5,000 psi 2 Stage Hydraulic Pump?

[Josh A]

Guys,

I'll preface my questions below with a little back ground about myself. I am an oilfield engineer with 10 years of experience. My expertise is fluid dynamics (pumping and flow of the various fluids in drilling wells) in well bores. Now I know a lot of "self educated" people with a degree from "The School of Hard Knocks" have little use for engineers and I understand why trust me. Most engineers only work in theory but where I excel is taking the theory (which isn't my strongest suit lol) and working with people with self taught experience to come up with the best solution to issues. I also am a firm believer and have a bad case of the Redneck axiom "More Power or More Gas is Always Better"!

Now to the question. I've been reading the log splitter builds with interest and decided I need to start learning more about hydraulics. As I need a better log splitter I am looking to build my own for the learning experience. Using the theory bigger is always better Im considering a 5,000 psi two stage hydraulic pump. I've looked at a lot of pump on the typical web sites and read a lot of threads but aren't seen one yet. Do any of all know if this pump is even manufactured and where I could find one?

Josh

 

[djones]

You've come to the right place since most of us have built one or two of our own splitters over time. As to your question, a 5000 psi pump would do irreparable damage to many of the current hydraulic lines in use on most splitters since braided hydraulic line of 1/2" to 1" is only rated at 3250 psi so you can see where that would leave you, ---- covered in oil. Sticking to the basic 2 stage pump on a motor of your own choosing with a cylinder sized to your operations will get you all the splitting power you'll need to split any of the hard woods you'll likely come across. I'm sure there are a few good ole rednecks boys out there that will follow up with more powerful suggestions and some helpful tips so keep watching this thread.

 

[motoman3b]

Coming from a guy who had a hydraulic cylinder failure, the end cap exploded on me I wouldnt want an extra 2-2.5k of pressure in that cylinder I feel lucky I only came out with one small bruise on the leg and covered in hydraulic oil.

 

[leon]

wood splitter et. al.

Guys,

I'll preface my questions below with a little back ground about myself. I am an oilfield engineer with 10 years of experience. My expertise is fluid dynamics (pumping and flow of the various fluids in drilling wells) in well bores. Now I know a lot of "self educated" people with a degree from "The School of Hard Knocks" have little use for engineers and I understand why trust me. Most engineers only work in theory but where I excel is taking the theory (which isn't my strongest suit lol) and working with people with self taught experience to come up with the best solution to issues. I also am a firm believer and have a bad case of the Redneck axiom "More Power or More Gas is Always Better"!

Now to the question. I've been reading the log splitter builds with interest and decided I need to start learning more about hydraulics. As I need a better log splitter I am looking to build my own for the learning experience. Using the theory bigger is always better Im considering a 5,000 psi two stage hydraulic pump. I've looked at a lot of pump on the typical web sites and read a lot of threads but aren't seen one yet. Do any of all know if this pump is even manufactured and where I could find one?

Josh

You've come to the right place since most of us have built one or two of our own splitters over time. As to your question, a 5000 psi pump would do irreparable damage to many of the current hydraulic lines in use on most splitters since braided hydraulic line of 1/2" to 1" is only rated at 3250 psi so you can see where that would leave you, ---- covered in oil. Sticking to the basic 2 stage pump on a motor of your own choosing with a cylinder sized to your operations will get you all the splitting power you'll need to split any of the hard woods you'll likely come across. I'm sure there are a few good ole rednecks boys out there that will follow up with more powerful suggestions and some helpful tips so keep watching this thread.

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Befroe you tell me where to stick my API threaded range three casing, tremie pipe with high solids cement grout, marsh funnel, casing chain wrench or pail of thermally enhanced geothermal grout(snicker) from Halliburton-HA/Hello uncle #### Cheney.

I absolutely hate worn out casing wrenches when people do not rebuild them or throw them out,
and they tell you to use them when they have 8 foot cheater bars welded too them or they tell you the casing spinner on the T4 is too slow for ME so I do not use it!!! I loose faith in well drillers when they expect two people to thread casing together with one wrench, and when you have the casing threaded down into the coupler and when you look down the entire 200 foot string is spinning when you are trying to tighten the top joint!!!!!!!!!!!!!!!!!!!!!!




A purchased wood splitter from any of the long standing
maufacturers like Timberwolf Inc. will be a better investment
as ALL AND I MEAN ALL the work has been done for you.


It takes a lot to build wood splitter and for many and most that do its a trial and
error enterprise because the pump is too big, the reservoir is too small or the
cylinder is too big. The bigger manufacturers have approached this with
double acting cylinders that are of tie rod construction.


The other issue is simply whether you can afford to make mistake
and be able to spend money to repair said mistake in design; Hint,
its all ready been done for you...................................................

 

[avalancher]

Guys,

I'll preface my questions below with a little back ground about myself. I am an oilfield engineer with 10 years of experience. My expertise is fluid dynamics (pumping and flow of the various fluids in drilling wells) in well bores. Now I know a lot of "self educated" people with a degree from "The School of Hard Knocks" have little use for engineers and I understand why trust me. Most engineers only work in theory but where I excel is taking the theory (which isn't my strongest suit lol) and working with people with self taught experience to come up with the best solution to issues. I also am a firm believer and have a bad case of the Redneck axiom "More Power or More Gas is Always Better"!

Now to the question. I've been reading the log splitter builds with interest and decided I need to start learning more about hydraulics. As I need a better log splitter I am looking to build my own for the learning experience. Using the theory bigger is always better Im considering a 5,000 psi two stage hydraulic pump. I've looked at a lot of pump on the typical web sites and read a lot of threads but aren't seen one yet. Do any of all know if this pump is even manufactured and where I could find one?

Josh

What the hell are you plan on splitting with a splitter that can generate that kind of pressure? Commercially built splitters generally all range in the 3000PSI range for a reason, and thats because that is about all you are ever going to need, at least for any species of wood found on this continent. If you want to go big, then go big with a higher volume pump that will sing your cycle rate up, and be prepared to wear yourself out trying to keep up. Splitting wood is like an endurance race really, its not the fastest guy that gets there first but the guy who can set a pace and keep it up for hours on end.

 

[motoman3b]

Actually I do recall one company that makes a splitter that uses high pressures.... Cant remember the name of it right now hopefully someone will chime in. If I recall it uses a smaller cylinder 2.5" bore and some special hydraulic booster that creates pressures 8k psi the advantage is lighter splitter that cycles fast but still has alot of splitting tonnage for the nasty stuff.

Did a quick search heres some info on it

SPLITTERS

 

[Steve NW WI]

You're gonna find that it's cheaper to build a 3,000PSI machine with a 5" cylinder (29 tons) vs a 4" 5000PSI cylinder (31 tons), even if you could find a 5 K 2 stage pump, which you won't.

Also don't forget the extra HP needed to spin a higher pressure pump, which is just as easily used to run a higher flow, lower pressure system.

Any combination of pressure and area will get the desired tonnage, mine gets it done with a 7" cylinder and a low pressure vane pump.

 

[origionalrebel]

unless you just like to experiment and spend cubic dollars, stay away from the exotic hi press. stuff. hard to find and hard on the hip pocket. if tonnage is what you're after, use a bigger cylinder. remember when you make one component stronger the rest has to follow suit, else you'll end up with a pretzel for a beam. big cylinder requires big pump volume and big plumbing to make it have a decent cycle time. just my 2 cents

 

[half]

big pressures

Getting up around 5000PSI will cost a fortune in hydraulic parts, you will need multi spiral hose to take the pressure, plus,and [they sell that stuff by the inch] for shock loading,so you would need at least 7500psi rating, and that is big bucks, all valves and fittings would have to be the same rating. i would sell the pump and buy a good brand splitter off the shelf, unless you are going to build a great big processor then you need a big diesel to run it. And at that pressure heat could be a real problem,The tank would need to be a good one too to take that sort of pressure roaring around in it. And how many galls /min would you need to feed it, and how big a tank to store the oil
Really it looks to me like a case of putting the pump in [the too hard basket]

 

[Hddnis]

Actually I do recall one company that makes a splitter that uses high pressures.... Cant remember the name of it right now hopefully someone will chime in. If I recall it uses a smaller cylinder 2.5" bore and some special hydraulic booster that creates pressures 8k psi the advantage is lighter splitter that cycles fast but still has alot of splitting tonnage for the nasty stuff.

Did a quick search heres some info on it

SPLITTERS

They sell those splitters retail for less than $1,800 for the top of the line model.

The 3000psi is standard because they are using uber cheap parts. Many of the splitters hitting the market today are going to 3500 and even 4000 to get the tonnage rating up.

There are lots of industrial and earth moving machines out there that far exceed 3000psi; in fact the little press in my shop does 10,000.

So I'd say go for it. You'll be able to use a much smaller ram for much faster cycle time and still have a bunch of splitting force.




Mr. HE

 

[Whitespider]

Actually I do recall one company that makes a splitter that uses high pressures.... Cant remember the name of it right now hopefully someone will chime in. If I recall it uses a smaller cylinder 2.5" bore and some special hydraulic booster that creates pressures 8k psi the advantage is lighter splitter that cycles fast but still has alot of splitting tonnage for the nasty stuff.

