# How fast does a hydraulic machine work?

robhlee
How fast does a hydraulic machine work? The model i am thinking of is a simple two-sided setup, where the surface areas of the two platforms are different and a tube connects them. In terms of movement of the two platforms, how fast can the machine work. I am just looking for an approximation, like can it be instantaneous or are hydraulic machines usually very slow-moving?
Also, would the diameter of the tube connecting them (smaller than the diameter/surface area of either platform) affect the speed of the mechanism?

## Answers and Replies

Gold Member
Robhlee, when I suggested that you have this moved to Engineering, I didn't mean for you to repost it. A mentor can relocate the complete thread for you.

In theory, the speed limiting factor of any hydraulic system is going to be the flow rate of the fluid. If you want a cylinder to extend at a certain rate, you need to have a flow rate that will fill that cylinder's volume as it is extending that fast. So to answer your question about the tube size having an effect, I would say that it depends. You need to create enough pressure in the system to provide the flow you need. If you have a very small tube, you need a pretty high pressure.

Your other questions are pretty vague. They are difficult, if not impossible to answer. Can you be more precise with what you want to know?

robhlee
how can i show a picture on this forum (w/o creating a new topic) ?