What are Gate, Globe and Check Valves?

Valves are an essential component in many industries, but do you know the differences between gate, globe, and check valves? Understanding these types of valves is crucial for selecting the right one for your specific application.

What is a Gate Valve?

Gate Valves are a type of valve that is used to control the flow of a fluid or gas by opening and closing a gate or wedge that is placed between two parallel seats. These valves are common in industrial settings, where they are used to control the flow of liquids or gases in pipelines, tanks, and other equipment.

There are several different types of Gate Valves, including rising stem valves, non-rising stem valves, and wedge disc valves, each of which is designed to meet specific industry needs and requirements.

What is a Globe Valve?

Globe valves are a type of mechanical valve that regulates fluid flow in a piping system. They consist of a movable disk or plug that regulates flow through the valve by being raised or lowered onto a stationary ring-shaped seat. The shape of the valve body resembles a globe, hence the name “globe valve.”

What is a Check Valve?

Check valves are also known as non-return valves or one-way valves. They are mechanical valves that allow fluid or gas to flow in one direction only and prevent the backflow of the same. These valves operate automatically and do not require any external power source to function.

They are widely used in piping systems, pumps, and compressors, among others, to maintain the proper flow direction and prevent damage to equipment and processes.

Check valves come in different types, such as ball check valves, swing check valves, and lift check valves. Each type has its unique features and applications in the industry. Ball check valves use a ball or sphere to block the flow in the opposite direction, while swing check valves use a hinged disc to prevent backflow.

Lift check valves, on the other hand, use a piston or a similar mechanism to lift and close the valve when the flow reverses.

How do Gate, Globe and Check Valves Work?

Gate Valves

Gate valves work by using a gate or wedge to control the flow of fluid through a pipe. As the gate is lifted or lowered, the fluid flow is either allowed or blocked. This process is achieved by using a threaded stem that connects the gate to the valve’s actuator, allowing the user to control the flow.

Globe Valves

Globe valves work by controlling the flow of fluid or gas through a pipe by using a movable disk to regulate the opening and closing of the valve. This disk, known as a plug or a disc, is located in the middle of the valve in a chamber known as the valve body.

The valve body contains an inlet and an outlet section, with the plug positioned in between. When the valve is open, the plug is lifted off the seat, allowing the fluid or gas to pass through the valve and into the outlet section of the pipe. When the valve is closed, the plug is pressed down onto the seat, creating a seal that prevents any fluid or gas from passing through.

The valve stem controls the movement of the plug in the valve. When the stem is turned, it moves the plug up or down, opening or closing the valve. This movement can be manual or automatic, with many valves using an actuator to automate the process.

Check Valves / Non Return Valves

Check valves operate on the principle of differential pressure. When the pressure on the inlet side of the valve is greater than the pressure on the outlet side, the valve opens and allows the fluid to flow through. However, when the pressure on the outlet side is greater, the valve closes, preventing the backflow of fluid.

Check valves come in different types, including swing check valves, ball check valves, and diaphragm check valves. Each type has a unique design and functionality that makes it suitable for specific applications.

For instance, swing check valves have a swinging disc that opens and closes depending on the pressure differential across the valve. Ball check valves, on the other hand, have a floating ball that moves up and down to control the flow of fluid.

Where are Gate, Globe and Check Valves Commonly Used?

Gate Valves

Gate valves are commonly used in various industries and applications where isolation and control of fluid or gas flow is necessary. These valves are particularly effective in applications where a straight-line flow of fluid or gas with minimum restriction is required.

They are widely used in the oil and gas industry for controlling the flow of crude oil, natural gas, and other hydrocarbons. They are also commonly used in the water treatment industry for isolating and controlling the flow of water in pipelines and treatment plants. Moreover, gate valves are used in the chemical and petrochemical industry, power generation, and HVAC systems.

The reason why gate valves are commonly used in these industries is that they provide a tight seal when closed, preventing leakage and minimising the risk of contamination. They are also durable and can withstand high pressure and temperatures.

Globe Valves

Globe valves are widely used in industries such as oil and gas, power generation, chemical, pharmaceutical, and water treatment. These valves are designed to regulate and control the flow of fluids, gases, and steam in pipelines. They are used in high-pressure and high-temperature applications where precision and accuracy are essential.

In the oil and gas industry, globe valves are used for several purposes, including flow control, shut off, and regulation. They are commonly found in pipelines, refineries, and chemical plants. In power generation, globe valves are used in steam turbines to control the flow of steam. They are also used in cooling water systems and as safety valves.

In the chemical industry, globe valves are used to control the flow of chemicals in various processes. They are also used in pharmaceutical manufacturing to regulate the flow of liquids and gases. In the water treatment industry, globe valves are used in water supply and wastewater treatment systems.

Check Valves

Check valves are commonly used in various industries, including oil and gas, water treatment, chemical processing, and more.

In the oil and gas industry, check valves are used in pipelines to prevent backflow and ensure the safe transportation of fluids such as crude oil and natural gas. They are also used in drilling applications to prevent the loss of drilling fluids.

