1. Key characteristics of F22 (EN 1.7380) valves:

F22 (EN 1.7380) is a low-alloy, heat-resistant chromium-molybdenum steel. This valve maintains its structural strength and creep resistance at temperatures up to 600°C, and exhibits extremely high resistance to hydrogen degradation and high-temperature hydrogen erosion within a temperature range of 500°C.

2. Key Advantages of Freeman Valve's F22 Valves:

2.1 Excellent High-Temperature Creep Performance of Freeman Valve's F22 Valves: 

F22 valves exhibit excellent allowable stress performance in the 450-540℃ range, making them a classic material for subcritical thermal power systems.

2.2 Good Resistance to Hydrogen Corrosion of Freeman Valve's F22 Valves: 

F22 valves demonstrate good resistance to high-temperature hydrogen-induced cracking (HIC) and hydrogen embrittlement, and are widely used in hydrogenation plants.

2.3 Strong Resistance to High-Temperature Sulfide Corrosion of Freeman Valve's F22 Valves: 

With a Cr content of 2.25%, F22 valves exhibit better resistance to H₂S sulfide corrosion than F11, but weaker than F5 (5Cr-0.5Mo).

3. Precautions for using F22 valves:

3.1 The operating temperature of F22 valves should not exceed 540℃: 

When the operating temperature of F22 valves exceeds 540℃, their creep strength rapidly decreases, therefore they cannot be used in supercritical units.

3.2 F22 valves have weaker sulfide resistance than F5 valves: 

In high-temperature, high-concentration H₂S media, the sulfide corrosion rate of F22 valves is higher than that of F5 valves, and strong corrosive media can cause oxidation-sulfide cross-corrosion.

3.3 F22 valves have limited oxidation resistance: 

When the operating temperature of F22 valves exceeds 550℃, the high-temperature oxidation rate increases significantly.

4. Key application areas of Freeman Valve's F22 valves:

4.1 Freeman Valve's F22 valves have been widely used in thermal power generation. For example: 

① Main steam pipelines of subcritical units;

② Subcritical boiler systems with steam temperatures ≤ 540℃;

4.2 Freeman Valve's F22 valves have been widely used in petroleum refining-hydrogenation units (hydrogen-containment conditions). For example: 

① Inlet and outlet of hydrogenation reactors, high-temperature hydrogen-containment pipelines;

② Hydrocracking, residue hydrogenation, high-temperature and high-pressure hydrogen environment;

4.3 Freeman Valve's F22 valves have been widely used in coal chemical and syngas plants. For example: 

High-temperature and high-pressure hydrogen-containing process pipelines;

4.4 Freeman Valve's F22 valves have been widely used in process steam systems. For example: 

High-temperature process steam systems with temperatures between 480-540℃;

5. F22 valves are not recommended for the following conditions:

① When the medium contains a high concentration of H₂S: F5 valves should be prioritized, and F22 valves are not recommended;

② When the medium has strong sulfide corrosion: F5 valves should be prioritized, and F22 valves are not recommended;

③ When the temperature is >540℃: F91 valves should be prioritized.