In the power industry, valves play a crucial role in power plants and transmission/distribution systems. They are used to control and regulate the flow of various media including water, steam, coolant, fuel, etc., ensuring efficient, safe, and stable operation of power generation processes. Due to the special requirements of the power industry, valves need to possess high-pressure, high-temperature, and high-sealing capabilities. Below are specific applications and special requirements of valves in the power industry:
Application Scenarios
1. Boiler Systems:
- Control the flow and pressure of water and steam in boilers.
- Valves need to withstand high temperatures, high pressures, and corrosion.
2. Turbine Systems:
- Regulate the flow and pressure of steam entering turbines.
- Require high-precision control and high-temperature resistance.
3. Cooling Systems:
- Control the flow of cooling water and coolant to maintain equipment temperature.
- Require corrosion resistance and reliability.
4.Fuel Supply Systems:
- Control the supply and flow of fuel to ensure combustion efficiency.
- Need high sealing and corrosion resistance.
1. Feedwater Systems:
- Regulate the flow and pressure of boiler feedwater.
- Require valves with high-pressure and high-temperature resistance.
6. Desulfurization and Denitrification Systems:**
- Control the flow of chemical agents during flue gas treatment and emission of reaction products.
- Require valves with corrosion resistance and wear resistance.
Special Requirements
1. High-Temperature and High-Pressure Resistance:
- Boilers and turbine systems in power plants often operate under high temperatures and pressures.
- Valve materials must withstand these harsh conditions, commonly using alloy steel, stainless steel, etc.
2. High Sealing Performance:
- Ensure no leakage under high-temperature and high-pressure conditions to prevent medium wastage and system damage.
- Use high-quality sealing materials such as metal seals or composite sealing materials.
3. Corrosion Resistance:
- Valves handling cooling water, fuel, and chemical agents need to resist corrosion.
- Use corrosion-resistant materials such as stainless steel, Hastelloy alloys, or fluoropolymer lining materials.
4. Wear Resistance:
- Valves in desulfurization and fuel supply systems need to be wear-resistant.
- Use materials like hard alloys or ceramic coatings.
2. High-Precision Control:
- Require precise control of steam and fuel flow to ensure efficient system operation.
- Use high-precision control valves and control systems.
Typical Valve Types
1. Gate Valves:
- Suitable for fluid shut-off and flow control.
- Strong structure, high-temperature and high-pressure resistant, suitable for boilers and feedwater systems.
2. Ball Valves:
- Suitable for quick opening/closing and tight shut-off applications.
- Full-bore design reduces fluid resistance, suitable for fuel supply and cooling systems.
3. Butterfly Valves:
- Suitable for flow control in large-diameter pipelines.
- Simple structure, lightweight, quick operation, suitable for cooling and desulfurization systems.
4. Globe Valves:
- Suitable for applications requiring precise flow control.
- Simple structure, superior regulation performance, suitable for boilers and turbine systems.
5. Check Valves:
- Prevent reverse flow to protect equipment safety.
- Suitable for various process pipeline systems.
6. Safety Valves:
- Prevent system overpressure, ensuring equipment and personnel safety.
- Suitable for boiler and pressure vessel systems.
7. Pressure Reducing Valves:
- Used in water and steam systems to ensure constant outlet pressure.
- High-precision adjustment, rapid response, suitable for boiler feedwater and steam systems.
Maintenance and Operation Considerations
1. Regular Inspection and Maintenance:
- Regularly inspect valve sealing and operational performance, promptly replace worn or damaged parts.
- Clean valves internally and externally to prevent fouling and corrosion.
2. Lubrication:
- Regularly apply suitable lubricants to valves requiring lubrication to ensure smooth operation.
- Use lubricants suitable for high-temperature and high-pressure environments to prevent lubricant failure.
3. Fastening Component Inspection:
- Regularly check fastening components of valve connections to ensure tightness and prevent leaks.
4. Operating Procedures:
- Operators must strictly adhere to operating procedures to avoid excessive force or rapid operation.
- Provide operational training to ensure operators understand valve performance and operating methods.
5. Emergency Response:
- Develop and familiarize personnel with emergency response plans to promptly address emergencies such as valve leaks or failures.
Typical Cases
1. Gate Valves for Boiler Systems:
- Gate valves used in boiler systems require high-temperature and high-pressure performance; valve bodies and gates are typically made of alloy steel or high-temperature alloy materials.
2. Control Valves for Turbine Systems:
- Control valves used in turbine systems require high-precision control and high-temperature resistance; valve bodies and cores are made of stainless steel or titanium alloy materials.
3.Ball Valves for Cooling Systems:
- Ball valves used in cooling systems require high sealing and corrosion resistance; valve bodies and balls are made of stainless steel or bronze materials.
4. Butterfly Valves for Fuel Supply Systems:
- Butterfly valves used in fuel supply systems require corrosion resistance and high sealing performance; valve bodies and discs are made of Hastelloy alloys or fluoropolymer lining materials.
5. Check Valves for Desulfurization Systems:
- Check valves used in desulfurization systems require wear resistance and corrosion resistance; valve bodies and discs are made of hard alloys or ceramic coatings.
By selecting appropriate valve types and materials, and conducting regular maintenance and inspections, valves in the power industry can operate stably in various demanding environments, thereby enhancing power production efficiency and system safety.