In water treatment plants, check valves are used to control the flow of water and prevent backflow, which could contaminate the water supply. They are also used in irrigation systems to ensure that water flows only in the intended direction.

In chemical processing plants, check valves are used to prevent the mixing of fluids that could cause dangerous reactions. They are also used in pharmaceutical production to ensure that only the correct materials are used in the manufacturing process.

Is a Gate, Globe or Check Valve Right for Your Application?

Gate valves are designed for full open or full close applications. They are ideal for applications that require a tight seal to prevent leakage.

Globe valves, on the other hand, are designed for throttling or regulating flow. Globe valves are ideal for applications that require precise control over the flow rate.

Check valves, also known as non-return valves, are designed to prevent backflow or reverse flow. They allow the fluid to flow in one direction only and automatically close to prevent the backflow of the fluid.

What is the Difference Between a Gate Valve, Globe Valve and Check Valve?

Gate valves are designed for on/off applications, providing a tight seal when closed and a full flow when open. They have a flat or wedge-shaped gate that slides up and down to control the flow of fluid or gas and typically have low pressure drop.

Globe valves, on the other hand, are designed for regulating flow, rather than simply turning it on or off. They have a movable disk that controls flow by changing its position relative to the seat. Globe valves can be used for both throttling and isolation applications.

Check valves, as their name suggests, are designed to prevent backflow. They allow fluid or gas to flow in only one direction, automatically closing to prevent reverse flow. Check valves are often used in applications where backflow could cause damage or contamination.

What are the Advantages and Disadvantages of Using Gate Valves?

Gate Valves

Like any other type of valve, gate valves have their advantages and disadvantages.

Advantages

High Flow Capacity: Gate valves have a full-bore design, which means they have minimal obstruction to the flow path, providing high flow capacity.

Tight Sealing: The design of the gate valve allows for tight sealing, which ensures that there are no leaks in the pipeline system.

Durability: Gate valves are made of robust materials, such as cast iron, stainless steel or brass, which makes them highly durable and resistant to wear and tear.

Low Pressure Drop: Gate valves provide a low-pressure drop, which means that there is less energy loss during fluid flow.

Disadvantages

Slow Opening/Closing: Gate valves require multiple turns of the handwheel or operating mechanism to open or close fully, which can be time-consuming.

Not Suitable for Throttling: Gate valves are not suitable for regulating the flow rate as they are either fully open or fully closed.

Prone to Clogging: Gate valves are prone to clogging due to their design, which can obstruct the flow path and lead to blockages.

High Maintenance Cost: Gate valves require frequent maintenance to prevent corrosion and wear, which can be costly.

Globe Valves

Globe valves offer several advantages and disadvantages that should be taken into account before selecting and installing them.

Advantages

Precise Control: Globe valves offer precise and accurate flow control, making them ideal for applications that require precise flow regulation.

Versatility: They can be used in a variety of applications, including high-pressure and high-temperature environments.

Easy Maintenance: Globe valves are easy to maintain and repair, with interchangeable parts and simple construction.

Low Leakage: Globe valves have a low leakage rate, making them ideal for applications that require tight shutoff.

Disadvantages

Pressure Drop: Globe valves have a higher pressure drop compared to other types of valves, which can reduce the overall efficiency of the system.

Slower Operation: Globe valves have a slower operation compared to other types of valves, which can be a disadvantage in applications that require quick response times.

Higher Cost: Globe valves can be more expensive compared to other types of valves, especially in larger sizes.

Limited Flow Capacity: Globe valves have a limited flow capacity compared to other types of valves, which can limit their use in applications that require high flow rates.

Check Valves

While check valves provide several benefits, there are also some drawbacks to using them.

Advantages

Backflow Prevention: Check valves ensure that fluids flow only in one direction, preventing backflow, which can cause significant damage to the system.

Reduced Maintenance: The installation of check valves reduces the need for frequent maintenance, as they help to prevent clogs and blockages that can occur as a result of backflow.

Improved Efficiency: Check valves can help to improve the efficiency of the system by reducing pressure loss and minimising the amount of energy required to pump fluids through the system.

Cost-Effective: Check valves are relatively inexpensive and provide significant cost savings over time, thanks to their ability to prevent damage and reduce the need for maintenance.

Disadvantages

Pressure Drop: Check valves can cause pressure drops due to their design, which creates resistance to fluid flow.

Noise: Some check valves can produce noise when they close, which can be a nuisance to those nearby.

Limited Application: Check valves are limited in their application as they are only suitable for use in systems where backflow prevention is necessary.

Difficulty in Maintenance: Check valves can be difficult to maintain due to their design, which makes it difficult to access and clean internal parts.

Conclusion

In conclusion, gate, globe, and check valves may seem like a small part of a larger system, but they play a crucial role in ensuring the safety and efficiency of many industries. Understanding the differences between them can help you make informed decisions when choosing the right valve for your needs.

So, whether you’re in the oil and gas industry or just curious about how things work, remember that these valves are the unsung heroes that keep things flowing smoothly.

Next up, gate valves vs butterfly valves: understanding the key differences