Ventil motýlů: Jak to funguje, Typy, and Key Benefits

4. Key Components and Materials

Major Components of a Butterfly Valve

Tělo ventilu

• • Funkce: The valve body is the main housing that contains all the other components.
    It provides structural integrity and ensures that the valve can withstand the pressure and temperature of the fluid passing through it.
  • Design: Obvykle, the body is designed to fit between two flanges or can be installed in a wafer configuration.

Disk

• • Funkce: The disc is the circular plate that controls the flow of fluid. It rotates around a central axis to open or close the valve.
  • Design: The disc can be either concentric or offset, depending on the type of butterfly valve (NAPŘ., double offset or triple offset).

Sedadlo

• • Funkce: The seat is the sealing surface that ensures a tight closure when the valve is in the closed position. It forms a seal around the disc to prevent any leakage.
  • Design: Seats can be made of various materials and can be either resilient (měkký) or metal-to-metal, depending on the application requirements.

Zastavit

• • Funkce: The stem connects the disc to the actuator and allows for the rotation of the disc. It transmits the torque from the actuator to the disc.
  • Design: The stem can be one-piece or multi-piece, and it can be either solid or hollow, depending on the valve design and application.

Těsnění

• • Funkce: Seals prevent leaks around the stem and other moving parts, ensuring that the valve operates efficiently and safely.
  • Design: Seals can be made of various materials, such as O-rings, těsnění, and packing, and are often designed to be easily replaceable.

Common Materials Used in Butterfly Valves

Body Materials

• • Nerez: Corrosion-resistant and durable, aby bylo vhodné pro širokou škálu aplikací, including chemical and petrochemical processes.
    Such us: CF8, CF3, CF8M, CF3M.
  • Uhlíková ocel: Silné a nákladově efektivní, commonly used in high-pressure and high-temperature applications.
  • Tažné železo: Economical and durable, often used in water and wastewater treatment systems.
  • Plast: Lightweight and resistant to certain chemicals, suitable for low-pressure and low-temperature applications.

Disc Materials

• • Nerez: Corrosion-resistant and durable, ideal for applications involving corrosive media. Such us: CF8, CF3, CF8M, CF3M.
  • Hliník: Lehký a odolný proti korozi, suitable for low-pressure and low-temperature applications.
  • Various Alloys: Special alloys can be used for specific applications, such as high-temperature or high-corrosion environments.

Seat Materials

• • PTFE (Polytetrafluorethylen): Chemically inert and has excellent non-stick properties, making it suitable for a wide range of fluids.
  • EPDM (Monomer ethylen propylen dienu): Resistant to a wide range of chemicals and temperatures, commonly used in water and wastewater applications.
  • NBR (Nitrile Butadiene Rubber): Resistant to oils and fuels, suitable for petrochemical applications.
  • Other Elastomers: Various other elastomers can be used depending on the specific requirements of the application.

Stem Materials

• • Nerez: Corrosion-resistant and strong, aby bylo vhodné pro širokou škálu aplikací.
  • Uhlíková ocel: Silné a nákladově efektivní, commonly used in high-pressure and high-temperature applications.

Material Selection Considerations

• Odolnost proti korozi: Choose materials that can withstand the corrosive nature of the fluid being controlled.
• Teplota a tlak: Select materials that can handle the operating temperature and pressure of the system.
• Chemická kompatibilita: Ensure that the materials are compatible with the specific chemicals or fluids in the system.
• Náklady a dostupnost: Consider the cost and availability of materials, balancing performance requirements with budget constraints.

By carefully selecting the appropriate materials for each component, you can ensure that the butterfly valve performs reliably and efficiently in its intended application.

This attention to detail in material selection is crucial for maintaining the longevity and effectiveness of the valve.

5. Typy klapkových ventilů

Butterfly valves come in various types, each designed to meet specific application requirements.

Understanding the differences between these types can help you choose the right valve for your needs. Here’s a detailed look at the main types of butterfly valves:

Lug Butterfly Valve

Popis: A lug butterfly valve features threaded inserts or lugs on the outside of the valve body.

These lugs allow the valve to be installed between two flanges and can be used in dead-end service.

Typické aplikace:

• Voda a čištění odpadních vod: Ideal for controlling the flow of water and wastewater in treatment plants.
• Chemické zpracování: Suitable for applications involving corrosive chemicals.

