Selecting a Center Guided Check Valve

It is very common for a system that manages a piping system, especially a system expected to perform process control and media flow manipulation tasks, to require the use of various types of valves to successfully meet these expectations. A center guided check valve is one type of valve that can be utilized to help a system control the flow of process media.

A center guided check valve is specifically designed to assist a system in controlling where a liquid or gas is flowing within a system. This type of two-port valve allows media to enter through one opening and leave through the second opening when the valve is in the open position. A center guided check valve can close after the media has passed through, and this action is often initiated to ensure that the media already on the other side of the valve does not return to its previous location. In systems that provide circulation, it is especially critical that the only process media released into the circulation path are the medias that have already been filtered and refined, and not medias that have been contaminated in any way. The act of flowing backwards into previously traveled parts of the system, and mingling with media and locations that have not experienced the same filtering and prepping processes, could result in less successful circulation operations.

A center guided check valve is generally shorter than other types of valves, and possesses a lower cracking pressure. The cracking pressure is the point of pressure which causes the valve to close, thus preventing any additional backflow from occurring after the gas or liquid has successfully traveled to a point in the pipe system beyond the valve location. This pressure is read as a pressure drop, since the pressure is higher and consistent when there is a steady flow of media that needs to pass through the valve. Additionally, when there is a steady flow of media passing through, the flow that comes after the early part of the flow stream is exerting pressure in the appropriate direction to keep the media from flowing backwards. It is when that flow slows down and the pressure drops that backflow becomes a possible issue. In these instances, a spring will release the center guided check valve to closed position, and none of the fluid will be able to access the previously traveled section of pipe. When enough volume of process media is flowing in the desirable direction through a pipeline, the pressure is great enough that the spring is compressed and the valve is held open through that flow pressure.

There are many different materials available for a company to consider when placing an order for a center guided check valve. These materials include carbon steel, stainless steel, cast iron, and cast alloys. Each particular material may respond and influence the fluid flowing through a system, so the exact components of all parts of a system need to be contemplated before a final purchase is made. Better planning before purchase and implementation will yield better results.