Hydraulics Proportional Valve

I don't think so. The greater pressure should result in greater flow through the valve, thereby increasing the pressure drop.

differential equation Bernoulli?

The capacity rating is usually at the working pressure rating. Test pressure is usually 3 to 4 times working pressure. Pressure drop has to due with porting and fluid flow. Which would change with the application(the load on the driven device).

If I have only a fixed 80 bar oil supply. Then how do you put 315 bar on it!

It will be different. For detailed information on the valve's performance, please contact the local distributor directly.

Your question makes little sense, your talking about a proportioning valve, so your pressure drop is going to be proportional to the valve position.

Little sense?

"Please do not relate or assume load sensor..or some thing else."

That means no sense.

I mean, when pressure required at end point is less there will be no sensor to initiate the system to supply higher pressure of oil to pressure port of proportional valve. It just fixed pressure 80 bar supply to pressure port of proportional valve.

Now I hope you got it!

Not yet.

If the supply is 315 bar and the downstream pressure is fixed, if the valve position is different then where does the remaining pressure drop go to sustain the same flow rate?

315bar is the tested pressure for proportional valve by manufacturer. But it is used input pressure of 80bar which is fixed.

The pressure out put from proportional valve is used to operate in closing the component the system.

my question is if this 80 bar is used will have the pressure drop of 20bar, which is same as for 315bar (tested pressure) of proportional valve.

This reply is for Anon #1, being none of us are there with you and can not see how you have this thing plumbed, why don't you simply put a pressure gauge down stream of your proportional valve, operate this system and see for yourself what the actual pressure drops are for the valve or what ever your going to operate, motors, rams or what ever

Oh yeah, how did you did come with a handle of "hydraulic14" and yet ask a question like in your OP?

Just wonder'n