Losing hydraulic chuck pressure
Close
Login to Your Account
Results 1 to 6 of 6
  1. #1
    Join Date
    Jan 2019
    Country
    UNITED STATES
    State/Province
    Michigan
    Posts
    1
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    0

    Default Losing hydraulic chuck pressure

    Mazak QTN100 consistently losing chuck pressure while engaged. Starts at 350 and will slide under 150 within 20 minutes. When its not engaged it pops back to the set 350. Could this be an actuator issue? Any thoughts?

  2. #2
    Join Date
    Aug 2018
    Country
    AUSTRALIA
    Posts
    288
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    39

    Default

    what pressure gauge are you talking about.. one for CHUCK ? what about pressure indicator on systems hydraulic pump???
    do you have this safety valve? that can be leaking OR main hydraulic valve isnt holding pressure, lets say solid state relay failing after a period of time. Open you hydraulic drawing in your parts manual and have a look how oil is going towards CHUCK ACTUATOR
    Attached Thumbnails Attached Thumbnails 1.jpg  

  3. #3
    Join Date
    Feb 2015
    Country
    SWEDEN
    Posts
    625
    Post Thanks / Like
    Likes (Given)
    107
    Likes (Received)
    296

    Default

    I would guess internal leakage in the actuator.

  4. Likes mc3608 liked this post
  5. #4
    Join Date
    Aug 2018
    Country
    AUSTRALIA
    Posts
    288
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    39

    Default

    Quote Originally Posted by benganboll View Post
    I would guess internal leakage in the actuator.
    it will be a simple piston configuration. if it leaks unclamp, them it will leak CLAMP. too easy forus

  6. #5
    Join Date
    Feb 2015
    Country
    SWEDEN
    Posts
    625
    Post Thanks / Like
    Likes (Given)
    107
    Likes (Received)
    296

    Default

    Quote Originally Posted by noname777 View Post
    if it leaks unclamp, them it will leak CLAMP. too easy forus
    I will not agree.
    My excavator had no force in one direction but full force in the other direction on one actuator.
    It was the sealing around the piston that was broken and fliped out of position in one direction and sliped back in in the other direction.

    It is easy to test, disconnect actuator pipes/hoses and plug them, if you then have full pressure when you clamp unclamp the problem is at the actuator.

  7. #6
    Join Date
    Aug 2018
    Country
    AUSTRALIA
    Posts
    288
    Post Thanks / Like
    Likes (Given)
    0
    Likes (Received)
    39

    Default

    Quote Originally Posted by benganboll View Post
    I will not agree.
    My excavator had no force in one direction but full force in the other direction on one actuator.
    It was the sealing around the piston that was broken and fliped out of position in one direction and sliped back in in the other direction.

    It is easy to test, disconnect actuator pipes/hoses and plug them, if you then have full pressure when you clamp unclamp the problem is at the actuator.
    the guy says:

    -When its not engaged it pops back to the set 350

    I would assume actuator is OK, as it should be simple hydraulic o-ring,I might be wrong here.



    the other thing is that configuration has two check valves (if pump stops they will still hold the job), and they can be lifted with pilot pressure. What if one cannot be lifted properly with pilot pressure? One for UNCLAMP. When you clamp, oil goes into right side of cylinder and cannot escape from left side but....through , pressure safety relief valve (on the top) it will drain itself into right side, allowing clamping.

    By now chuck is closed. All is ok. After a certain period of time, internal leak will push oil into left part of cylinder ( on attached picture) where bigger area of piston will push it into left( unclamping) .

    That is how theoretically the problem can be explained. But what is inside CYLINDER ? I dont have this drawing at this moment.


Tags for this Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •