Multiple check valve

In general calculation methods do not consider the effect produced by the non return valve. Nevertheless they are valid methods if the valve of retention behaves in a ideally perfect way.
An ideal non return valve will close when the speed of the fluid in every point of the closing surface is exactly zero.
In our valve the displacement of the closing element is 1 cm and it does not depend on the diameter of the pipe.
This displacement and the fact that they are multiple independent closings make the behavior of this valve practically equal to the ideal one.
The conclusion is that in facilities with our type of valve the water hammer calculations are valid.
The measurements that we have realized in many facilities with our valve confirm that the measured pressure is always a minor to the calculated one.

POLANCO valves