Výhody:

• Dead-End Service: This can be used in dead-end service, where one side of the valve can be isolated.
• Ease of Removal: Easy to remove for maintenance or replacement.

Nevýhody:

• Náklady: Generally more expensive than wafer valves.
• Hmotnost: Heavier than wafer valves, which can affect installation and handling.

Data Points:

• Lug butterfly valves can handle pressures up to 600 psi and temperatures ranging from -40°F to 450°F.
• They are available in sizes from 2 inches to 72 palce.

Ventil motýlů

Popis: A wafer butterfly valve is sandwiched between two flanges and held in place by bolts. It does not have external lugs and relies on the flanges for support.

Typické aplikace:

• HVAC systémy: Commonly used in heating, větrání, and air conditioning systems to regulate air and water flow.
• Systémy požární ochrany: Used in fire sprinkler systems to control water flow.

Výhody:

• Lightweight and Cost-Effective: Lighter and less expensive than lug valves.
• Compact Design: This takes up less space, making it ideal for installations with limited space.

Nevýhody:

• Not Suitable for Dead-End Service: Cannot be used in dead-end service, as it cannot isolate one side of the valve.
• Alignment: Requires proper alignment during installation to ensure a secure fit.

Data Points:

• Wafer butterfly valves can handle pressures up to 300 psi and temperatures ranging from -40°F to 250°F.
• They are available in sizes from 2 inches to 72 palce.

Double Offset Butterfly Valve (D0)

Popis: The double-offset butterfly valve has the stem offset from the centerline of the disc and the body. This design reduces wear and improves sealing performance.

Typické aplikace:

• Petrochemical and Chemical Industries: Used in high-performance applications where precise flow control and minimal wear are critical.
• Farmaceutický průmysl: Suitable for applications requiring high purity and minimal contamination.

Výhody:

• Better Sealing: Improved sealing performance due to the offset design.
• Reduced Wear: Less wear on the disc and seat, extending the valve’s lifespan.

Nevýhody:

• Složitost: More complex design compared to standard butterfly valves, which can increase cost.
• Higher Cost: Generally more expensive than standard butterfly valves.

Data Points:

• Double offset butterfly valves can handle pressures up to 1,000 psi and temperatures ranging from -40°F to 600°F.
• They are available in sizes from 2 inches to 60 palce.

Trojitý přesazený motýlový ventil (T0)

Popis: The triple offset butterfly valve features three offsets, providing a metal-to-metal seal and zero leakage.

The design ensures a tight seal even under high-pressure and high-temperature conditions.

Typické aplikace:

• High-Temperature and High-Pressure Systems: Ideal for power generation plants and other systems with extreme operating conditions.
• Kryogenní aplikace: Suitable for systems involving very low temperatures, such as LNG storage and transportation.

Výhody:

• Zero Leakage: Provides a metal-to-metal seal, ensuring zero leakage.
• High-Pressure Capability: Capable of handling high pressures and temperatures.

Nevýhody:

• Most Expensive: The most expensive type of butterfly valve due to its complex design and high-performance materials.
• Complex Design: More complex and requires specialized maintenance.

Data Points:

• Triple offset butterfly valves can handle pressures up to 1,500 psi and temperatures ranging from -320°F to 1,200°F.
• They are available in sizes from 2 inches to 48 palce.

Vysoce výkonný motýlový ventil (HPBV)

Popis: High-performance butterfly valves are designed to offer superior sealing and flow control capabilities.

They often feature advanced materials and designs to handle demanding applications.

Typické aplikace:

• Ropný a plynárenský průmysl: Used in pipelines and processing facilities to control the flow of hydrocarbons.
• Chemické zpracování: Suitable for applications involving aggressive chemicals and high temperatures.

Výhody:

• Superior Sealing: Enhanced sealing performance for critical applications.
• Trvanlivost: Built to withstand harsh operating conditions and extended use.

Nevýhody:

• Náklady: More expensive than standard butterfly valves.
• Údržba: Requires regular maintenance to ensure optimal performance.

Data Points:

• High-performance butterfly valves can handle pressures up to 1,200 psi and temperatures ranging from -40°F to 800°F.
• They are available in sizes from 2 inches to 60 palce.

