Page 1 of 3 123 LastLast
Results 1 to 10 of 30
  1. #1
    Veteran Member Jay4200's Avatar
    Join Date
    Nov 2005
    Posts
    1,716
    Location
    Hudson/Weare, NH
    Tractor
    L4200GST w/ LA680 & BX2200D w/ LA211

    Default Regenerative circuit?

    What exactly is a regenerative hydraulic circuit? Is it when two SA pistons have a single 2-way control instead of using a single DA piston? How do they work n' how are they hooked up?

    Just attempting to educate myself...

    Thanks - JayC

  2. #2
    Veteran Member
    Join Date
    Apr 2009
    Posts
    1,023
    Location
    Port Angeles WA

    Default Re: Regenerative circuit?

    Quote Originally Posted by Jay4200 View Post
    What exactly is a regenerative hydraulic circuit? Is it when two SA pistons have a single 2-way control instead of using a single DA piston? How do they work n' how are they hooked up?

    Just attempting to educate myself...

    Thanks - JayC
    Simplified...it is a single rod double action cylinder, that in extend motion get pump pressure on both sides of the piston....the area differential makes net force to extend, but at a speed as a cylinder with the diameter of the actual piston rod.....


    There are way more ways to make regen circuits, even on retract....read here...

  3. #3
    Veteran Member
    Join Date
    Apr 2009
    Posts
    1,023
    Location
    Port Angeles WA

    Default Re: Regenerative circuit?

    Regen fills several purposes....

    >anti cavitation prevention, helps pump flow to refill capped side...
    >quick unload of gravity forced loads, like FEL bucket...
    >quick advancement of a hydraulic press cylinder...

    There are valves that senses presure and "switch gear" when pressure increases....see SUN Hydraulics

  4. #4
    Advertiser kennyd's Avatar
    Join Date
    Jul 2003
    Posts
    11,697
    Location
    Westminster, MD
    Tractor
    John Deere 4110, 455

    Default Re: Regenerative circuit?

    Regen is a "feature" of most modern FEL (Front End Loader) valves, it's on the Dump (joystick far right) circuit, and is also referred to as "Fast Dump". The reason it is nice to have is that without it, the weight of a filled bucket can actually "pull" the bucket down faster then the fluid can enter the other side of the cylinder, this will create a air pocket and give the bucket a "floppy" feeling until the joystick is held in the dump mode a few seconds to refill the cylinder pushing the air past the seals. So we add "regen" or "regenerative" function to the valve.

    Regen solves this problem by actually filling both sides of the cylinder at the same time with hydraulic fluid. But how will that work you might ask? Well, because there is more volume on the side of the cylinder that extends it since the rod is taking up space in the other side, it "overpowers" the rod side and lets the cylinder extend-thereby dumping the bucket. So since now both sides of the cylinder are "pressurized", the air pocket can not develop, eliminating the "floppy" bucket syndrome. One other added bonus is that the bucket actually dumps faster due to the higher flow rate required to do all this, that's why it's referred to as "fast dump" sometimes.

    So, now you may be asking "This is cool and all that, but why do I need to know about it??" The answer to that is simple, if you ever try to run a snow plow with two SA (single acting) cylinders, or a cylinder that drives a chute rotator on a snowblower you will soon find out that they won't work if you push the joystick to far right in the regen mode. The plow won't work because since both lines are pressurized-both cylinders will be trying to extend at the same time binding everything up. The rotator won't work because there is no weight pushing the cylinder closed like there is on the loader.
    KennyD
    www.boltonhooks.com



    Bolt On Grab Hooks, Weld On Grab Hooks, Specialty Chain Accessories, Specialty Hydraulic Components.

    Simple JDParts Tutorial HERE

    Visit our YouTube Channel

  5. #5
    Veteran Member
    Join Date
    Apr 2009
    Posts
    1,023
    Location
    Port Angeles WA

    Default Re: Regenerative circuit?

    "....a single rod double action cylinder..."

  6. #6
    Elite Member
    Join Date
    Jan 2010
    Posts
    2,577
    Location
    Northern, IL
    Tractor
    Branson 2400H

    Default Re: Regenerative circuit?

    A couple of negatives to keep in mind about regen use on FEL dump circuits.

    Since as Kenny D stated it dumps faster it is also much harder to feather the dump function. Example is trying to keep the loader level while raising.

