How Does an Excess Flow Check Valves Work?

Safety is one of the primary concerns in any industrial plant, commercial or residential space. And safety devices such as different types of valves are used in industrial units to manage the flow of liquids and gases. Excess Flow valves or EFVs are designed by excess flow check valve manufacturers for a variety of industrial requirements.

Purpose of Excess Flow Check Valves

As the name suggests, an excess flow check valve closes only when the force of the liquid or gas passing through the valve exceeds the power of the spring holding it open. Excess flow valves are mechanical safety devices installed inside natural gas service lines to control the flow of the liquids or gases.

Leading excess flow check valve manufacturers in India can design customised valves on the basis of client specifications. Some of the types of EFVs that can be utilised are screwed, flanged, internal and sandwich type valves.

How does an EFV work?

• If there is an EFV requirement, excess flow check valve manufacturers study the needs of the client and discuss the design with their teams. The EFV has to be customised for certain projects depending on the required pressure settings, end connections, material used and other parameters.
• Generally, the valve is placed under the ground with the service line. It is connected to a meter above the ground with pressure reading taken by service line technical experts.
• The body of the excess flow check valve is consists of a sleeve, keepers, spring, guide and poppet. Under normal conditions, the valve is kept open by the spring. But if there is a rupture in the service line carrying the gas, the pressure of the flow of the liquid or gas passing through the valve increases.
• Based on the functional output desired from the valve, the valve is set to close or trip if the spring experiences a pressure that exceeds the safety limit. The pressure of the spring can be noted on the meter connected to the spring.
• The valve opens up when the pressure level is restored to the safety limit that it was designed for.

So, the excess flow check valve ensures safety by stopping the flow of excess gas or liquid into the atmosphere and causing damage to life and property. But what needs to be noted is that, an excess flow check valve will not shut if there is a leakage or any rupture of the line at the customer’s side.

In India, excess flow check valves are widely used in residential complexes where there is a huge requirement for LPG supply to all the residences. Excess flow check valve manufacturers in India such as AEPL, study the layout of these housing complexes and their service lines. Based on their study, standard or custom-engineered EFVs are installed in the service lines for a controlled and safer supply of piped gas from the main gas line to residents.

Do you think EFV is an effective way for supply of petrochemical gases? Share your thoughts on the usage of EFVs.

A Comprehensive Guide to Excess Flow Check Valves and its Features

Excess Flow valves also referred to as velocity check or seismic valves, are created to shut down immediately after a sudden surge of flow. An excess flow valve is basically an in-line valve via which liquid or pressurized gas flows in both the directions. They shut down after excessive discharge of vapor or liquid caused due to the breaking of the pipe system. After the flow rate has exceeded the setting of the valve, it continues to remain closed till the time system pressure becomes stable. In case the flow doesn’t exceed, the valve’s setting won’t close.

A leading number of excess flow check valve manufacturers are manufacturing innovative and affordable valves, which are available in different configurations, flow rates and sizes, based on the vessel’s construction and the desired flow rate that are crucial for completing the process. Read on to find out more about excess flow check valves and their unique features.

Excess flow check valves

The excess flow check valves can be easily purchased in numerous pressure materials, classes, end connections and flange designs. These valves undergo stringent check in a certified flow laboratory for performance and durability. The excess flow valve is basically a spring loaded check valve that closes only after flow of vapor or liquid via the valve produces sufficient force or flow for overcoming the strength of the spring that helps in keeping it open. Each of these valves is available in multiple sizes as well as flow rates based on the reason for which they’re being used. It is important to determine the purpose for which the valve will be used prior to installing it. The excess flow valves are utilized for different fluids as well as processes including excess flow check valve for lpg gas, anhydrous ammonia, butane, nitrogen air, anhydrous chlorine, water etc.

They allow vapor or liquid to flow in different directions. The flow is usually controlled in one specific direction as each of the valves come with an arrow. Hence, when the flow in the desired direction surpasses the already determined flow rate, the excess flow check valve closes automatically.

The disk of the valve remains in an open position with the help of a spring. After the vapor or liquid flow results in a drop in the pressure across the disc of the valve that is exceeding the present flow rate, the disk of the valve closes against the valve’s opening to hinder the flow of the liquid or vapor. This valve disk remains closed till the time the pressure between both the downstream and upstream sides of the flow check valve equalizes. After the pressure equalizes, the flow check valve will open automatically. As a result, when the line’s broken or ruptured, the pressure towards downstream won’t equalize and the valve won’t open till the time the line’s been repaired.

To sum up, excess flow check valves are ideal for handling fluid components for oil and gas, chemical as well as petrochemical industries as well as water blast organizations.

What is the Purpose of a Safety Relief Valve?

