Thanks for your help, I analize all of your answers. Unoftunately 1" selenoid valves are expensive and sprinkler valves are impossible to use for my applciation because I need to close and open the valve with or without pressure across the valve, sprinkle valves usually need a pressure in the system to open and close and in my project the pressure is very low.
I resolve this problem with the ball valve and a servo, I use a cheap 11 Kg-cm servo and until now is doing just fine. Probably I will need to change it in the future for another of better quality or stronger.
Thanks again!