This process will continue until the flow is large enough such that the increased dynamic differential pressure greatly exceeds the closing force therefore keeping the valve open.

Check valve boilerinstallation

To convert gallons per minute to cubic feet per second, multiply the GPM by the conversion factor (0.133681) and then divide by 60.

High pressure steam Non ReturnValve

When the opening force outbalances the closing force, the valve mechanism opens (opening pressure). The necessary opening pressure depends on the spring tension or the mass of the counterweight, the position of installation, and the size of the check valve.

This is produced by the impact of the valve disc, cone, or flap repeatedly closing on the check valve seat. In some instances, instead of generating a clatter, a high-frequency humming tone is heard.

Check valve boilertypes

Depending on the flow rate, the check valve opens either completely or only partially. During partial opening, for example, at a reduced flow rate, clatter may occur.

When the pressure upstream of the check valve drops, and the closing force once again outbalances the opening force, the valve begins to close.

A check valve provided with a spring or counterweight begins to open when a certain static differential pressure (upstream pressure minus the downstream pressure acting on the valve) across the valve has been reached.

Flowcheck valve boiler

Check valve boilerdiagram

In such cases, the valve is temporarily oversized only during certain operating phases. It may be possible to solve the noise problem by reducing the closing force by selecting a check valve with a weaker spring or a reduced counterweight option.

The possibility of utilizing a smaller, nominally sized check valve is not feasible if the ensuing pressure drop at full load is not acceptable for the application.

An incessant noise is a sure sign that too large of a check valve was selected; the valve was not chosen optimally to match the requirements of the application.

This produces an opening force (pressure differential x cross-sectional area of valve), acting against the closing force.

Gallons per minute (GPM) is a unit of flow rate that indicates the number of gallons of liquid that flow out of a system in one minute. It is commonly used in the United States to measure the flow rate of water in plumbing systems, irrigation systems, and other fluid transport systems.

Cubic feet per second (CFS) is a unit of flow rate that indicates the volume of fluid passing a point in a system per second. It is commonly used in hydrology, river engineering, and environmental engineering to measure the flow of water in rivers, streams, and other open channels.