The swing check valve is a valve with a disc-shaped disc that rotates around the shaft of the valve seat channel. Its channel is streamlined, which allows the flow resistance to be smaller compared to the lift check valve. This type of valve is suitable for large-diameter situations where the flow rate is low and changes in flow are infrequent. However, it is not ideal for pulsating flow, and its sealing performance is not as good as the lifting type. The swing check valve can be categorized into three types: single-lobe, double-lobe, and multi-lobe. The distinction between these forms arises from the valve's diameter.
The lifting check valve is a type of check valve where the disc moves vertically along the centerline of the valve body. It is typically used in horizontal pipelines and is suitable for high-pressure and small-diameter applications, where the disc can be made of balls. The valve body of the lifting check valve has a similar shape to the globe valve and can be used interchangeably with it. However, this design results in a higher fluid resistance coefficient.
The structure of the lifting check valve resembles that of the globe valve, with the valve body and disc being identical. The upper part of the valve disc and the lower part of the valve cover feature guide sleeves, allowing the valve disc to move freely up and down within the valve guide. When the medium flows downstream, the thrust of the medium opens the valve disc, causing it to drop vertically onto the valve seat, effectively preventing the reverse flow of the medium.
There are two variations of the lifting check valve. The straight-through type has its medium inlet and outlet channels perpendicular to the valve seat channel. On the other hand, the vertical lift check valve has the same direction for both the medium inlet and outlet channels as the valve seat channel. Due to this difference, the vertical lift check valve offers lower flow resistance compared to the straight-through type.
The disc check valve is a type of check valve that features a rotating disc around a pin shaft located in the valve seat. Although it has a relatively simple design, this type of valve is only suitable for installation on a horizontal pipeline. Moreover, the sealing performance of the disc check valve is not as efficient as that of other types of valves.
3. The pipeline check valve is a modern innovation in valve design, featuring a sliding valve disc along the centerline of the valve body. This compact and lightweight valve has excellent processing technology, making it a promising development in the field of check valves. However, it is important to note that compared to the swing check valve, the pipeline check valve has a slightly higher fluid resistance coefficient. Despite this, its unique design and technological advancements make it an attractive choice for various applications.
The compression check valve is an essential component used in boiler systems to regulate the flow of boiler feed water and steam. It combines the functionalities of a lift check valve, as well as a globe valve or angle valve. This versatile valve ensures efficient and reliable performance for the overall operation of the boiler system. Whether it's providing a secure cut-off for steam or maintaining optimum water flow, the compression check valve plays a crucial role in ensuring the smooth and safe functioning of the boiler system.
Furthermore, it is important to note that certain check valves should not be used for pump outlet installation. This includes foot valves, spring-type valves, Y-type valves, and so on. It is crucial to consider these limitations and choose the appropriate check valve for your specific application.