Check valves operating principle

How do check valves work and what are their main applications

Check valves, also called non-return valves, are special types of valves used to control the flow of fluids in a wide range of industrial applications. Their operating principle is relatively simple but extremely effective: they allow the fluid to pass freely in one direction, but prevent its return in the opposite direction. This flow control mechanism is essential in many industrial contexts to ensure the stability and efficiency of processes, ensuring a constant and regulated passage of fluids within pipelines and installations, and preventing the risk of accidents caused by unwanted or overloaded flows in systems. 

 

Let’s see more specifically how the check valves work, what are the main types and applications, and the advantages of their use in industrial environments.

Check valves: operation and characteristics

 

Check valves are essential devices in hydraulic and industrial systems, designed to allow the flow of liquid in only one direction and prevent unwanted reflux. These valves have a closing element, such as a clapet, ball or plate, which is activated to block the reverse flow of the liquid. Often, this closing element is assisted by a spring return, which helps to keep the valve sealed when there is no pressure in the system. 

 

The operation of check valves is based on a simple principle: when the pressure of the liquid exceeds a pre-established threshold, the valve opens allowing the fluid to pass through. Conversely, when the pressure is absent or falls below this threshold, the valve automatically closes, preventing flow in the opposite direction. This prevents and avoids possible contamination or dispersion of liquids, which in some cases could be dangerous or harmful.
Non-return valves are made of corrosion and pressure resistant materials such as brass, bronze or cast iron and can take different shapes depending on the specific requirements of the application. 

 

Main types of check valves

 

Check valves can be divided into different types, each with specific characteristics and applications. Among the most used and widespread valves on the market there are certainly: 

• clapet valves, also known as swing valves, are among the most common and versatile. These valves use a flap that lifts up at the passage of fluids, allowing to regulate their flow. When the pressure of the fluid exceeds a predetermined threshold, the door opens allowing the liquid to pass; on the contrary, when the pressure decreases below this threshold, the disc automatically closes to prevent flow in the opposite direction. Clapet valves are used in a wide range of applications, from water networks to waste systems, due to their simplicity, reliability and effectiveness; 
• wafer valves: wafer valves are designed to be compact and lightweight, taking up little space in the plant, and can be installed in horizontal or vertical piping. These valves are mounted between connecting flanges and do not require the support of a frame or valve body. They use a thin disc that opens and closes to adjust the flow of fluid. Wafer valves are commonly used in heating and cooling systems, HVAC systems, water treatment systems and water recovery plants. Their ease of installation and maintenance makes them ideal solutions in many industrial sectors.

Both types of check valves have distinct technical features and advantages, and the choice between the two depends on the specific requirements of the application, operating conditions and preferences of the plant designer or operator. Relying on a manufacturer of industrial valves with long experience in the sector and offering quality products and with different standards is essential to be able to evaluate the best characteristics for each application and select the options most suitable for specifications Types of use, ensuring the perfect success of each project. 

Main applications of check valves

 

Check or non-return valves are generally used in water systems and plumbing systems and in all cases where there is a need to prevent the flow of water or other fluids, such as oil or corrosive substances, Allowing one-way scrolling. Due to their special characteristics, these valves play a crucial role in ensuring the correct operation of numerous plants and systems, contributing to the safety, efficiency and reliability of industrial operations. In addition to hydraulic systems, the main applications of check valves include: 

• chemical and petrochemical industry, where check valves are used to control the flow of fluids in production, transport and storage processes. These valves are crucial to prevent liquid leakage or contamination during the processing of chemicals and fuels; 
• refrigeration and air conditioning systems, to ensure a unidirectional flow of refrigerants in the cooling circuits. In this case, check valves ensure that the coolant flows only in the desired direction, avoiding leaks and damage to the systems; 
• ventilation and air conditioning systems: in ventilation systems, check valves are used to control the flow of air and prevent the return of polluted or contaminated air into ducts and rooms, Helping to maintain air quality and ensure a safe and healthy working environment; 
• fire safety systems: in fire safety systems, check valves are essential to ensure unidirectional water flow in the fire extinguishing circuits. These valves ensure that water is supplied quickly and effectively to critical points in the event of an emergency.
• waste treatment plants: in waste treatment processes, check valves are essential to prevent the return of harmful or contaminated liquids into collection and treatment systems. These valves ensure that liquids are disposed of safely and in compliance with environmental regulations.

 

ECI check valves: safe and high quality solutions for every application 

 

ECI check valves are safe and reliable solutions for a wide range of industrial applications, ensuring high quality performance and versatility in every operational context. They are designed and manufactured with quality materials, such as brass, bronze and cast iron, to ensure maximum resistance to corrosion, pressure and high temperatures and guarantee a long life in time, minimizing plant downtime and maintenance costs.

 

Built with advanced technology and accurate manufacturing processes, ECI valves offer efficient and precise operation, which is essential to achieve effective flow control in all operating conditions and ensure the safety of industrial processes, minimizing the risk of leakage, contamination or failure.
Another significant advantage of ECI check valves is their versatility and adaptability to a wide range of applications and operating environments. They are available in different sizes, configurations and materials, allowing them to meet the specific needs of each industrial application. Among the various solutions proposed are available both valves for use in water and oil systems, such as the G301 or G303 cast iron check valve, and products also ideal for controlling the flow of air, acids and other corrosive fluids, as the G311 wafer-type check valve, designed to ensure safe and efficient operation of industrial systems.

 

Thanks to a long experience in the sector, ECI European Casting Industry is able to provide specialized advice and tailor-made solutions for each client’s specific needs, offering valves made to different standards and ensuring a wide distribution of its products. 

 

For more information on check valves or other products offered by ECI, contact us!