C.R.I. energy efficient frictionless Foot Valves and Reflux Valves are basically swing type Non Return Valves. Foot Valves are available in screwed type construction and Reflux Valves have threaded portions at both the ends. They are specially designed to give an unrestricted smooth flow of water and thus to reduce the frictional losses to a minimum. The C.R.I. frictionless Foot Valve has 'K' value less than 0.8 and 'K' value for Reflux Valves are less than 0.5. Thereby it reduces additional load on prime mover and also gives more discharge.
Foot Valve is placed at the lower end of the suction pipe of a centrifugal end suction pumpset to retain water in the pumpset casing and suction pipe to keep the pumpsets always in priming condition. Reflux and Non Return Valves are fitted generally in the delivery pipeline to avoid water hammer, up thrust and backspin effects in the pumping system. These can also be used anywhere in the suction line of which the bottom end is entered into a bore pipe or tube well. The pressure withstanding capacity of Reflux Valve and Non Return Valve are 1 bar and 15 bar respectively