Proportional hydraulic valve : performance limit

[aand74]

We have a proportional valve where we suspect that we may be at the performance limit.
With the performance limit, I mean what I see in a curve of flow in function of valve pressure differential. So, big pressure difference at the valve combined with high flow.
What are typical results when a proportional valve is at this performance limit?

 

[V0N_hydro]

the proportional valve is limiting the rate of change of position of the actuator. The pressure drop is across the valve instead of at the actuator.

 

[seth350]

Tell the production people they just won't be able to leave early on Fridays. J/K...kinda

Seriously though, if this is on a machine that has been "ok" so far. When you start to question if you are at a critical mass with component limits, typically something else a lot simpler is wrong.

Not always, but typically.

Here's an easy check.
1) Record nominal flow rate of pump
2) Record volume characteristics of actuator. Cylinder area, etc.
3) Evaluate what the speed of the actuator SHOULD be according to your findings.
4) Measure actual speed of actuator

If substantial difference, measure actual pump flow rate and case drain too if you have access to it. High flow rate on case drain is the smoking gun for a toe up pump.

What brand servo valve are you using and what flavor pumps and actuators?