Introduction to Water and wastewater gate valves

What Is a Gate Valve?

A gate valve is a type of isolation valve used to control the flow of liquids by raising or lowering a gate inside the valve body. When fully open, the gate allows for unobstructed flow, resulting in minimal pressure loss. Gate valves are not intended for flow regulation but are ideal for applications requiring a straight-line flow of fluid with minimal restriction. They are commonly used in water supply, wastewater treatment, irrigation, and fire protection systems.

How Gate Valves Work?

Gate valves operate by moving a wedge-shaped gate up or down perpendicular to the flow of the fluid. This movement is typically achieved through a threaded stem connected to a handwheel or actuator. When the gate is lifted, the valve opens, allowing fluid to pass through; when the gate is lowered, it blocks the flow. This design ensures a tight seal when closed and minimal pressure drop when open. 

Key Features and Benefits of AVK UK Gate Valves

• Resilient Seated Design: AVK's gate valves feature a resilient seated design, where the gate is fully encapsulated in rubber. This ensures a tight seal, even in the presence of impurities, and prevents corrosion of the gate core.
• High-Quality Rubber Compounds: The rubber used in AVK valves has excellent compression set properties, allowing it to regain its original shape after compression. This ensures long-term sealing performance and reduces the risk of leakage.
• Triple Stem Sealing System: AVK gate valves incorporate a triple stem sealing system, including an NBR wiper ring, multiple O-rings, and a rubber manchette. This design provides superior protection against external contaminants and internal leakage.
• Corrosion Protection: The valves are coated with a high-quality epoxy coating, providing excellent resistance to corrosion and ensuring a long service life, even in aggressive environments.
• Smart Water Integration: AVK's gate valves can be integrated with Smart Water technologies, allowing for remote monitoring and control, which enhances operational efficiency and reduces maintenance costs.

Types of AVK UK Gate Valves

• Resilient Seated Gate Valves. These valves feature a ductile iron body with a fully rubber-encapsulated wedge, providing excellent sealing capabilities and resistance to corrosion. They are suitable for potable water and wastewater applications and are available in various sizes and pressure ratings.
• Metal Seated Gate Valves. Designed for applications involving higher temperatures or higher solid content, metal seated gate valves have a durable metal-to-metal sealing surface. They are ideal for certain wastewater and industrial applications where resilient seated valves may not be suitable.
• PE-Tailed Gate Valves (Series 36). The Series 36 gate valves come with factory-fitted polyethylene tails, allowing for electrofusion welding directly to PE pipelines. This design eliminates potential leak paths associated with flanged connections, reduces installation time by up to 40%, and minimizes environmental impact by reducing plastic packaging by 71%. 
• Knife Gate Valves. Suitable for handling sludge, wastewater, and other challenging media, knife gate valves have a sharp-edged gate that can cut through thick fluids. They are commonly used in wastewater treatment plants, mining, and pulp industries. 

Materials Used in AVK UK Gate Valves

• Body: Typically made from ductile iron (GJS-500-7), offering high strength and durability. 
• Wedge: Constructed from ductile iron and fully encapsulated in EPDM rubber for resilient seated valves or made from ductile iron with metal seating surfaces for metal seated valves. 
• Stem: Manufactured from stainless steel (grades 1.4021 or 1.4401/316), providing excellent corrosion resistance. 
• Sealing Components: Utilize high-quality EPDM or NBR rubber compounds, ensuring reliable sealing performance and compliance with drinking water standards. 
  
  

Choosing the Right Gate Valve. When selecting a gate valve, consider the following factors:

• Application: Determine whether the valve will be used for potable water, wastewater, or industrial applications.
• Pressure and Temperature Requirements: Ensure the valve can withstand the system's operating pressure and temperature.
• Installation Environment: Consider whether the valve will be installed above or below ground and select appropriate coatings and materials accordingly.
• Connection Type: Choose between flanged, PE-tailed, or other connection types based on the pipeline system. 
• Compliance and Approvals: Verify that the valve meets relevant standards and approvals, such as WRAS, DVGW, or KIWA, especially for drinking water applications 
  
  

Why Choose AVK UK?

• Proven Expertise: As part of the globally renowned AVK Group, AVK UK brings decades of experience in valve manufacturing and innovation. 
• Quality Assurance: AVK UK products are manufactured to the highest standards, with rigorous testing and quality control processes ensuring reliability and longevity.
• Sustainability Focus: AVK UK is committed to environmentally responsible practices, offering products that reduce water loss, minimize waste, and support sustainable infrastructure development.
• Innovation and Integration: AVK UK's integration of Smart Water technologies enables remote monitoring and control, enhancing system efficiency and reducing operational costs.