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#16 TUDOR OFFLINE  

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Posted May 27, 2015 - 11:44 PM

Keith, I think I just figured out what you are saying. These are open center valves, meaning pressure is on both sides when the engine is running. What if I take the return for the first valve to the feed for the second, then run a new return line back? Wouldn't that be the same?

attachicon.gifFront Hydraulic lines #3.JPG

This is the correct circuit.

 

The implement lift relief valve on the Eaton charge pump limits all pressures down stream to its factory setting (750 psi). Since the relief dumps excess pressure directly back to tank, no power beyond kit is required if additional valve sets are added.

 

If there was a concern about valve set return side strengths, a lot of systems with 2 or more valve sets would be in trouble. The return side has to handle as much pressure as the pump side. A power beyond kit does not magically make back pressure from a valve set downstream disappear. All components upstream from a second valve set are under whatever pressure is required to do its task to the lesser setting of the implement lift relief valve or the relief valve in the second or subsequent valve set.


Edited by TUDOR, May 27, 2015 - 11:46 PM.

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#17 skyrydr2 ONLINE  

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Posted May 28, 2015 - 03:24 AM

This is the correct circuit.
 
The implement lift relief valve on the Eaton charge pump limits all pressures down stream to its factory setting (750 psi). Since the relief dumps excess pressure directly back to tank, no power beyond kit is required if additional valve sets are added.
 
If there was a concern about valve set return side strengths, a lot of systems with 2 or more valve sets would be in trouble. The return side has to handle as much pressure as the pump side. A power beyond kit does not magically make back pressure from a valve set downstream disappear. All components upstream from a second valve set are under whatever pressure is required to do its task to the lesser setting of the implement lift relief valve or the relief valve in the second or subsequent valve set.

Bob if that were the case then why even have power beyond capabilities?
Also the Eaton 11 charge pump has NO relief at all.
The system pressure is relieved at the valve, this is why they squeal at full up and full down.
And if a valve is constructed with power beyond capabilities you better use it,as it has 2 circuits designed into it!! High pressure and low pressure or return pressure that is a max of 150 psi, any more would blow out hoses and coolers,and the valve body it self Depending on the brand,as some are tougher than others.
This can get quite complicated and lengthy, but doesn't need to.
You just need to follow recommended procedures, if the valve has this capability of power beyond, use it.
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#18 KennyP ONLINE  

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Posted May 28, 2015 - 05:12 AM

I spoke with Keith yesterday afternoon and this is how I will run the lines to the new valve. It is an open spool, so pressurized fluid will pass through to the return, thus feeding the existing valve. This will effectively get around the power beyond on the existing valve.

Front Hydraulic lines #4.JPG

 


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#19 Alc ONLINE  

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Posted May 28, 2015 - 05:33 AM

Not sure how the valveing  works on the Ford but my PK w/fel the way the factory did it was from the pump to the 2 spool loader valve relief at 1250psi ( no power beyond ) the return feeds the single valve under the seat for 3 pt . relief at 1000 psi . I do know that not all valves can be plumbed like that , on my Ford 3400 utility tractor I wanted to run the flow  through the  4 spool backhoe valve then the new outrigger valve ( that didn't have a relief built in ) but as soon as I tried using the outriggesr all the handles started moving on the 4 spool valve ! That shot that idea    :(


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#20 KennyP ONLINE  

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Posted May 28, 2015 - 05:59 AM

Keith (skyrdr2) was a great help figuring out what I could do with the parts I have. Now I just hope I have enough lines to make it work. This will be my first time doing something like this. I have some pieces of 3/8" steel fuel line I can practice the flares with. Then I can figure out what to use the valve for! :bigrofl:


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#21 TomLGT195 OFFLINE  

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Posted May 28, 2015 - 08:35 AM

Kenny , I found adding a little oil/ lube to the end of the pipe and to the flare tool head help when trying to flare such big lines as 3/8"


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#22 TUDOR OFFLINE  

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Posted May 28, 2015 - 02:42 PM

Bob if that were the case then why even have power beyond capabilities?
Also the Eaton 11 charge pump has NO relief at all.
The system pressure is relieved at the valve, this is why they squeal at full up and full down.
And if a valve is constructed with power beyond capabilities you better use it,as it has 2 circuits designed into it!! High pressure and low pressure or return pressure that is a max of 150 psi, any more would blow out hoses and coolers,and the valve body it self Depending on the brand,as some are tougher than others.
This can get quite complicated and lengthy, but doesn't need to.
You just need to follow recommended procedures, if the valve has this capability of power beyond, use it.

I stand corrected, the implement lift circuitry is a customer supplied option on Eatons. See the link in the first post of this thread for the flow diagram on page #11 of the PDF.

 

Keith, you're the one who taught me how a power beyond kit works. I just had to do a bit more research to get it locked in.

 

Relief valves work on the principle of pressure differential between the high side pressure from the pump and the low side pressure of the tank. In order for them to work correctly, they must have unobstructed flow directly to the tank. If another valve set is inserted into the system downstream from the relief valve, relieved flow meets an obstruction should a valve be cycled at the same time as a valve in the first (relieved) valve set setting up an additive pressure problem. Using acase of a 750 psi relief setting as an example, the first valve set has 750 psi to work with before the relief sends fluid back to tank via a second valve set. Should the second valve set be actuated, the pressure that it requires to do work is added to the relief pressure (differential pressure), and there is no relief protection since the pressure differential seen by the relief in the first valve set is zero. The same pressure exists on both sides of the relief valve. With relieved flow diverted to do work with the second valve set, pump breakage is pretty much guaranteed to happen at some point.