    You also loose dump force. Example: it is much more difficult to tilt the bucket down to dig a little deeper into the ground if it it is already firmly on the ground.

    There are other ways to prevent cylinder cavitation from over running loads but this is the least expensive option so.

    Roy
    Artificial Intelligence will never overcome natural stupidity.

    Branson 2400H MMM & FEL

    JD 112

    BX1850 gone but not forgotten

  7. #7
    Veteran Member
    Join Date
    Apr 2009
    Posts
    1,023
    Location
    Port Angeles WA

    Default Re: Regenerative circuit?

    Quote Originally Posted by oldnslo View Post
    A couple of negatives to keep in mind about regen use on FEL dump circuits.

    Since as Kenny D stated it dumps faster it is also much harder to feather the dump function. Example is trying to keep the loader level while raising.

    You also loose dump force. Example: it is much more difficult to tilt the bucket down to dig a little deeper into the ground if it it is already firmly on the ground.

    There are other ways to prevent cylinder cavitation from over running loads but this is the least expensive option so.

    Roy
    Agree there are some negatives....many times we want to utilize the faster motion that the regen allows, but our system is not designed to handle the the multiplied flow that is generated....and huge back pressures are generated...a 4"cylinder with a 2"rod (4:3 ratio) will supply 10 gpm from pump and 30 gpm from the rod side to a total of 40gpm into the capped side....with a regen spool in the control valve, it is a no brainer that back pressure will be an issue, especially when we tend to dimension hoses and control valves for pump flow instead of real flow...
    then a inline regen valve placed on the cylinder will be more efficient...

    Well dumping (or lowering) a load is still 100% lost potential energy....regen or not doesn't matter

    I can add another benefit with regen.....a 6-7 function knuckle boom logging equipment crane is always operated with 3-5 functions simultaneously moving. Pump flow is then many time limited (bottle neck), and regen can support pump to supply fill flow on functions that more or less extend from load of gravity....like stick (2nd boom) in/down and telescope out...

  8. #8
    Platinum Member
    Join Date
    Jan 2007
    Posts
    584
    Location
    Manhattan, Kansas
    Tractor
    NH TC45D

    Default Re: Regenerative circuit?

    It is my understanding that regenerative circuits use and eductor to create a large volume of low pressure flow from a small amount of low pressure flow. The source of the oil is the return side of the cylinder.

    The following valve is an example of one that uses an eductor.

    Prince LSR Rapid Extend Logsplitter Valve - Cylinder Services

    Chris

  9. #9
    Super Star Member J_J's Avatar
    Join Date
    Sep 2003
    Posts
    16,877
    Location
    JACKSONVILLE, FL
    Tractor
    Power-Trac 1445, KUBOTA B-9200HST

    Default Re: Regenerative circuit?

    How many of you had to look up the word [ eductor ]? Even the spell check hit on it. I have never heard or used it before. It appears to be an injector type unit.
    J.J.

    When I works, I works hard. When I sits and thinks, I goes to sleep.

    Git er done.

  10. #10
    Veteran Member
    Join Date
    Apr 2009
    Posts
    1,023
    Location
    Port Angeles WA

    Default Re: Regenerative circuit?

    eductor is obviously a term that is used in injector systems,,,like Venturi tube design....

    Spell check misses most of the industrial terms...use google

    NO dynasim, it is NOT an eductor in the valve....

Page 1 of 3 123 LastLast

Similar Threads

  1. At Home In The Woods
    By Obed in forum Projects
    Replies: 5790
    Last Post: 08-20-2014, 04:34 PM
  2. Voltmeter - what am I missing?
    By Dyer, retired in forum Customization
    Replies: 54
    Last Post: 09-15-2008, 05:03 PM
  3. Relay Circuit, Switch, and 12V Receptical installed on 3320 - Pics and Instructions
    By BloomingtonMike in forum John Deere Owning/Operating
    Replies: 8
    Last Post: 08-16-2006, 11:30 PM
  4. No "glow" Glow Plugs
    By ToolManRick in forum Chinese Tractors
    Replies: 38
    Last Post: 10-19-2004, 06:06 AM
  5. 3 way or 4 way valve needed on BX?
    By MrJoe in forum Kubota Buying/Pricing
    Replies: 7
    Last Post: 06-30-2004, 02:34 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
© 2014 TractorByNet.com. TractorByNet is a registered trademark of IMC Digital Universe, Inc. Other trademarks on this page are the property of their respective owners.