INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Jobs

HYDRAULIC PUMP MANIFOLD ISSUE TO UNDERSTAND

HYDRAULIC PUMP MANIFOLD ISSUE TO UNDERSTAND

(OP)
Hi Guys,

First of all i'm sorry i don't have complete information of this old system. Please see my attachment for overall hydraulic schematic (you can download the pdf too).


I have a problem to understand how the system function. I understand how the solenoid valve (SOV 7 and 8) operated but on the manifold, i cannot figure out how it is operated.
From my view, when the SOV is energized, it will direct the oil from P to A and straight to the manifold.

From here i'm not sure, does it operated the valve (34) thus turn on the pump? at the same time it go to pilot (43) and energize the internal valve?

What is valve 34? Is it just a connection to point 'x' in the hydraulic motor (pump) schematic as i found the model is Rextroth AA6VM55HD2/63W-VSD510A.


What is valve in red circle?


Can someone help me explain how these two banks work please.

R.Efendy

RE: HYDRAULIC PUMP MANIFOLD ISSUE TO UNDERSTAND

The valve (34) is the motor controller. The red circled valve is a pilot operated shut off valve that isolates the motor from the pump pressure.

The shut off valve is piloted open when the solenoid valve (directional control valve) is operated. At this point as pressure signal, regulated by a proportional pressure reducing valve in the manifold, is fed to the valve to open it to start the motor turning. The speed of the motor is controlled by the same pilot signal. This is fed to the motor 'X' port as you say. The proportional pressure reducer is used to vary the pressure and therefore change the displacement of the motor (speed).

RE: HYDRAULIC PUMP MANIFOLD ISSUE TO UNDERSTAND

(OP)
So the valve in red circle is proportional pressure reducing valve?
That means only when the X port is open then only the flow will go through the valve in the manifold and turn the motor?
Is that correct?

R.Efendy

RE: HYDRAULIC PUMP MANIFOLD ISSUE TO UNDERSTAND

I have edited my post. I made an error. Sorry to confuse you.

The proportional pressure reducer cannot be seen on the images above. You need to open the PDF to see it.

It's in the main manifold, higher up in the drawing. It's under the directional control valve.

The pressure to the X port also goes to the shut off valve. The pressure opens the shut off valve and controls the motor speed. The motor will not turn unless there is pressure at the X port.

RE: HYDRAULIC PUMP MANIFOLD ISSUE TO UNDERSTAND

(OP)
Now i wonder if these two valves (in red) are actually the same valves? What do you think?






R.Efendy

RE: HYDRAULIC PUMP MANIFOLD ISSUE TO UNDERSTAND

Yes, they are the same valve. Well almost...

The Bosch Rexroth is the fully detailed version.

I think that the person that drew the schematic on the PDF was short of room on the drawing sheet, so they drew a simplified version.

They are both displacement controllers for the motor, the end result is same.

Item 34 is the controller, the part that you have circled on the Rexroth version.

The part you have circled on your schematic is the control piston that moves the motor to control the displacement.

RE: HYDRAULIC PUMP MANIFOLD ISSUE TO UNDERSTAND

(OP)
I think that's satisfied me now. Thanks HPost! Really appreciate your view.

R.Efendy

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources

eBook: Metal 3D Printing
Metal can provide strength like no other material can and, throughout our history on Earth, humans have learned to harness metals for ever greater specialized applications, from radiation shielding on spacecraft to conductive components on circuits. Download Now

Close Box

Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

Register now while it's still free!

Already a member? Close this window and log in.

Join Us             Close