valve size & type

1-There is a valve spool for the X-Ray guage measurement in our rolling mill system,now Pressure drop across the valve is 2 bar, the cooling water return line outlet water is got to have the back pressure of 1/2 a bar at the outlet, I have selected a 1/2 inch Globe valve is that OK?

2- Supply water of 7 bar going to the same valve spool system, we need a valve type & size to provide inlet supply water to valve spool as flow of 0.6M3/Hr and pressure of 2.5 bar. I have calculated Kv which has come out to 0.282, now I have different tables but not showing the valve size/type, could you please show me the calculation. water is plant water @ 25 degree C , you can ignore the tempreture.

Cheers

AT