Wood processor build hydraulic questions

[muddstopper]

I those 4 functions are all you need, saw, saw cyl, conveyor and splitter and you have to buy a control valve anyways, One valve to control the splitter, then buy a three spool valve to run the saw, conveyor and saw cyl. You can use 2 flow controls to control the conveyor and saw cyl speed. You never said, is you slasher saw complete where all it needs is the hyd connected. If so, it may already have a sequence valve plumbed in. The sequence valve would allow you to run the saw cyl and saw off one spool valve.

 

[ChoppyChoppy]

I do get that but with a 6 second cycle time on the splitter the only thing I could really have time for would be raising the saw back up. Still trying to do this on a budget. My goal is to keep it at 5000 or less. Right now I am in it 3600 and have 90 Percent of everything I need to make that goal a reality. I emailed prince to see what they had available for valving and recommended layout. I was reading some more on hydraulics and if I was to aquire power beyond valves I would be able to use them in series. Still looking in the stacked valve options. Also found a valve that Bailey hydraulics carries that is 40 gpm. Calling today to find the specifics

6 sec cycle is awful slow on a processor. My processor is about 4-4.5 sec and it's slow. Half that time would be about right.

Can certainly do other things while waiting. I'm moving the log to ready for next cut and starting the cut while the splitting is going.

 

[Dieselb2487]

It does have some valving on it. Not sure what they are though. I will take some pictures and maybe that will help. One is teed in with a knob u can turn and the other has a plunger that activated a valve when the saw is in the up position

 

[muddstopper]

I dont know anything about how a slasher saw is supposed to work. I know that they can be operated from the cab of a knuckleboom loader so I am just assuming that most of the hydraulics are self contained. Work one valve in the loader and the slasher divides the oil flow. That is why I think the saw may already have the sequence valve, but someone more familar with those type saws could give better information. Might be able to look up the hyd schematics online, do you have a model number, brand, to identify the slasher.

 

[Dieselb2487]

First valve is a gresen 1140-000. It is depressed when the saw is in the up position. Second valve is a A something Dennison valve. I can't read the first part of the tag. The lift cylinder had separate lines that would of connected to the Prentice loader. So that's why I'm assuming I need a separate valve for that function.

 

[Dieselb2487]

I had assumed the gresen valve was there to bypass some flow when the saw is in a no load condition. Also thought it might be used as the coast shutdown since it's tied to the supply and return lines? Any input appreciated.

 

[kevin j]

Might the spool with the spring start the saw blade spinning when the arm comes down enough to push on that spring loaded spool?

Are tyhere only two lines connecting to the boom/excavator/whatever drives it? If so, the arm to move and the saw to spin are being sequenced somehow, and controlled to not stall the blade.

Hard to say, the valve may be a cross port relief valve to take a shock upon startup. I suspect it is propretory and there is more in there, so that it does the startup and anticav both.

 

[Dieselb2487]

Separate set of lines would of been connected to run the lift on the sawblade they are ran separately from the 1 inch lines that are ran to the two valves pictured that run to the saw.

 

[kevin j]

I assumed your conveyor was outfeed and continuously running. If it is infeed and intermiitent, then your heat loads are much less.
I would still add a third, small pump, into a small power beyond spool valve for conveyor and cylinders, and take the PB out to the saw circuit.

However, to use from the two pump circuit, I would put a main relief valve after the pump (because priority dividers can block flow under certain conditions), then a priority flow divider. That may be hard to find one with 40. Gpm capability but 3-6 gpm out the priority.

Priority dividers can be adjustable, but they take a constant flow out, say 5 gpm, regardless of input flow which varies as the engine speed varies. Think of a power steering circuit. A proportional divider (say 95%/5% just for illustration) would have wicked fast steering reaction at high engine speeds, but nothing at idle. Priority is constant outlet flow. The other side (say 35 gpm) will be throttled from the load pressure when the conveyor or cylinders run from the priority, so that is a significant source of heat, but hopefully brief.

Take that 5 gpm flow into a multi spool small valve with Power Beyond ( and necessary reliefs or flow controls). Run conveyor and cylinders from small valve. T port goes to tank, and is the return when the valve circuits are working. PB port (which is where the 5 gpm goes when valve circuits are not being used) goes to a tee back ahead of the main 4o gpm splitter valve.
That way, the 5 gpm is not wasted to tank when not being used, yet has full pressure available if you want to run cylinders or conveyor while the cylinder is splitting. The spltting would just slow down briefly, then speed back up. Both circuits get full pressure/force, just reduced flow/speed for a bit.

