For check valves, swing checks and wafer checks are actually similar in many ways. Both serve to block back flow from occurring in a pipe line. Both use a swinging disc to block and allow flow in one direction. The differences in the two valve may seem obvious when you use them.
Wafer dual plate check valve

Swing check valve

First , the design and function are different

Wafer check valves get their name from their wafer thin design. These valves are sleek and made to fit in tight spaces between two flanges. There are no controls on this valve. The main component of the valve is a swinging disc in the center that opens in one direction and closes if liquids flow back the other direction.

Swing check valves also uses a swinging disc to allow or block flow. The difference between the two is in the body design. Swing check valves are not designed for extremely tight spaces like the wafer check. They have molded bodies around the area where the disc opens up. This is the most important difference between the two types of valve.

Second,different application fields for 2 types of check valve.

Swing check valves on the other hand, have a molded body that creates room for the disc to swing open fully, thus allowing full flow. As you can imagine, this is immensely important if your application requires full flow. For this reason, we recommend wafer check valves for applications where flow is not an issue, and swing check valves when a full port valve is required.