Gate Valve vs Check Valve: Discovering the Differences

Last Updated on July 2, 2023

For anyone working with pressurized liquids and gases, the importance of valves can’t be overstated. They’re an essential component in controlling flow.

But do you know how to choose between a gate valve and a check valve for your particular application? These two types of fluid handling systems have distinct design, function and their own unique purposes.

Gate valves give you manual control to open or close the flow of liquids and gases, while check valves are designed with clever functionality. They protect your pipes from harmful backflow by automatically opening when pressure rises.

Make sure you’re always making a well-informed decision regarding plumbing projects, water treatment systems and industrial processes. Stay tuned as we explore the two main types of valves and uncover how they compare. We’ll help you select which one is right for your specific project.

How They Work

Gate valves and check valves are two different types of valves that serve specific purposes in fluid flow control.

Gate valves work by sliding a gate-like component, also known as a wedge, into or out of the flow path to start or stop the flow. The gate can be fully opened or fully closed, making it a great option for isolation or full-bore flow control.

When the valve is fully open, the gate is lifted entirely out of the way, allowing the fluid to flow freely through the valve body.

On the other hand, check valves are designed to prevent reverse flow in a piping system. They work by using a swinging or lift-style disc, also known as a clapper, to close automatically when fluid flows in the reverse direction.

Check valves rely on the flow of fluid to open the valve, allowing forward flow, and close it when the flow stops or reverses. The disc in a check valve can be spring-loaded to close more quickly, or it can rely solely on the flow of fluid to close.

Basically, gate valves control fluid flow by fully opening or closing the path, and check valves prevent reverse flow by closing and opening based on flow direction in a piping system.

Design and Structure

Gate valves and check valves differ in design and structure, which determine the specific function each valve serves in a piping system.

It’s a valve with a gate-like component, also called a wedge, that moves into or out of the flow path. The wedge can be made from different materials, including brass, cast iron, stainless steel, or plastic, depending on the controlled fluid and operating conditions.

The valve body is typically made of the same material as the wedge and is threaded at both ends to allow for easy installation in a piping system. Gate valves are often cylindrical in shape and have a long stem that extends through the valve body and into the piping system.

Check valves, on the other hand, have a disc-like component, also known as a clapper, that moves back and forth in response to fluid flow. The clapper can be made of materials such as brass, stainless steel, or plastic and is usually hinged or mounted on a spring. 

For installation in a piping system, it’s usually threaded at both ends and made of the same material as the clapper. Check valves are often compact in size and can be designed to fit into tight spaces in a piping system.

Briefly, gate valves are gate-like components that move into and out of flow paths, while check valves are disc-like components that move back and forth. Every valve serves a specific function in a piping system based on its design and structure.

Types

When it comes to regulating fluid flow in a piping system, gate valves and check valves are two commonly used types of valves. Each of these valves comes in different types, depending on the specific application requirements and operating conditions.

Gate valves are available in several types, including:

Rising Stem Gate Valve: This type of valve has a stem that rises as the valve is opened, making it easy to see the valve’s open or closed position.

Non-Rising Stem Gate Valve: Non-Rising Stem Gate Valve: Use this type of valve when space is limited since the stem doesn’t rise as it opens.

Solid Wedge Gate Valve: This type of valve has a solid wedge that moves into or out of the flow path, making it suitable for use in high-pressure applications.

Flexible Wedge Gate Valve: With a flexible wedge that moves in and out of the flow path, this type of valve works well when fluid pressure is uneven.

Check valves also come in several types, including:

Swing Check Valve: This type of valve has a disc-like component that swings open and closed in response to fluid flow, making it suitable for use in low-pressure applications.

Ball Check Valve: This ball-like component moves into and out of the flow path depending on fluid flow.

Dual Plate Check Valve: Dual plate check valves move when there’s fluid flow, making them good for small spaces.

Globe Check Valve: With its globe-like body, this type of valve is ideal for high-pressure applications with sudden changes in fluid flow.

Function and Application

Gate valves and check valves play crucial roles in fluid handling systems but have different functions and applications.

Gate valves: They’re designed to control the flow of fluid by opening or closing the flow path. Think of it like a faucet – when you turn the handle, the flow of water is either allowed or restricted. This makes gate valves ideal for situations where you need to turn the flow of fluid off completely. 

For example, in water distribution systems or industrial pipelines, you might use a gate valve to stop the flow of fluid altogether.

Check valves: These valves are all about preventing backflow. You see, sometimes fluid can start flowing in the reverse direction, and check valves are designed to stop that from happening. You’ll often find check valves in places like water treatment plants, pumping stations, or irrigation systems, where backflow could be a problem. How do they work? 

Well, the valve only allows fluid to flow in one direction. If fluid starts to move in the opposite direction, a component inside the valve, called a clapper, moves to close off the flow path and prevent backflow.

So, to sum it up, gate valves control the flow of fluid and check valves to prevent backflow. They each have unique features and are used in different situations depending on the specific function they need to serve.

Cost

The cost of a gate valve and a check valve can vary greatly based on various factors such as the material they are constructed with, their size, and the manufacturer. In general, gate valves tend to cost more compared to check valves.