I would NOT try running the T port of a two ported (without PB port) valve in series back into the tee into the main circuit. You may be lucky if the T cores of the casting are strong enough to take full pressure, but they are not designed to do that. Casting may crack, or the orings on ends of the spool may damage and leak. Or they may work fine for a while. Depends on casting design. Pressure drops would be additive, not referenced to tank pressure, so the small valve and the splitter valve would lose pressure/force or stall when both were operated together. They don’t each get 2500 psi (or whatever). They total up to 2500 in series, so one may get 1500 and one 1000 for instance. If loads are small, no problem. If loads are bigger, one or both will stall.




Kcj

 

[Dieselb2487]

So the easiest solution would be to tag on one more pump that has let's say 5-10 gpm available to run my conveyor and saw lift. Just purchase power beyond valves for those functions so I can keep that circuit separate. Just have one 40 gpm pump for the saw, one 40 gpm pump for splitter and the small 5-10 gpm pump for accessories. I can buy small gear pumps that size from surplus center for under 100 bucks. Just have to figure a way to couple it to my through shaft on my other two pumps. Seems then I could just use generic easy to find valves for the accessories circuit. What's your input on going that direction?

 

[kevin j]

yes, that is what I am describing.

I think the extra pump will cost less than the circuit parts needed in the 40 gpm side to rob from there.

If you don’t want to add the 5 gpm back to the split circuit, you would not even need the small valve to have PB, you can just take it to Tank. I would certainly do the PB. adding 5 gpm to the 40 speeds up split at very minimal cost.

 

[Dieselb2487]

So I think I nailed down a stack valve setup for my accessories circuit. I went with a 4 spool because I do intend to at a live log load setup at some point for sure and if I do an adjustable wedge I would have a spool for that. Wondering if this seems right to you guys?

 

[kevin j]

-PB outlet seems right
-Open center core seems right
-Inlet with RV seems right
-Flow rating you will need to check
‘Rating’ is at some pressure drop. It is not some exact cutoff point like a fuse. Larger valve = less pressure drop. More flow through valve = more pressure drop. Mainly you want low pressure drop in center core as that is continuous.
-So two motor spools, one for infeed conveyor and one for later log deck? Sounds right. Slow speed and minimal overrunning load, so don’t need any load control or brake valving
-what is cylinder circuit for? Wedge lift probably? Edit: reread first post. saw lift
-Then what is the cylinder spool with float? Float is typically on a boom circuit of front loader or grader blade. Edit: reread first post, wedge lift, then put into float position once wedge is started? Probably easier to just have slotted rod connection so wedge can float up, but not down. Not have to manually shift to float. But float position doesn’t really have any drawbacks if you don’t use it as long as it is for DA cylinder.

Not cheap, but not unusual for MSRP. I am used to wholsesale prices so can’t comment. Unlikely to find in used or surplus, so new stack valving is probably only choice

 

[Dieselb2487]

Was considering the float valve for saw lift . Thought maybe I could use that with a needle valve for downward control. Would be easy to get a cutting speed dialed in. But I would do whatever is recommended. It had said 12 gpm nominal 16 gpm Max on that valve stack.

 

[kevin j]

oh that makes sense now I didn’t know what kind of a circuit you had for the saw lift. ideally you want to control pressure down but the next best way would be using float like you’re describing put it in the float and let the pressure compensated flow control control the lowering rate. A straight needle valve or an orifice might be a little hard to control with the varying load. and you’d have to set the fc speed such that saw didn’t bog at the maximum diameter of the cut but that can be sorted out pretty easy.

Next question is whether or not you need 12 gallons a minute nominal valve size. Maybe you can get a smaller valve and save significant money. do you know five or six gpm is what you’re aiming for? If you have your motor sized for the conveyor and the cylinder sized for the future live deck or anything like that then you can work backwards to calculate what flow you need. One of the beauties of running a separate third small pump for your conveyor is that you can size it to run at a reasonably low pressure and larger flow. With a fixed pump flow thus speed will be constant and if it needs more torque/power it will push pressure as needed by the load. It gives you more flexibility if you underestimate the load.

do you use excell spreadsheet program? if you’re familiar with that send me a PM with an email address and I’ll send you calculation spreadsheet for motors cylinders pumps flows line sizes etc. just hydraulic components in general not specifically for a log processor

 

[kevin j]

Pm’s going back and forth. Will post here as final designs.

 

[Dieselb2487]

Here are some pictures of the progress. Conveyor and hydraulic tank will be mounted and completed this week. Shooting for 1st of the year to be running logs through it.

 

[rancher2]

Looks like your making some process. Are you installing a governor on the engine? How big of hyd tank and cooler are you running on the slasher saw?

 

[Dieselb2487]

Running a 100 gallon hydraulic tank so I am pretty confident I will not need a cooler but I am going to run it as is and monitor temps. Instead of doing a conventional governor setup I am going to use a universal cruise control setup. Should work at least as good if not better than a traditional governor and they are very reasonable price wise.

 

[rancher2]

Dieselb2487 Any updates?