature strength to improve engine efficiency.

5. Other fields
Valves and flanges: manufacture pipeline accessories under high temperature and high pressure to ensure sealing and corrosion resistance.
Hot processing equipment: such as rollers and heating furnace components in steel mills.

Production process of A335 P11 seamless alloy pipe:

The production process of A335 P11 seamless alloy pipe strictly follows ASTM standards to ensure that the material has excellent mechanical properties and corrosion resistance. Key process steps include:

1. Smelting and refining

Dual process: LF refining furnace + VD vacuum degassing is used to control the hydrogen content ≤2ppm and reduce impurities.
Continuous casting billet quality: surface finish Ra≤12.5μm, grain size reaches ASTM 8 level, ensuring subsequent processing performance.

2. Forming processing

Hot rolling process:
Temperature control: 1200℃ high temperature piercing and continuous rolling, precise control of outer diameter (21.3-760mm).
Dimensional accuracy: through the sizing process, ensure that the outer diameter and wall thickness meet the standards.

Cold drawing process:
Multi-pass diameter reduction: control the wall thickness tolerance ±0.5mm during the stretching process to improve the material density.

3. Heat treatment strengthening

Normalizing + tempering:
Normalizing temperature: 900-950℃, homogenize the structure and eliminate internal stress.
Tempering temperature: 680-720℃, improve toughness, final hardness HB≤163, impact energy longitudinal ≥40J.

4. Cutting technology

Flame cutting: applicable to wall thickness ≥20mm, heat affected zone needs to be polished after cutting to prevent hydrogen cracking.
Plasma cutting: accuracy ±1mm, efficiency is 3 times faster than flame cutting, and the cut has its own oxide layer cleaning function.

Mechanical cutting: Band saw cutting has no thermal deformation, and the roughness of the grinding wheel is ≤3.2μm after fine-tuning, which meets the requirements of high-pressure sealing.

Performance advantages of A335 P11 seamless alloy pipe:

Chemical composition: contains chromium (Cr) 1.00%-1.50%, molybdenum (Mo) 0.46%-0.65%, enhancing oxidation resistance and high temperature strength.
Mechanical properties: tensile strength ≥415MPa, yield strength ≥205MPa, elongation ≥30%.
Process performance: excellent weldability and processability, suitable for complex component manufacturing.

Inspection standards:
Quality certification: in accordance with TSG D7002 pressure pipeline component type test rules.
Seamless alloy pipe non-destructive testing: ultrasonic, eddy current and other tests are required to ensure that there are no internal defects.
Water pressure testing.

Read more: ASTM A335 P11 vs P22 or ASME SA335 P91 VS SA335 P22