What Are The Most Common Types Of Valves?

The number and types of valves have grown immensely, contributing much to the safety and performance of industrial operations. 

The Most Common Types Of Valves

The most common types of valves used in industry include ball valves, globe valves, butterfly valves, gate valves and check valves. So let’s look at their usual applications, plus their advantages and disadvantages.

Ball Valves

Ball valves are self-explanatory. They use a ball that allows a junction to be open, closed or partially blocked to control the flow of air or other fluid substances through a system. They’re most common in flow and pressure control applications for gases and liquids, including corrosive fluids and slurries.

Advantages

• Ball valves are ideal for compressed air and gases, providing a reliable and leak-proof seal. 

• They can handle temperatures up to 200°C and pressures up to 700 bars. 

• Their structure is simple, with a compact and low-maintenance design that doesn’t need lubrication.

• They open and close rapidly and offer multi-way design flexibility.

• They’re the most cost-effective valves, with a range of convenient sizes. 

Disadvantages

• Ball valves are unsuitable for precision throttling applications. Their throttling characteristics are poor and can cause erosion on the valve seat.

• Any residual particles in fluid media are liable to collide with and stick to surfaces, causing abrasion, leakage and other problems.

Globe Valves

Globe valves are one of the most popular and widely used industrial valves.  They regulate airflow or fluids using linear motion, adjusting the position of a mobile plug or disc around a stationary ring seat. They consist of a spherical body, split in half around an internal baffle that usually runs parallel to the length of the valve. You’ll find them most commonly in high-temperature applications, where they function as general-purpose flow control valves.

Advantages

• Globe valves offer good full-closing and throttling characteristics, so they’re most often used in throttling applications.

• Their opening and closing time is shorter than other types.

• It’s easy to seat the body ring of a globe valve.

• They can also function as stop-check valves.

• They provide effective flow control with positive shut-off.

• Globe valves have a better ability to minimise leakage.

Disadvantages

• Globe valves often have higher pressure relief.

• A greater force is required to close them under high pressure, which may require an actuator with significant torque.

Butterfly Valves

Butterfly valves have limited control capabilities as they’re operated manually by turning a handle through 90°. They’re specifically designed for flow regulation, employing a metal disc that can be turned perpendicular to the flow to close it off. Fluid flow can be regulated by making intermediate rotations. You’ll find butterfly valves in many different industrial applications, most commonly in food processing, chemical and pharmaceutical services.

Advantages

• Butterfly valves offer great flexibility. They can be operated pneumatically, manually or electronically using gears, handles, or actuators.    

• They’re extremely accurate, highly reliable and need little maintenance.

• They can handle corrosive liquids at low pressures and temperatures.

• They can be used for throttling.

• Butterfly valves can be installed or removed without dismantling the pipe system.

Disadvantages

• You won’t get tight shut-offs with a butterfly valve. 

• Even when fully open, part of the disc will still be exposed to the flow.

Gate Valves

Gate valves are linear motion valves used for the control and isolation of flow. They are most commonly employed for simple on-off applications. They operate by lifting a rectangular or circular gate out of the path of the fluid, so the flow is then unobstructed. The valve dimensions are determined by the pipeline’s bore diameter, which is the same as the gate opening. They’re suitable for high-pressure applications and high-temperature environments.

Advantages

• Gate valves offer minimal pressure loss due to their laminar flow principle.

• When fully open, gate valves provide tight sealing and a low-pressure drop.

• They offer very low friction loss.

• You can use them in a circuit in both directions.

• Gate valves are cost-effective and help save energy.

Disadvantages

• Gate valves may cause vibrations.

• You can’t open or close them quickly.

•  They may leak if irregular high-temperature changes in the system put a load on the pipe’s valve end.

• Their valve seating surfaces are tricky to operate, maintain and repair.

Check Valves

Check valves allow a single direction of flow while preventing backflow in the opposite direction. For this reason, they’re also called non-return valves (NRV). You’ll find them in many manufacturing processes, where they’re commonly used to protect compressors and pumps. They offer an additional layer of protection to a system and can serve as a reliable backup.

Advantages

• Check valves have a simple design and versatile materials. 

• They operate automatically without any manual or automated intervention. 

• The flow velocity controls opening and closing, with the valve opening further as the flow rate increases.

• They sustain pressure and maintain the intended flow direction by preventing backflow.

• They maintain system integrity.

Disadvantages

• You can’t use check valves in pulsating systems where the flow fluctuates.

• The closing element may crash, resulting in excessive wear and potential damage.

More And Different Valves

You have to consider your application carefully when deciding which valves to use. Influencing factors include the fluid medium, operating conditions, flow control requirements and cost. In this article we’ve explained the most common types of valves, but you’ll find many more on the market. 

The demand for industrial valves is increasing due to technological advances in valve design and materials. These include far more complex electronic and intelligent valve control systems to meet the need for progressively intricate industrial processes.