In industrial piping systems, check valves play a crucial role in preventing backflow and ensuring the seamless operation of fluid processes. Among the various types of check valves available, swing check valves and lift check valves are two of the most commonly used. Both serve the same fundamental purpose—allowing fluid to flow in one direction and automatically closing to prevent reverse flow—but their designs and operational mechanisms make them suitable for different applications.

Choosing the right check valve for a specific system can enhance efficiency, minimise maintenance requirements, and improve overall reliability. This article explores the key differences between swing check valves and lift check valves, their working principles, advantages, disadvantages, and the best applications for each type.

 

 What is a Swing Check Valve?

A swing check valve operates using a disc or flap that swings on a hinge or trunnion inside the valve body. When fluid flows in the desired direction, the pressure pushes the disc open, allowing the medium to pass through. If the flow stops or reverses, gravity and backpressure cause the disc to swing back into its closed position, sealing the passage and preventing backflow.

 

Key Features of Swing Check Valves

• Simple Design: The straightforward construction of swing check valves makes them easy to maintain and operate.

• Low Pressure Drop: The swinging motion of the disc results in minimal resistance to fluid flow, reducing pressure loss in the system.

• Suitable for Large Pipelines: Swing check valves are ideal for systems with large pipe diameters due to their unobstructed flow path.

• Horizontal and Vertical Installation: While primarily installed in horizontal pipelines, some designs can function in vertical applications if the flow is upwards.

Advantages of Swing Check Valves

• Efficient for High-Flow Applications: The large opening allows a significant volume of fluid to pass through with minimal turbulence.

• Self-Actuated Mechanism: The valve operates automatically without external assistance, making it energy-efficient.

• Handles Various Media: Swing check valves are compatible with a wide range of fluids, including water, steam, oil, and gases.

Disadvantages of Swing Check Valves

• Slower Response Time: Due to the swinging motion, these valves may take longer to close compared to other types, which can result in slight backflow before sealing.

• Wear and Tear: The continuous movement of the disc can lead to mechanical wear over time, requiring periodic maintenance.
• Not Ideal for Pulsating Flow: Swing check valves may not function effectively in systems where flow is highly variable or pulsating, as the disc can oscillate and cause premature wear.

 

What is a Lift Check Valve?

A lift check valve operates with a disc that moves up and down along a vertical axis within a guided seat. When forward flow occurs, the pressure lifts the disc, allowing fluid to pass. When the flow stops or reverses, gravity and backpressure push the disc back onto its seat, sealing the valve.

 

Key Features of Lift Check Valves

• Disc Moves Perpendicularly to Flow: Unlike the swinging motion in swing check valves, the disc in a lift check valve moves in a linear direction.

• Precise Sealing Mechanism: The guided movement of the disc ensures tight sealing, reducing leakage risks.

• Requires Higher Pressure to Open: Lift check valves generally need higher inlet pressure to lift the disc, making them better suited for high-pressure applications.

• Typically Installed in Horizontal Pipelines: These valves work most effectively in horizontal installations where gravity and flow pressure regulate movement.

Advantages of Lift Check Valves

• Faster Closing Mechanism: The vertical movement of the disc enables quicker sealing, reducing the risk of backflow.

• Effective in High-Pressure Systems: Lift check valves perform well in systems where pressure fluctuations are common.

• Minimal Mechanical Wear: The guided motion of the disc reduces unnecessary movement, leading to longer service life.

Disadvantages of Lift Check Valves

• Higher Pressure Drop: The restricted flow path results in a higher pressure drop compared to swing check valves.

• Limited Size Range: Lift check valves are typically used in smaller to medium-sized pipelines, as their design does not scale as efficiently for large-diameter applications.
• Potential for Sticking: In systems with impurities or viscous fluids, the guided disc may become stuck, leading to performance issues.

 

Comparing Swing Check and Lift Check Valves

Both swing check valves and lift check valves are designed to prevent backflow, but their differences in design, operation, and performance make them suitable for distinct applications.

Feature	Swing Check Valve	Lift Check Valve
Mechanism	Hinged disc swings open/close	Vertically moving disc in a guide
Pressure Drop	Low	Higher than swing check
Closing Speed	Slower	Faster
Best for	Large pipelines, low-pressure systems	High-pressure, pulsating flow applications
Maintenance	Requires periodic checks for wear	Longer lifespan with minimal wear
Installation	Horizontal or vertical (upward)	Primarily horizontal
Application Suitability	Water, steam, oil, gases	High-pressure steam, gases, and refined liquids

Which Valve is Right for Your Application?

Selecting between a swing check valve and a lift check valve depends on several factors, including flow conditions, pressure requirements, and the nature of the medium being transported.

• Choose a Swing Check Valve if:

• • • Your system has a large pipeline diameter.
    • You require a low-pressure drop for efficient flow.
    • The application involves steady, high-volume flow.

• Choose a Lift Check Valve if:

• • Your system operates under high-pressure conditions.
  • You need a faster-closing mechanism to prevent reverse flow.
  • The application involves pulsating or fluctuating flow rates.

Conclusion

Both swing check and lift check valves serve essential roles in preventing backflow in industrial pipelines. The right choice depends on the specific requirements of your system, including pressure levels, flow consistency, and maintenance considerations. Understanding the differences between these valves enables engineers and operators to optimise their processes while ensuring efficiency and longevity.

At SteelStrong Valves, we manufacture high-quality swing check and lift check valves that comply with international standards, offering durability, efficiency, and reliability. With decades of experience in industrial valve manufacturing, our expertise ensures that we deliver superior solutions tailored to the demands of diverse industries. Contact us today to explore our extensive range of check valves and find the perfect fit for your application.