Another hydraulic question???? system buzzing..

[Kentucky]

We just replaced the pump on an uncle al's press. Press seems to be working fine but now its is making a loud buzzing when the actuator is first pulled down though when you go to full up or downward stroke it goes away..Also when your holding the pedal, the actuator is held in place of course this makes the ram stay were you want it..It also has that loud buzzing then too but again goes away when you go up or down..Sounds normal when just running..The pump seems to be working fine, no vibration anywhere..Lines and hoses clear.. Any ideas?????? i thought it might be air cavatation but im not sure how thier could be air in the lines because when the fluid is cycled back through its dumped int he tank from the top..Its driving me crazy not being able to figure it out...

 

[Kentucky]

Im starting to think maybe its the relief valve chattering but Im not sure why?

 

[Kevin Powers]

My iron workers at work change pitch and get real loud when you hit the stops. It's the bypass so the machine doesn't self destruct, not sure if this is your problem but it sounds like it to me.

 

[Navin_R_Johnson]

Top tank can still get air in the lines, don't rule it out. Did you ever pull apart to see why the last pump failed? If it were from cavitation you might look closer at what may have or is causing it.

Can you feel vibration in any of the lines?
Do you have a schematic for the pneumatics?

Then again, describing a sound on the nets is pretty tough. How loud is "loud"? You might just be fine?

 

[12345678910]

The way you describe it, it sounds like the relief valve.
Do you have a pressure reducing valve ?
do you see any movement in the hoses ?



I'd put a stethoscope on it if you really want to know


Find a wooden broom stick
Just the handle.

Put the rounded end in your ear, up against the cartilage behind the hole and hands off.

Then put the other end up against various parts of the press

It will be perfectly clear which part is the loudest one.