Single check valve and double-plate check valve in a number of aspects there are significant differences, the following six paragraphs for detailed description:

First, the composition of the structure

Single flap check valve is mainly composed of a valve flap, the valve flap is usually made of elastic or metal materials, fixed in the valve cover. The double-plate check valve, as its name suggests, consists of two valve plates (or double flaps), there is usually a certain gap between the two flaps, fixed on the valve body.

Second, the working principle

The working principle of single flap check valve depends on the elastic deformation of the valve flap. When the fluid is flowing in the positive direction, the valve is flushed open, allowing the fluid to pass; when the fluid flows in the opposite direction, the valve is impacted by the fluid and squeeze the sealing surface, to achieve closure. Double plate check valve through the fluid pressure difference to realize the opening and closing. Forward flow, the flap automatically open; reverse flow, the flap in the reverse fluid pressure closure, to prevent backflow.

Third, application Scenario

Single-plate check valve is suitable for low-speed, low-pressure and pure media pipeline system, commonly used in health, environmental protection and food industry and other occasions. While the double plate check valve is more suitable for pipelines with high speed, high pressure and dirty medium, such as chemical, petroleum, metallurgy and other industries, because of its stronger sealing performance and pressure resistance.

Fourth, the performance characteristics

Single valve check valve structure is simple, easy to maintain, but the closure is not thorough enough, there is a possibility of leakage, and in the high-speed fluid or large flow rate is not closed quickly enough. Double-plate check valve is closed more thoroughly to prevent leakage effect is remarkable, and in the high-speed fluid conditions close quickly, will not affect the pipeline system operating efficiency.

Five, installation and maintenance

Both need to pay attention to the direction of media flow on the installation to ensure that the check valve works properly. However, the double plate check valve due to its relatively complex structure, installation and maintenance may require more attention to ensure that its flap can rotate smoothly.

To summarize, single check valve and double plate check valve are different in structure, working principle, application scenario, performance characteristics, installation and maintenance, and cost, the user should make a reasonable choice according to the actual needs.