Originally Posted by ducas99
I just downloaded a pretty cool phone app for hydraulics you enter in the ram specs
Piston diameter - 3"
Rod - 1.75 ( 1 3/4")
Stroke - 24"
Pressure - 3000psi
Time can ether enter stroke in or out I put 10 secs out
And it spits out
Oil flow rate = 4.41 gpm
Force 21200 lbs
And heap of other info so hope I can now find some parts that will match and go at the speed I want just have to search for a pump with working flow rate of around 4.5gpm
10 secs is pretty quick tho and I won't be bending that big a pipe (1.5" x .120) so could maybe go a smaller bore size. Still have to do more research tho.
4.5gpm at 3,000psi is going to take about 7.9hp (5.9kw). I'm guessing you will not have that big of a motor available (unless you plan to run it off petrol).
If you are designing for a 1hp (0.75kw) motor, you can do 3,000psi max at 0.57gpm, so a more typical pump selection would be 0.5gpm for a 1hp motor. Remember your max bending speed, when optimizing all the geometry and hydraulic selection, is purely a function of the max tube capacity bending torque and the power of your motor.
One of these days I need to find a few hours to write up a primer on bender hydraulics with some of the math and geometry to help folks out with ram, pump, motor/drive, and valve selection.
Are you guys thinking of using that type of end of stroke valve as an auto stop? I don't think you'll get a very repeatable stop location with something like that because the transition to open is not abrupt. Better to have an electric switch (or better yet, encoder-based control) and solenoid valve to stop the cycle.