Eccentric Butterfly Valve

Popis: An eccentric butterfly valve has an offset disc that helps reduce wear and improve sealing.

The eccentric design allows the disc to lift away from the seat when opening, reducing friction and wear.

Typické aplikace:

• Slurry Applications: Ideal for handling slurries and other abrasive media.
• Úpravy vody: Used in water treatment plants to control the flow of water and wastewater.

Výhody:

• Reduced Wear: The eccentric design reduces wear on the disc and seat.
• Improved Sealing: Better sealing performance, especially in slurry applications.

Nevýhody:

• Složitost: More complex design compared to standard butterfly valves.
• Náklady: Generally more expensive than standard butterfly valves.

Data Points:

• Eccentric butterfly valves can handle pressures up to 600 psi and temperatures ranging from -40°F to 450°F.
• They are available in sizes from 2 inches to 72 palce.

6. Butterfly Valve Actuation

Butterfly valves can be actuated in several ways to control the flow of fluids.

The choice of actuation method depends on the specific application requirements, such as the frequency of operation, the need for precise control, and the operating environment.

Here are the main types of butterfly valve actuation:

Manual Actuation

Popis: Manual actuation involves using a handwheel or lever to rotate the valve stem and disc. This is the simplest and most cost-effective method of actuation.

Typické aplikace:

• Low-Frequency Operations: Suitable for applications where the valve is rarely opened or closed, such as in small industrial plants or residential settings.
• Emergency Shut-Off: Often used for emergency shut-off valves where quick manual intervention is necessary.

Data Points:

• Manual butterfly valves can handle pressures up to 600 psi and temperatures ranging from -40°F to 450°F.
• They are available in sizes from 2 inches to 72 palce.

Pneumatic Actuation

Popis: Pneumatic actuation uses compressed air to move the valve stem and disc. Pneumatic actuators are reliable and can provide fast and precise control.

Typické aplikace:

• Řízení procesů: Commonly used in process control systems where rapid and accurate flow control is essential.
• Automated Systems: Suitable for fully automated systems in industries like petrochemicals and pharmaceuticals.

Data Points:

• Pneumatic butterfly valves can handle pressures up to 1,000 psi and temperatures ranging from -40°F to 450°F.
• They are available in sizes from 2 inches to 60 palce.

Electric Actuation

Popis: Electric actuation uses an electric motor to rotate the valve stem and disc. Electric actuators are versatile and can be programmed for precise control.

Typické aplikace:

• Remote Locations: Ideal for remote or hard-to-reach locations where pneumatic or hydraulic systems may not be feasible.
• Automatizace: Suitable for fully automated systems in industries like oil and gas, úpravy vody, and HVAC.

Data Points:

• Electric butterfly valves can handle pressures up to 1,200 psi and temperatures ranging from -40°F to 450°F.
• They are available in sizes from 2 inches to 60 palce.

Hydraulic Actuation

Popis: Hydraulic actuation uses pressurized fluid to move the valve stem and disc. Hydraulic actuators are powerful and can handle high torque requirements.

Typické aplikace:

• Heavy-Duty Applications: Suitable for heavy-duty applications in industries like mining, výroba energie, and shipbuilding.
• High Torque Requirements: Ideal for large valves that require significant torque to operate.

Data Points:

• Hydraulic butterfly valves can handle pressures up to 1,500 psi and temperatures ranging from -40°F to 450°F.
• They are available in sizes from 2 inches to 72 palce.

Solenoid Actuation

Popis: Solenoid actuation uses an electromagnetic coil to move a plunger, which in turn moves the valve stem and disc. Solenoid actuators are compact and provide quick on/off control.

Typické aplikace:

• On/Off Control: Ideal for applications requiring simple on/off control, such as in irrigation systems and small industrial processes.
• Emergency Shut-Off: Often used for emergency shut-off valves where quick response is critical.

Data Points:

• Solenoid butterfly valves can handle pressures up to 300 psi and temperatures ranging from -40°F to 250°F.
• They are available in sizes from 2 inches to 12 palce.

