Valve Spool, Control Valve questions

[woodlandfarms]

I have a very basic question to ask. What is the difference between various valve spool controls. I am looking to add another remote, and there appears to be 4 different types (or at least they are labeled that way).

Log Splitter Valve
Motor Spool Valve
Control Valve (the most common)
Electric control valve

Log Splitter valves seem to be the cheapest, and motor spools the most expensive.

I get what electric is (although I have a question, can you "feather" an electric valve - meaning slowly let the juice flow for precision work or is it just on and off)

Can anyone help a layman get through these vageries?

Thanks

[Trails2004]

I'm certain some of the experts will be able to answer your questions- however they may need more information.

Do you have a specific need for a valve? or what do you want the valve to do??

[dfkrug]

Very briefly:

A Log Splitter Valve will go into detent (stay in that position) when you
first activate it (push the lever). What this does is extend the cylinder
all the way until it hits the end of its stroke, allowing you to leave it
untended while it does its work. When it reaches the end of its stroke
it automatically goes out of detent and retracts, ready for the next log.
You don't need these kind of spool valves for a log splitter. A simple DA
spool valve will work.

A motor spool valve is another type of spool valve that allows fluid from
the motor to return to the reservoir after you return the control lever to
neutral. You want this for some applications where the momentum of the
motor will cause large spikes in the pressure as you close the valve.

"Control Valve" is a generic term that could refer to many kinds of valves,
spool valves, ball valves, solenoid-controlled valves, etc.

An electric valve usually has a solenoid that acts directly on a spool or
poppet. Most will be all on or all off, but there ARE proportional electric
valves. Your common solenoid valves can not be feathered, but
proportional electric valves do provide volumetric flow control. That's
a whole new world of electrically-controlled hydraulics.

[beenthere]

And I thought the Log Splitter valve would NOT go into detent on the splitting direction/motion (for safety) but would go into detent on the return stroke.

Upon return, it would kick into neutral.

[woodlandfarms]

dfkrug... thanks for the info. What is DA?

Also, what this is for is a grapple control valve. The logs splitter sounded interesting cause I could "command" it to open and not have to keep a hand on the valve.

The ideal valve body would be small. I am also trying to figure out how to mount it so I can position this control properly.

JJ knows that space is limited on my tractor, and while I have to be economical on this project I have to also balance other factors.

dfk, or anyone else. Can you explain a little bit more on the motor spool valve. I thought all valves (if open center) would send fluid back to the tank in "nuetral".

Ahh,,,, jeez... one more question. When you say volumetrics, you mean if I momentarily open and close the switch it will let fluid through... The electric system seem to me to be not a great control for running stuff as it would be jerky, not chance of feathering. BUt I see lots of heavier equipment using it so clearly I am missing something.

ps... Trails. I was raised in Powell, WY. I SOOOOO miss that part of the world.... You are a lucky guy even though it is Lander ;-)

[dfkrug]

And I thought the Log Splitter valve would NOT go into detent on the splitting direction/motion (for safety) but would go into detent on the return stroke.

Upon return, it would kick into neutral.

Actually, that is how I would set it up, too (for safety). I wonder if you can
plumb these valves 2 different ways? I admit I have not played with them
much, but I do have one here that I repaired....a HF unit with a gummed
up internal ball valve that kept it from springing back to neutral when
it hit relief.

[dfkrug]

dfk, or anyone else. Can you explain a little bit more on the motor spool valve. I thought all valves (if open center) would send fluid back to the tank in "nuetral".

Ahh,,,, jeez... one more question. When you say volumetrics, you mean if I momentarily open and close the switch it will let fluid through... The electric system seem to me to be not a great control for running stuff as it would be jerky, not chance of feathering. BUt I see lots of heavier equipment using it so clearly I am missing something.

In the motor valve, the WORK PORTs can return fluid to the tank when
the valve is OFF, In a simple spool valve intended to control double-
acting (DA) cyls, the work ports are cut off when the valve is OFF (neutral).
The pump sends fluid to the tank or next valve when your valve is OFF, in
an open center system.

Proportional controls are not fully off or on, as your solenoid valves are.
Also, heavier equipment often uses variable displacement hyd pumps for
additional hyd control.

[Trails2004]

.....
ps... Trails. I was raised in Powell, WY. I SOOOOO miss that part of the world.... You are a lucky guy even though it is Lander ;-)

I was raised in Casper- So I think I moved in the right direction- I guess you went a little further West than I did

It nice to hear from other Wyomingites- there arent many us around

Go Pokes!

[Wayne County Hose]

The solenoid, electric, whatever you want to call them valves, can be opened a pre-determined amount by controlling the voltage to it. Let's say your system is 24 volts. Applying 24v would open it fully, 12v halfway. The more voltage, the more open. The voltage creates a magnetic field. The magnetic field pulls the valve off of it's seat and lets fluid flow. So, the more voltage, the more magnetism, the more fluid flow. I know AKKAMAAN must have a drawing on this. He must be sleeping today.

Carl, sounds like a detent valve may work for you. Hit the lever into detent and it opens all the way. Might even be good for closing too. Would only let it close to a certain force to prevent wrecking your equipment. If you need more holding force, you could hold the lever manually.

[J_J]

Carl,

Do you have the QA hyd circuit? If so, then I would use that for the grapple by diverting the fluid from the QA circuit for the grapple. There are selector/diverter valves, that will switch the fluid from the QA circuit to the grapple circuit, using a switch to switch circuits. .

https://www.surpluscenter.com/item.a...name=hydraulic

You can do it cheaper with this. Manual control,
https://www.surpluscenter.com/item.a...name=hydraulic

You could also switch the hose fro the QA cyl to the grapple cyl,for a real cheap way to control the grapple.

On my three gang valve, two are for th joystick, and the other one is for the aux circuit.

I use the third lever for my tree snipper, or grapple.

The most convenient way is the solenoid valve setup.