 

This issue crops up when the relief valve is in the valve set, not when it is at the pump as with an Eaton hydro and the relieved flow goes into the hydro case to drain back to the reservoir.

 

The return side of a valve set that can have a power beyond kit installed has a common chamber and two outlet ports, one for return to tank and the other for power beyond. Without the kit, either can be used for the return line.

 

The kit includes a plug designed (for that specific valve model) to separate that chamber into 2 chambers, one for discharging fluid going over the relief back to tank, and the other to send fluid on to successive valve sets in the primary circuit. The relief valve in the valve set ensures that maximum pressure allowed in the rest of the system is the relief setting, the same as in the case of the hydro with an implement relief.

 

Note: A valve set with no integral relief  will not have provision for power beyond. It does not necessarily follow that a valve set with an integral relief will also have a power beyond capability. Some valves found on GT's, specifically FEL's, fall into the second category. Valve sets on the GT hydros rarely have an integral relief since there is a relief at the charge pump. Eaton 11's  seem to be an exception.


Edited by TUDOR, May 28, 2015 - 03:08 PM.

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#23 KennyP ONLINE  

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Posted May 28, 2015 - 04:36 PM

Well, my plans are shelved for now. I got the valve, link and handle all ready to go in, but I do not have enough correct fittings to attach lines to the valve. I need at least 2 straight JIC fittings for the pressure and return. Then I need 2 90° (or 45°) fittings for the cylinder lines, one of which needs to extend out further for clearance of other lines/fittings.

Here is what I have.

2015-05-28 16.13.47.jpg

 

Here is one fitting next to a 90° I took out and is has a very small hole in it. What is it's purpose?

2015-05-28 16.14.25.jpg

 

Here's the pics of the fit up of the valve & handle.

2015-05-28 15.16.27.jpg     2015-05-28 15.16.42.jpg

2015-05-28 15.16.57.jpg


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#24 Chopperhed ONLINE  

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Posted May 28, 2015 - 05:03 PM

 

 

Here is one fitting next to a 90° I took out and is has a very small hole in it. What is it's purpose?

attachicon.gif2015-05-28 16.14.25.jpg

 

 

I  would bet money that it's to limit flow for some reason.  Probably to control cylinder speeds or something similar.


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#25 KennyP ONLINE  

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Posted May 28, 2015 - 05:22 PM

Hey, Keith (skyrydr2), if you want I still have an extra Dukes valve that can be used to make the Power Beyond fitting. I can ship it out next month.


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#26 skyrydr2 ONLINE  

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Posted May 28, 2015 - 05:49 PM

Sure thing Kenny, that would be awesome. That tiny hole would be called an orifice in hydraulic terms and is used for many different apps . one is speed control another is for load equalization, you can drill it out and use that fitting normally. What exactly do you need for goodies? I might just have them in my bag of goodies;-)
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#27 skyrydr2 ONLINE  

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Posted May 28, 2015 - 06:04 PM

Bob, you can't use the pb fitting for a tank return unless it is properly ported, and you still have to have the return port plumbed to tank, as it is separated when pb is ported via the special fitting. The pb port is for high pressure flow only unfortunately. In Kenny's case it should be fine in the latest version of his plumbing diagram as te diamond ported valve can take what ever the charge pump can dish out, and when I get the fittings done he will have the option open to make things politically correct LOL .
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#28 KennyP ONLINE  

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Posted May 28, 2015 - 06:47 PM

Sure thing Kenny, that would be awesome. That tiny hole would be called an orifice in hydraulic terms and is used for many different apps . one is speed control another is for load equalization, you can drill it out and use that fitting normally. What exactly do you need for goodies? I might just have them in my bag of goodies;-)

On the valve I want to use, I need 2 straight JIC fittings to run the pressure and return lines. For the cylinder lines, I can use one of my 90° fittings, but the one most rearward will need to come out from the valve further to clear the first one. That could be a 45° with an extension on it. Not much room on the valve to get fittings into. It's really as it is in the pic I posted above., just JIC fittings. I will still have to get lines for the cylinder, though.

I may be able to make it work with the non-JIC fittings as I have the ones I took out of the valve and another whole setup still attached to a drive axle. Plus some hoses.



#29 KennyP ONLINE  

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Posted May 29, 2015 - 04:29 AM

I forgot i have the hoses on the cylinder I may be able to use. One may work for the return to pressure on the valves. Hardest will be the charge pump to the new valve as it will need bent and cut to length. I'll look again today at what I may be able to make work. Then I will need long lines out to the front cylinder. It would be nice to hook it up like the Kit shows with quick connects.



#30 TUDOR OFFLINE  

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Posted May 29, 2015 - 04:50 AM

Bob, you can't use the pb fitting for a tank return unless it is properly ported, and you still have to have the return port plumbed to tank, as it is separated when pb is ported via the special fitting. The pb port is for high pressure flow only unfortunately. In Kenny's case it should be fine in the latest version of his plumbing diagram as te diamond ported valve can take what ever the charge pump can dish out, and when I get the fittings done he will have the option open to make things politically correct LOL .

The return side of a valve set that can have a power beyond kit installed has a common chamber and two outlet ports, one for return to tank and the other for power beyond. Without the kit, either can be used for the return line.

 

I'm not sure as to what you are referring. Both ports access a common chamber. You can bend a welding rod into one port and have it come out the other except as noted in my above post. If there are not 2 ports on the return side, there is no provision for power beyond circuitry.






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