Gate valves are usually made from materials like cast iron, brass, or stainless steel, which contribute to their higher cost. Their larger size and complex design also drive up their manufacturing cost. On the other hand, check valves are often smaller and less complicated, making them less expensive to produce.

It’s important to note that the cost can vary greatly even within the same type of valve. For instance, a large gate valve made of high-end stainless steel can be more expensive than a small check valve made of plastic.

The brand you choose can also affect the cost, as some well-known brands may offer high-quality valves but at a higher price, while others offer more budget-friendly options.

While gate valves are typically more costly than check valves, the final cost will depend on several factors. It’s crucial to take these factors into consideration when selecting the right valve for your fluid handling system.

Similarities

Gate valves and check valves both play an important role in controlling the flow of fluids or gases in a piping system. Despite their differences in design and function, these two types of valves have a number of similarities that make them suitable for many common applications.

One of the main similarities between gate valves and check valves is their construction material. Both types of valves can be made from a variety of materials, including brass, cast iron, stainless steel, and plastic, to suit the needs of different applications and operating conditions.

Another similarity is the ease of installation. Both gate valves and check valves are threaded at both ends, making installing them in a piping system simple. Furthermore, both types of valves are available in a range of sizes, making it possible to select one that fits the space constraints of a particular application.

Both gate valves and check valves can also be designed to handle a variety of fluids and gases, including water, oil, and gases like air and natural gas. This versatility makes these types of valves ideal for use in a variety of industries, including petrochemical, plumbing, and HVAC.

Advantages and Disadvantages

Gate valves and check valves are both commonly used in fluid handling systems, but each has its own unique advantages and disadvantages.

Advantages of Gate Valves

Positive shutoff: Gate valves have a tight seal when closed, ensuring no fluid can pass through.

Durable: Gate valves are made of heavy-duty materials, making them durable and long-lasting.

Adjustable flow control: Gate valves can be adjusted to control the flow of fluid.

Versatile: Gate valves are available in a range of materials, sizes, and pressure ratings, making them suitable for a variety of applications.

Disadvantages of Gate Valves

Slow operation: Gate valves require more time to open and close than other types of valves.

Difficult to repair: Repairing a gate valve can be a complex and time-consuming process.

Not suitable for high-pressure applications: High pressure can cause damage to the gate, making it unsuitable for high-pressure applications.

Advantages of Check Valves

Simple design: Check valves have a simple design, making them easy to repair and maintain.

Fast operation: Check valves are designed to open and close quickly, making them suitable for high-speed applications.

Cost-effective: Check valves are relatively inexpensive compared to other types of valves.

Compact design: Compact design: You can fit check valves into tight spaces in piping systems.

Disadvantages of Check Valves

Limited flow control: Check valves do not provide a means of adjusting the flow of fluid.

Potential for leakage: Check valves can leak if they become damaged or worn.

Limited durability: Check valves are less durable than gate valves and may need replacing more frequently.

What comes first, the check valve or the gate valve?

It depends on the specific application and system design. Generally, a check valve is installed to prevent backflow in a pipeline, while a gate valve is used to regulate or stop fluid flow. 

The order in which they are installed will depend on the system’s specific requirements, and both can be installed in different positions within the pipeline.

When should we use a check valve?

Check valves are often installed on pump discharge lines to prevent liquid flow reversal with the succession of pumping, and foot valves, which are a form of check valves, are usually installed in the pump suction line.

In order to prevent turbulence and rattling, check valves should be located several straight pipe diameters upstream of circulators, elbows, tees, and strainers.

It is also recommended to tag valves that are part of a larger system with an identifying label for easier identification and management.

Additionally, check valves are used in fluid process control valves to manage the flow rates of fluids, liquids, or gases and temperature, pressure, and level. In a multi-zone closed system, check valves are used to focus water pressure as specifically as possible by closing off all zones except one.

It is recommended to check pressure relief valves every two months and replace defective valves if a repair or resetting is indicated.

When would you use a gate valve?

A gate valve is used when there is a need for a straight-line flow of fluid with minimal restriction. The valve opens and closes by lifting a rectangular gate out of the fluid path, making it a complete on-and-off valve. 

The design of the gate is wedge-shaped and does not allow for flow regulation, but the multi-turn design of the stem minimizes pressure loss and prevents water hammering. Gate valves are used in industrial applications such as water and gas lines and can also be found in residential settings.

Do check valves hold pressure?

Check valves are designed to hold pressure in a piping system by allowing fluid to flow in one direction and preventing reverse flow. They help maintain a consistent flow direction and pressure in a pipeline.

The Final Verdict: Which Valve is Right for Your Application?

Gate valves and check valves are two essential components in fluid handling systems, each with its own unique function and application. 

Gate valves are designed to control the flow of liquids or gases by manual operation, while check valves prevent backflow by automatically opening and closing based on fluid pressure. The choice between the two depends on specific system requirements and operational needs.

Knowing the ins and outs of gate valves and check valves can help you make an educated choice. Each has its own set of pros but also cons. So understanding these differences will guide you toward a reliable solution that meets all your fluid handling requirements.

Last update on 2023-12-05 / Affiliate links / Images from Amazon Product Advertising API