How Diaphragm Check Valves Work

01-02-23

Diaphragm Check Valves

You might use diaphragm check valves often in your business, but do you know how they work? This is key to understanding how to properly maintain and repair them when necessary. Check valves are present in many industries, and they use various methods to control the flow of gases or liquids.

They open and close quickly, which allows for precise control over the flow. There are many different types of check valves, each with its own advantages. In this blog post, we will explore the types of diaphragm check valves and how they operate.

What Are Diaphragm Check Valves?

Diaphragm check valves, sometimes referred to as one-way valves use a flexible diaphragm to control the flow of fluid. They are popular in industrial applications because they are durable and can handle high pressures and temperatures.

How Do Diaphragm Check Valves Work?

As the name implies, diaphragm check valves have a diaphragm that controls the flow. When fluid pressure is applied to the valve from the inlet side, the diaphragm forces open, allowing fluid to flow through.

Once the fluid pressure lessens, the diaphragm closes, preventing any backflow. This makes diaphragm check valves ideal for preventing reverse flow in systems where that could be dangerous.

Types Of Diaphragm Check Valves

There are two main types of diaphragm check valves, free-floating valves, and fixed-floating valves. There are some others that we will also look at below.

Free-floating Diaphragm Valves

Also known as floating ball valves, these are one of the most popular types of valves used in a wide variety of industries. A free-floating ball is held in place by a retainer and sealed with a seat. As fluid flows through the valve, the ball floats on top of the fluid and seals against the seat, preventing flow through the valve.

Free-floating diaphragm valves are used for applications where tight shut-off is not required, such as in water and air systems. They are available in a wide variety of materials, including brass, stainless steel, and plastic. They are also available in a wide range of sizes, from 1/4″ to 6″.

Free-floating diaphragm valves are typically used in low-pressure applications.

Some of the advantages of free-floating diaphragm valves include:

  • They are easy to operate and maintain
  • They have a wide range of material options
  • They are available in a wide range of sizes
  • They are typically used in low-pressure applications

Some of the disadvantages of free-floating diaphragm valves include:

  • They may not provide a tight seal
  • They may not be suitable for high-pressure applications
  • They may not be suitable for applications where a tight shut-off is required

Fixed Flexing Valves

Fixed flexing valves are similar to free-floating check valves, but with one main difference: the disc is attached to the valve body via a flexible hinge. This design allows for the disc to seal more tightly against the valve seat, providing better protection against backflow. These valves are often used in applications where there is a higher risk of backflow, such as in sewage lines.

Fixed flexing check valves are often used in pipelines to prevent process fluids from flowing back into pumps or other equipment. They are often also used in applications where there is a higher risk of backflow, such as in sewage lines.

Their disadvantages include being more difficult to operate and maintain than other types of check valves. They may also not be suitable for high-pressure applications.

Poppet Valves

Poppet valves have a disc that moves up and down to open and close the valve. These are often used in automotive applications, such as fuel injectors.

Ball Valves

Ball valves have a ball with a hole through the middle that opens and closes to control flow. These are commonly used in plumbing applications.

Needle Valves

Needle valves have a needle that is inserted into a seat to open and close the valve. These are often used in gas lines and other applications where a very small opening is needed.

When to Use a Diaphragm Check Valve

There are many reasons you might need a diaphragm check valve. Some of the most common reasons include:

Preventing Backflow

One of the most common reasons to use a diaphragm check valve is to prevent backflow. This is especially important in applications where backflow could be dangerous, such as with fuel lines or chemicals.

Maintaining Pressure

Another reason to use a diaphragm check valve is to maintain pressure in a system. This is often done in HVAC systems or other situations where its important to keep pressure from escaping.

Regulating Flow

In some cases, you may need to regulate the flow of liquids or gases through a system. This is often done with needle valves, which allow you to control the size of the opening. This is important in systems where a precise flow rate is necessary, such as in medical applications.

Industries That Use Diaphragm Check Valves

When used in the automotive industry, these valves are often used in fuel and oil lines. These valves are also used in construction, specifically in irrigation systems.

In the industrial sector, fixed flexing valves are used in a variety of applications, such as water treatment plants and paper mills. One of the most common uses for these valves is in fuel lines.

These valves are also used in oil lines, specifically to block the flow of oil when it is flowing in the wrong direction. Fixed flexing valves are also used in water treatment plants to control the flow of water.

Pros and Cons of Diaphragm Check Valves

When it comes to diaphragm check valves, there are both pros and cons to consider. Some of the main pros include:

  • Simple design
  • Low cost
  • Easy to install and maintain
  • Can be used in a variety of applications

On the other hand they:

  • Not suitable for high-pressure applications
  • Can be noisy when in use
  • Can become jammed if debris gets caught in the disc
  • Not as durable as other types of valves

So it’s important to know and understand both the pros and cons before deciding if a diaphragm check valve is the right choice for your application.

Shop Quality Diaphragm Check Valves

Diaphragm check valves are durable and can handle high pressures and temperatures. They are also easy to maintain and have a simple design. They are not affected by corrosion or deposits, which means they will last longer than other types of valves.

If you are in need of a reliable check valve for your industrial application, consider a diaphragm check valve. They are an excellent choice for many industries and can provide you with years of trouble-free service. Request a quote for your project from us today.

Back to News