U.S. Plastic Corporation Nibco Chemtrol True Union Ball Check Valves 18297

Not spring loaded but the design insures free movement of the ball. Ball supported by a system of guide ribs to give full flow with minimum turbulence and chatter. Union connections for easy access to valve components. Requires only inches of head pressure to seal and open. All plastic construction which eliminates corrosion. FKM seals, O-rings and ball seats. Equally effective in checking backflow from head pressure on the discharge or suction side of pump. Seating head 1/2" thru 3/4" 6-7 psi; 1" thru 2" 4-5 psi; 3" size 3-4 psi. 2 pound positive back pressure. Both types are NSF listed. PVC - 140 F. CPVC 210 F. Screen assemblies for conversion of true union ball check valve to foot valve are sold separately.