I forgot to mention - the wafer checks are NIBCO Class 125 Iron Body Silent Check Valves with renewable seat and disc. They are rated at 200 psi, not 175. The seat is Buna-N bonded to bronze.
@Littleinch, et.al.
These wafer checks are install on the discharge side of three fire pumps supplying our sitewide fire protection systems. The pumps are rated at 2500 gpm @ 130 psi. The check valves are UL Listed / FM Approved for this application and rated for 175 psi working pressure...
I am working on a start-up project for which I need failure rate data for wafer check valves. Specifically failure to close. My application involves 10" wafer checks installed in a water system with a working pressure less than 175 psi. Please post experience and/or links to resources. Thanks in...