Considerations When Choosing Swing Check Valves and Wafer Check Valves

Check valves play a vital role in ensuring the one-way flow of fluid and preventing backflow, and are used in a wide range of industries, including oil and gas, water and wastewater treatment, chemical processes, HVAC, petrochemical industry, power generation, Marine and shipbuilding. In these industries, swing check valves and wafer check valves are the most common choices, each with unique design and functional advantages. This article will explore the main differences between the two valves and analyze in detail how they perform in different applications.

Introduction of Swing Check Valve and Wafer Check Valve

What is a Swing Check Valve?

Swing check valve is a type of check valve that controls the flow of fluid through a hinged disc. This valve is usually installed between two pipe flanges and adjusts the flow of fluid through the swing of the valve disc.

Design and Working Principle

The construction of a swing check valve includes a body fitted with a hinged disc. When the fluid flows in the normal direction, the pressure of the fluid pushes away the disc, allowing the fluid to pass smoothly. When the fluid tries to flow in the opposite direction, the disc automatically closes, effectively preventing backflow. This design makes the swing check valve particularly suitable for high-pressure applications where a reliable seal is required.

What is a Wafer Check Valve?

Known for their thin design and lightweight construction, wafer check valves are suitable for applications where space is limited or weight requirements are stringent. It is also installed between the two flanges in the pipe, but its working principle is slightly different from the swing check valve.

Design and Working Principle

Wafer check valves usually consist of a thin disk-shaped body with an internal disc. When the fluid flows in the normal direction, the disc opens to allow the fluid to pass through. However, when the fluid flows in reverse, the disc closes, preventing backflow. Due to their compact design, nip check valves typically have low flow resistance and are suitable for applications that require high flow rates and low pressure drops.

The Main Difference Between Swing Check Valves and Wafer Check Valves

Size and Weight

Wafer check valves are typically designed to be more compact, smaller and lighter. This design gives nip check valves a distinct advantage in space-constrained applications, such as tight duct space or lightweight systems. In contrast, swing check valves are typically larger in volume and weight due to their larger body and complex construction, which can present installation and operational challenges in space-limited environments.

Installation Process

The installation process of the wafer check valve is relatively simple. It is usually sandwiched between two flanges and bolted to complete the installation, which reduces installation time and complexity and is ideal for situations requiring quick installation. In contrast, the installation process of swing check valves is more complicated because they require precise docking and bolting between the two flanges. This process requires greater installation accuracy and time, especially in cases where precise adjustment and adjustment is required, and installation work can become more cumbersome.

Flow Characteristic

Swing check valve design, the swing action of the disc may cause fluid to create a large pressure drop as it passes through. This is because the disc can cause some obstruction to fluid flow during opening and closing, so in systems requiring low pressure drop, swing check valves may not be the best choice.

Wafer check valves are typically designed to achieve less flow resistance, allowing fluid to flow through more smoothly, thereby reducing the overall pressure drop of the system. This makes the wafer check valve particularly suitable for applications where high flow and smooth flow are required.

Performance in Different Applications

Swing check valve because of its excellent sealing performance, especially suitable for high pressure environment. It provides a stable seal that prevents fluid backflow and ensures the safety and reliability of the system under high pressure.

Because of its lightweight design and low drag characteristics, wafer check valves perform better in applications where high flow rates are required and space is limited. It is suitable for a variety of systems that require high flow and have strict limits on installation space, such as HVAC systems and sewage treatment facilities.

Advantages and Disadvantages of Swing Check Valves

The swing check valve has a reliable sealing performance and can effectively prevent the flow back, which makes it especially suitable for high pressure conditions. Its robust structure can withstand high pressure and frequent opening and closing operations, so it is widely used in systems requiring high reliability. However, such valves are usually larger and heavier and may take up more installation space.

The installation process of swing check valves is relatively complex and usually requires precise flange alignment and bolt connection. Due to the swing design of the disc, it may result in a high pressure drop, which has a certain impact on the overall flow rate of the system.

Advantages and Disadvantages of Wafer Check Valves

Known for their compact design and lightweight construction, wafer check valves are suitable for applications where space is limited and weight requirements are stringent. Its design is simple, the installation process is relatively simple and fast, usually only need to be sandwiched between two flanges, which greatly reduces the installation time and difficulty.

Wafer check valves perform well in high-flow applications because of their low flow resistance, which effectively reduces pressure drop. However, compared to swing check valves, the sealing performance of pinch check valves may be slightly inadequate and not suitable for high pressure environments. In addition, its ability to withstand pressure is limited, and it is not suitable for occasions requiring high strength pressure resistance.

Applications of Swing Check Valves and Wafer Check Valves

Swing check valves are commonly used in applications that require high sealing and high pressure tolerance, such as sewage treatment plants, oil and gas pipelines, chemical processing plants, etc. Its rugged construction and reliable sealing performance enable it to operate stably under these harsh conditions.

In contrast, wafer check valves are more suitable for systems where space is limited and high flow is required, such as HVAC systems, sewage treatment facilities, irrigation systems and petrochemical applications. Its lightweight design and low flow resistance make it ideal for these applications.

Considerations When Choosing Swing Check Valves and Wafer Check Valves

When choosing the right check valve, the engineer should consider the following key factors. The first is the pressure level, and the valve that can withstand the corresponding pressure is selected according to the working pressure of the system to ensure the safety and stability of the system. The second is material compatibility, the valve material must be compatible with the conveying medium to prevent corrosion or pollution, thereby extending the service life of the valve. Maintenance needs are also a factor to consider, and choosing valves that are easy to inspect and repair can reduce maintenance costs and improve the long-term efficiency of the system. In addition to considering the initial procurement cost of the valve, it is also necessary to evaluate its long-term operating costs to select the solution that best meets the budget and has reliable performance.