Choosing the Right Valve: A Guide to Selecting Between Fail Close Valve and Fail Open Valve

I. Introduction

Importance of valves in industrial automation systems

In industrial automation systems, valves play a critical role in controlling the flow of fluids and gases through pipelines and other applications. Valves manage direction or control the flow of fluid or gas by opening and closing various passageways. The correct selection and operation of valves are essential in ensuring the reliable and efficient functioning of industrial automation systems. Valves are used in a wide range of industries, including oil and gas, chemical processing, water treatment, and many more. Proper valve selection also ensures the safety of personnel and equipment in these industries, making valves an indispensable component of industrial automation systems.

Brief overview of the two types of valves: fail close valve and fail open valve

People use fail close valves and fail open valves in industrial automation systems.
Fail close valves automatically shut off fluid flow during power failure or emergencies. This ensures that hazardous fluids do not leak out of the system. People design fail open valves to allow fluids to continue flowing when power or signal is lost. Typically, people use fail open valves in applications where maintaining fluid flow is more important than shutting it off during power failure. Choosing the correct valve for a specific application is critical in ensuring the safety, efficiency, and reliability of industrial automation systems.

II. Fail Close Valves

Definition and explanation of fail close valves

Fail close valves, as the name suggests, are valves designed to close or stop the flow of fluid automatically when there is a power failure or an emergency. These valves use a spring mechanism or other fail-safe technology that forces the valve to shut off in the event of a power loss or signal failure. People commonly use fail close valves to automatically shut off fluid flow during emergencies or power failures. One example of the use of fail close valves is in chemical processing plants where hazardous or toxic fluids are transported. Fail close valves require minimal maintenance and have a long service life, making them a cost-effective solution for many industrial automation systems.

Types of applications where fail close valves are commonly used

People commonly use fail close valves to automatically shut off fluid flow during power failure or emergencies in critical applications. Chemical processing plants transporting hazardous or toxic fluids is one example of such applications. Fail close valves prevent fluid leaks during power failure. They prevent environmental disasters in oil and gas processing. Firefighting systems use fail close valves to ensure availability of water. Power plants, nuclear facilities, and critical infrastructure rely on fail close valves.

Advantages and disadvantages of fail close valves

Fail close valves offer several advantages in industrial automation systems. These valves provide automatic shutoff in the event of a power failure or emergency, ensuring that hazardous or toxic fluids do not leak out of the system. Fail close valves also require minimal maintenance and have a long service life, making them a cost-effective solution for many applications. However, there are also some disadvantages to fail close valves. Fail close valves may not maintain fluid flow during power failure. They are complex and expensive for some applications. Calibration and testing ensure correct emergency function, adding cost and time.

Examples of fail close valves

There are several types of fail close valves that are commonly used in industrial automation systems. Globe valves, gate valves, diaphragm valves and ball valves are just a few examples. Typically, people use globe valves for high-pressure applications with precise fluid flow control. People use gate valves when there is a need for full flow isolation in an application. People use diaphragm valves for high purity fluids or corrosive/abrasive fluids and use ball valves in low and high-pressure applications due to their durable design.
Several factors, including fluid transport, pressure, temperature requirements, and environmental conditions, affect the choice of fail close valve.

III. Fail Open Valves

Definition and explanation of fail open valves

Fail open valves are valves that remain open when there is a power failure or signal loss. Fail open valves use fail-safe technology to remain open during power loss. Use fail open valves where maintaining fluid flow is critical. Cooling systems may use fail open valves to prevent equipment damage. Consider fluid characteristics and application requirements before selecting a fail open valve.

IV. Factors to Consider When Selecting a Valve

Selecting a valve for industrial automation requires considering several factors. Fluid type, viscosity, pressure, temperature, and environmental conditions are essential. Flow rate and pressure drop are also critical for selecting the right valve. Consider the level of control required over fluid flow. Valve safety and reliability are critical, especially in hazardous applications. Evaluate cost and maintenance requirements for a cost-effective solution. By considering these factors, select a valve that meets application requirements.

V. Conclusion

In conclusion, selecting the right valve is a critical decision when designing an industrial automation system. The two primary types of valves to consider are fail close valves and fail open valves. Fail close valves shut off fluid flow in the event of a power failure or signal loss, while fail open valves maintain fluid flow. The choice between these two types of valves depends on the specific requirements of the application. Factors to consider include the type of fluid being transported. Environmental conditions, required flow rate, and pressure drop also matter. Level of control, safety, reliability, cost, and maintenance are other considerations. By evaluating these factors, select the appropriate valve for optimal performance and reliability. Consult a qualified valve manufacturer or supplier to ensure the valve meets all requirements.