Spool valve

[hermit]

The search still don't work. What is the difference in "open"center and "close" center spool valves? I need to operate a hyd motor, but, flow on thru when in neutral to another valve bank, splitter valve, log clamp etc. The log clamp and so forth has 1/2" ports, will that slow down flow to much to do it this way ? My pump is 1" ports 30 gpm.

 

[augercreek]

open center is what you want if you are having another valve down stream of it that way you can operate all valves at any time.

 

[blades]

The other term used to describe the valve you want is "power beyond". So the description of the valve should read open center with power beyond

 

[hermit]

Is there a way to tell if a valve is power beyond, just by looking at it ? All I know about this valve is it has 1" in/out and 3/4" work ports. Also I wonder if I put a valve down stream that has 1/2" ports will that restrict the flow too much ? Thanks for the info so far.

 

[CJ1]

Is there a way to tell if a valve is power beyond, just by looking at it ? All I know about this valve is it has 1" in/out and 3/4" work ports. Also I wonder if I put a valve down stream that has 1/2" ports will that restrict the flow too much ? Thanks for the info so far.

You either have to test it with air or know what valve you have. The mfg could tell you with a p/n or post a pic of it and I may be able to help also. Most valves are 3/4 in and out with 1/2" work ports. If you actually have a valve with 1/2 in and out it will only be rated at 15 gpm or so. A valve with 1/2 work ports is marginal at 25gpm, they will do 30 but will build more heat and backpressure. your valve with 1" in/out and 3/4" work ports will be rated around 40 gpm. Post a pic and let us look at it. CJ

 

[Iron man]

Ive been trying to figure out a good valve for when the day comes and I build a log lift and it seems a duel spool would be good for that.But running a hydraulic powered motor I would guess you would need to use a power beyond.I have no clue exactly how those work; and have a flow control valve to have the ability to regulate the speed of the motor if needed.

 

[hermit]

I haven't purcheased a valve yet, I am trying to figure out what will work first, as I don't have money to throw around. The valve I am looking at is on ebay item # 260771363106.

 

[CJ1]

Hermit you first need to figure out what valve you have or you will be throwing money away if you guess wrong. You would not buy parts for a ford and expect them to fit a chevy right?

Iron man, there is a couple of different ways you can do this. Either pm me or start a different thread so we don't hijack this one.

CJ

 

[kevin j]

Open center ports P to T, A & B are blocked, in neutral. It is used with fixed gear pump where constant flow must go from P to T ports in neutral. (Technically I think it is tandem center, and open center is really PATB, but open center is the most commonly used term for what you are looking for.


Closed center has PATB all blocked in neutral and is used with variable, pressure compensated pump.


Closed center valve on gear pump = full flow across relief valve pressure at all times when cylinder is not moving = full hp into heat.

Open center valve on pr comp pump = full flow across open center when in neutral, pump runs against its stops at full flow, and if the resulting pressure is low, the pump will trash its slippers.


Almost all splitter projects have fixed gear pumps and need open center valve.

 

[hermit]

Let me run this by one more time. Firewood processor, One bank of four valves 1/2" in-1/2" out, then one valve for splitter 3/4" in- out 1/2" work ports, Now I will rearrange this setup by, One valve 3/4" in-out, 3/4" ports for hyd chainsaw, then splitter valve, then the 4valve bank. Will this work in series or will the 1/2" valve restrict the flow to much ? and do I need the power beyond between the saw valve and splitter valve ? I think I have confused myself now.

 

[Iron man]

I'm no expert on this subject but Ill throw some thoughts out there.It sounds to me you have or are building something that requires some significant oil flow to maintain a proper operating pressure.First off do you have a pump capable of supplying the flow needed for everything if they were being operated all at one time at max.The chain saw will need constant flow to maintain a good cutting speed so a valve that simply opens and closes Td in before the splitter/clamp valve might work.The residual flow not used by the saw should be sufficient to operate everything else if the pump is up to the task.Sounds good but everything sounds good until you learn better.

 

[Misfit138]

The search still don't work. What is the difference in "open"center and "close" center spool valves? I need to operate a hyd motor, but, flow on thru when in neutral to another valve bank, splitter valve, log clamp etc. The log clamp and so forth has 1/2" ports, will that slow down flow to much to do it this way ? My pump is 1" ports 30 gpm.

If you go to google and type in

spool valve site:arboristsite.com

or any other search term, you will get what you are looking for.

 

[CJ1]

Let me run this by one more time. Firewood processor, One bank of four valves 1/2" in-1/2" out, then one valve for splitter 3/4" in- out 1/2" work ports, Now I will rearrange this setup by, One valve 3/4" in-out, 3/4" ports for hyd chainsaw, then splitter valve, then the 4valve bank. Will this work in series or will the 1/2" valve restrict the flow to much ? and do I need the power beyond between the saw valve and splitter valve ? I think I have confused myself now.

Yes the 1/2" in and out valve wil be too restrictive for 30GPM, and you have to have power beyond in the first bank to feed the second valve bank. Most processors have 2 or 3 circuit pumps to feed each bank seperatly. CJ