Safety relief valves or the pressure relief valves are the devices that are used in almost every industry to give the machinery an ultimate security from getting damaged due to over-pressurization. The most efficient safety relief valve manufactures design the valves in order to cater the diversified needs of the different industries. They thrive to survive in the market by designing the tailored valves that exactly meet the specific demand of the clients.

Importance of the Safety Relief Valves

The safety relief valves are a very important aspect of an industry, as it offers protection to life as well as property. When a system operates, an amount of pressure builds in it as a result of multiple functions. Though the device depletes the developed pressure, the pressure relief valve gives an overall protection to the machinery from any catastrophic incident by opening an outlet. This releases the excessive pressure that makes the ambiance inside the system favorable for any operation. More than attaching a valve with a device, it is important to check the reliability and work ability to ensure its operation at the time of emergency.

The Need of the Safety Relief Valves

The safety relief valves are attached to the systems that have pressure as an important component. The valve starts operating when the pressure exceeds the set limit. The following are the reasons which contribute to the increase in pressure:

• Faulty cooling system, which results in the expansion of liquid or gas.
• Electrical power failure.
• Increase in compressed air.
• Fire in the plant.
• During the initiation of the industry.

The valves should be designed in a manner to meet the industrial needs that not only saves the system from any damage, but also ensures longevity. The valves may not function properly if they are not maintained, installed or correctly sized, leading to destruction.

Types of Safety Relief Valves

There are two types of safety relief valves available, which have different exhausting principle. One is the Pop action safety relief valve, which opens an outlet immediately after the pressure inside the system reaches the set limit, lowering the pressure. Another is the angle type discharge safety relief valve that gradually exhausts the pressure in order to make the built-in pressure normal. This also helps in regulating the flow of the liquid or gas along with the safety function.

Excess Flow Check Valve

The excess flow check valve makes sure the system is able to support a huge quantity of liquid or gas flow with a minimum pressure loss. This valve can be utilized in any position and is one of the best options for installing in lines. It functions efficiently in gas as well as in liquid and can be modified based on the client’s demands. It starts operating automatically when the pressure reaches the set limit or there is a fire.

Conclusion

The safety relief valve goes through various levels of checking and testing to ensure the accurate work ability at the time of emergency. The tough and tolerant material is used to manufacture the valves that are sufficient to withstand the extreme conditions of the operations. Therefore, if all the elements are used accurately in the manufacturing process, then the resultant valve will be sufficient to meet the extreme conditions.

Types of Pressure Relief Valves

Relief valves, which are also known as pressure relief valves are the unique type of safety valves that are used to bring the pressure of a system under control. Pressure is a very important aspect of any system which also has the capacity to upset the entire operation if not kept under proper control. The working principle of the pressure relief valves is to release the excessive pressure from a system by releasing the pressurized fluid through an auxiliary passage. There are numerous pressure relief valve manufactures in the market, but only a few of them meet the expected industrial standard.

Importance of the Pressure Relief Valves

An industry is built up of numerous machinery pieces that consist of diversified functions. It is very important to keep those in perfect working order to get the most out of it. Temperature and pressure are the criteria that drive the output in an effective way. Hence, it becomes essential to get in touch with one of the best valve manufacturers, who will supply the most efficient valve to protect the system from any harm. However, it is also essential to select the right kind of pressure relief valve in order to enjoy the proper functionality. Let’s have a look at the types of pressure relief valves available:

1. Safety Relief Valves

These valves keep the machines safe by releasing the excess pressure from it either immediately or gradually, depending on the requirement. There are two types of valves available with the safety relief valve manufacturers:

• Safety or pop-off valve – open an outlet completely when the set pressure exceeds, resulting in the excretion of the excess pressure through an additional valve.
• Angle type discharge valve – releases the pressure gradually when the pressure exceeds the set limit. Along with controlling the pressure, it is also effective in managing the flow in the system.

2. Excess Flow Check Valves

It is a spring impregnated check valve that either opens or closes depending on the velocity of the fluid flowing through it. The excess flow check valve manufacturers mainly design valves that are used in LPG, NH3, pipelines, road tankers and Propane storage tanks, which demand huge flow capacity valve with negligible pressure drop. It is suitable for both the liquid as well as gas and protects the system by automatically shutting down the process.

3. Ball Valves

It is a spherical closure device that is used to control the flow in a system. The competent ball valve manufacturers design the valves in such way that meets the industry standard in an efficient way. It uses the mechanism of rotational motion to shut or open the flow of liquid or gas. This type of valve doesn’t demand huge maintenance cost and is compact in size, making it easier to handle. This type of valve is preferred by all due to its low torque and quick tight sealing.

Conclusion

All the pressure relief valves have different mechanisms and are used in different fields to meet the diversified needs. Hence, one must consider the quality of the valves provided by the manufacturers to get the best deal on the market.