Wafer Check Valves
Both lift and swing check valves tend to be bulky which limits their size and makes them costly. To overcome this, wafer check valves have been developed. By definition wafer check valves are those that are designed to fit between a set of flanges. This broad definition covers a variety of different designs, including disc check valves and wafer versions of swing or split disc check valves.
- The check valve is used to prevent boiler water being forced back along the feedline into the storage tank when the feedpump stops running.
- Other than with steam traps discharging to atmosphere, check valves should always be inserted after a steam trap to prevent back flow of condensate flooding the steam space.
- Check valves can be used as vacuum breakers, by fitting them in reverse.