What Is a Wafer Check Valve? Types, Working & Advantages

What Is a Wafer Check Valve?

First things first – wafer valves are actually check valves, and their basic functionality is the same. However, they differ in shape and design. 

Wafer check valves are compact and suitable for unconventional installations. These check valves prevent backflow in the piping system and ensure safety. They are lightweight because they require less material. Additionally, wafer check valves require no manual intervention during operation.

Generally, check valves come with flanges. You can install them using these flanges. However, wafer check valves are unique as they don’t have flanges. Instead, they are installed between the pipe flanges. In simple words, they are installed between two pipes using the flanges of those pipes.

This makes wafer check valve installation much easier than that of conventional check valves. In the past, check valves were bigger and heavier. Why? That’s because they used more material for their body. However, wafer check valves are lightweight because they don’t have flanges. This reduces the amount of construction materials they use, making them highly user-friendly.

The basic functionality of wafer and regular check valves is the same. They allow the unidirectional flow of fluids or gases. This means they are used in pipes where you want to ensure one-way flow. If the motor or pump stops working, the fluid won’t be able to come back in the reverse direction. That’s because the disc of these valves automatically closes when the pressure decreases.

Parts of Wafer Check Valves

In the upcoming section, I will discuss the working of these valves. However, it would be challenging to understand how these valves work without knowing their parts. Here are the main parts of a wafer check valve:

• Spring
• Valve Body
• Disc or Plate
• Seat & Sealing Surface

Each of these components is integral to wafer check valve operation. The body is the overall frame, which is made of robust materials. It is a casing that holds all the other parts of these wafer check valves. If this valve body is weaker, it can affect the overall performance and quality of these valves.

The disc is another essential part that opens and closes these valves. When the disc moves, it opens the space to allow the fluid to pass through. When the valve is closed, this disc moves back to the seat, stopping the flow of fluid. It also ensures there is no backflow of the fluid. Wondering how the disc in these wafer valves moves?

That’s because of the spring attached to the disc, which moves it when the pump pushes more fluid and increases the pressure. The seat is the place where the disc rests. The seal, on the other hand, is a rubberized material that comes onto the seat. When the disc closes, this seal seals all the tiny gaps, ensuring no fluid passes through. This seal also prevents gas leakage when the system carries gas rather than fluid.

How Do Wafer Check Valves Work?

A wafer check valve operates automatically based on fluid pressure. The pump pushes the fluid into the piping system. Due to this fluid flow, the pressure inside the pipelines increases. This fluid pressure forces the disc to move away from the seat.

When the disc is moved away, it makes space for the fluid to pass through. When the pressure decreases, the disc begins to return to its original position (the seat of the valve). If fluid pressure decreases suddenly, the disc comes to the seat quickly.

If the fluid pressure decreases gradually, the disc moves smoothly and returns to the seat. Once the disc comes into contact with the valve’s seat, a tight seal is formed. As a result, the fluid or gas cannot pass through. However, the disc that returns to the seat prevents backflow of the liquid.

Types of Wafer Check Valves

Wafer check valves come in various types, but all perform the same function. They differ in design and structure. In the section below, I will discuss some common types of wafer check valves. 

1- Spring-Assisted Wafer Check Valve

These wafer check valves have springs that control the disc’s movement. As I said earlier, the disc or plate is a key component of wafer check valves. This disc moves away from the valve seat, allowing the fluid to pass. It then moves back to the valve’s seat to stop the flow. This movement of the disc is controlled by a spring. This means the disc moves more quickly because the spring is involved. As a result, the working of these check valves is exact.

2- Wafer Swing Check Valve

These wafer check valves don’t have a spring to assist disc movement. Instead, they consist of hinged discs. The movement of this disc is not controlled by elements such as springs. Instead, the fluid pressure pushes it away from the valve seat, which allows the fluid to pass. When the pressure drops to a very low level, the disc returns to its original position. However, the disc’s return to the valve’s seat is generally slow. Why? That’s because no spring could bring it back quickly. So, this slow return of the disc can result in some backflow of the fluid.

3- Wafer Dual Plate Check Valve

These check valves are unconventional as they feature two discs or plates. Typically, wafer check valves feature a single disc that controls fluid flow. However, these valves have two smaller discs. Both of these plates or discs are controlled by the two torsion springs. This means these discs can move very quickly, preventing backflow issues. However, the structure of these check valves is a bit more complex. What sets these wafer check valves apart is their fast operation. Additionally, they effectively prevent backflow.

4- Wafer Lift Check Valve

These wafer check valves differ in how the valve disc moves. They involve the upward (vertical) lifting of the disc, driven by high pressure. If the pressure is moderate or low, the disc may not fully move upward. This can slightly compromise the valve’s performance. Additionally, the disc’s upward movement can be slow, potentially impeding fluid flow during opening. However, when the pressure decreases, the disc moves downward quickly. This ensures no backflow of fluid, making it a superior option.

Advantages of Wafer Check Valve

Wafer check valves are widely used in different industries. They provide consistent performance in all types of piping systems. Here are some key benefits of these wafer check valves:

• Lightweight: First, the wafer check valves are smaller in size than conventional valves. Their compact size makes them an ideal option for even tight spaces. Additionally, they use fewer materials in their construction, making them lightweight.
• Cost-Effective: As mentioned earlier, these valves use fewer materials in their construction. This makes them cost-effective, as manufacturers won’t need large amounts of raw materials. As a result, these wafer check valves are cheaper than many other check valves.
• Easy installation: These wafer check valves are easy to install. The reason is that the overall structure of these valves is simpler. They can be installed between pipe flanges using bolts or nuts. Even someone with basic know-how can install these check valves.
• Easy Availability: Check valves are typically readily available. This is because of their extensive demand and use across different industries. Similarly, wafer check valves are readily available. In fact, all the types of wafer valves are readily available at affordable rates.
• Reliable Performance: One of the significant advantages of wafer check valves is their performance. They perform excellently in addressing backflow issues. The fluid does not flow backwards when the pressure decreases in the piping system. Additionally, you can choose a spring-assisted or dual-disc wafer type for precision performance.

Conclusion

Let’s conclude: check valves are critical in many industries. Their primary function is to prevent fluid from flowing backward in the piping system. The wafer valves are actually a type of check valve that is more compact and lightweight. 

Additionally, these valves offer excellent versatility, which sets them apart. In the article, I discuss the basics of the wafer check valves and their popular types. Remember, each of these wafer valve types differs in terms of their precision and accuracy. You should choose the types that fit your custom piping system.