7. Výhody klapkových ventilů

Butterfly valves offer significant benefits across various applications, včetně:

• Lightweight and Compact: They require less space, making them suitable for compact systems or limited-space installations.
• Quick Operation: With a quarter-turn design, butterfly valves allow for rapid open/close cycles, essential in time-sensitive processes.
• Cost-Efficiency: Compared to more complex valve types, butterfly valves are simpler and more economical to produce.
• Všestrannost: Butterfly valves accommodate a variety of media, including liquids, plyny, and even semi-solid slurries.

8. Limitations of Butterfly Valves

• Potential Leakage in Higher-Pressure Applications: While they excel in low-pressure applications, butterfly valves may not be suitable for extremely high-pressure systems, where they might experience leaks.
• Less Precise Flow Control: They do not offer the same level of precision as globe valves for fine flow control.
• Wear and Tear in High-Stress Environments: In harsh conditions, the components of butterfly valves can wear out more quickly, requiring regular inspection and maintenance.

9. Aplikace klapkových ventilů

Průmyslové aplikace:

• Voda a čištění odpadních vod: Butterfly valves are widely used in water treatment plants to manage the flow of water and wastewater, ensuring efficient and reliable operation.
• Petrochemické a chemické zpracování: They control the flow of chemicals and petrochemicals in various processing units, maintaining safety and efficiency.
• HVAC systémy: Butterfly valves regulate air and water flow in heating, větrání, and air conditioning systems, optimizing energy use and comfort.
• Průmysl potravin a nápojů: They control the flow of liquids and gases in food processing, ensuring hygiene and compliance with industry standards.

Residential and Commercial Applications:

• Plumbing Systems: Butterfly valves manage water flow in residential and commercial plumbing systems, ensuring consistent water supply.
• Systémy požární ochrany: They control the flow of water in fire sprinkler systems, enhancing fire safety.

Specialized Applications:

• High-Temperature and High-Pressure Systems: Butterfly valves are used in systems with extreme conditions, such as power generation plants.
• Kryogenní aplikace: They are employed in systems involving very low temperatures, such as LNG storage and transportation.

10. Comparison with Other Valves

• Brány ventily: Gate valves are used for on/off control and are better suited for high-pressure applications.
  Klapkové ventily, však, are more compact and cost-effective, making them ideal for large-scale systems.
• Kulové ventily: Ball valves offer excellent shut-off capabilities but have a higher pressure drop.
  Klapkové ventily, na druhé straně, are more suitable for high-flow, low-pressure applications due to their lower pressure drop.
• Globe ventily: Globe valves provide precise flow control but are more expensive and have a higher pressure drop.
  Butterfly valves are more cost-effective and easier to install, making them a preferred choice for many applications.

11. Butterfly Valve Selection Tips

• Considerations for Choosing the Right Valve Type, Materiál, and Size:

• • Flow Rate: Ensure the valve can handle the required flow rate, typically measured in gallons per minute (GPM) or cubic meters per hour (m³/h).
  • Tlak: Select a valve that can withstand the system’s pressure, od 150 psi to over 1,000 psi depending on the application.
  • Teplota: Choose materials that can handle the operating temperature, from cryogenic temperatures (-196° C.) to high temperatures (up to 600°C).
  • Média: Consider the compatibility of the valve materials with the fluid being controlled, whether it’s water, chemikálie, or gases.

• Application-Based Selection Criteria:

• • Voda a čištění odpadních vod: Use corrosion-resistant materials like stainless steel to ensure long-term durability.
  • Petrochemické a chemické zpracování: Choose valves with high chemical resistance to withstand aggressive media.
  • HVAC systémy: Opt for lightweight and cost-effective valves to optimize system performance.
  • Průmysl potravin a nápojů: Select valves that meet sanitary standards to ensure food safety and quality.

12. Závěr

Stručně řečeno, butterfly valves are a cornerstone of fluid control technology, offering efficient, reliable performance across various industries.

Whether you are managing water and wastewater treatment, HVAC systémy, or petrochemical processes, butterfly valves offer a reliable and efficient way to control fluid flow.

Pochopení různých typů, materiály, and best practices for installation and maintenance empowers users to maximize the lifespan and functionality of their butterfly valves.

Ultimately improving system efficiency and reducing operational costs.

DEZE is the source supplier of butterfly valves, with its casting foundry, CNC obrábění workshop, and testing laboratory.

If you have any needs for butterfly valves and their accessories, Neváhejte Kontaktujte nás.