Did a quick search heres some info on it

SPLITTERS

Yep, LogBoss Wood-Splitters... they're made right here in my Iowa county, and of course I own one.

You are correct about the 8000 PSI, although the pump does not generate it, the proprietary and patented "oil to oil piston booster" does... and the cylinder uses all metal seals to contain that pressure. I'm pretty sure you're wrong about the 2.5" bore though, that's what the outside diameter of my cylinder measures. Mine is the 18 ton model (standard is 15), but that's 18 ton of continuous force (not some "peak" rating done with fuzzy math)... I'd put my little 18 ton splitter up against any "box store" splitter rated at 20-25 ton any day, it will out work them every time.

A few more features to point out...

• It weighs less than 200 pounds and stores in less space than a typical lawn tractor... I can lift the beam and roll it around using just one finger or load it in my pickup box by myself.
• It is fully hands-free auto-cycle/auto-throttle... push the lever forward and remove your hand, the engine speeds up, the ram extends, at the end of the stroke the lever flops into retract position, the ram retracts, the lever returns to neutral position, and the engine returns to idle speed.
• Complete 25-inch cycle time is less than 10 seconds.
• Stroke length is infinitely adjustable from the full 25-inches to as little as a 1/4-inch with a simple thumb screw... further reducing cycle time.
• The beam is the fluid reservoir... no extra tanks, caps, vents, and whatnot.
• Except for the single, tiny diameter, flexible line from the pump to the valve, all pressure lines are welded steel.
• The valve spool is easily serviced by removing one jamb nut from the linkage and slipping it out of the bore... and it has only one single, standard o-ring on it.
• It uses a small, round, floating push-plate that pivots and grabs angle-cut rounds without slipping... and keeps all the pressure directly in line with the ram (where it does the most good), eliminating almost all side stress to the cylinder rod and slide.
• Price competitive with "box store" splitters built using cheap(?), off-the-shelf parts... and in 30-some years of use, mine ain't never broke.

Oh... and by-the-way, these guys were building their splitter before you could buy one in a "box store".
There's also a (unconfirmed, by me anyway) story that at one time Sears/Craftsman tried buying the rights and patents, and those good-ol'-boys wouldn't sell... after 4 decades they're still building them one at a time by order.

 

[kevin j]

Force is pressure times area, so you get the same force either way, just by picking the cylinder size. Higher pressure/smaller cylinder.
HP is flow x pressure, so the speed and force are utlimately detemined by engine hp. Small cylinder won't necessarily be faster because the pump is smaller because the engine hp is the same....

And, with a long stroke cylinder, you are limited in small size by cylinder rod buckling anyway, so there is a practical smallest limit.


As equipment got better, hydraulics went for 800 psi to a pretty common 3000 psi range now. Hydrostatic equipment is 5000 psi routine, and many open loop systems are 3500-4000.

The advantages of high pressure are usually in weight and space critical applications (aerospace, testing, downhole, subsea, etc)

The downsides are many: safety, sealing, and whole different technologies are used above about 3000 psi. Hoses go to spiral construction, ports are face seals or split flanges which are larger, cast iron is replaced by durabar or similar ductile iron parts, etc.

But for a home project I don't think the major changes and costs are justified. Most of the mass production components (read: available, mass production and much cheaper) is the 3000 psi range and it s a whole different world in higher pressures.

The intensifiers work because pressures are usually contained in drilled passages and all the outside components are lower pressures. Porta powers and bottle jacks simiilar situation.


kcj

 

[bayard]

2500psi

the splitter i built has 22 gal pump 4inch piston.and a 11 hp honda.at full rpm it will cycle in 12 sec. for one person way to fast, most times 50 to 70% rpms is just right. some big nasty wood ,go full speed.used engin free,used cyl free, new pump 350$, some fittings,lots of welding. keep it simple and strong.k

 

[Whitespider]

As equipment got better, hydraulics went for 800 psi to a pretty common 3000 psi range now. Hydrostatic equipment is 5000 psi routine, and many open loop systems are 3500-4000.

The advantages of high pressure are usually in weight and space critical applications (aerospace, testing, downhole, subsea, etc)

The downsides are many: safety, sealing, and whole different technologies are used above about 3000 psi. Hoses go to spiral construction, ports are face seals or split flanges which are larger, cast iron is replaced by durabar or similar ductile iron parts, etc.

So then...
How did these good-ol'-boys in fly-over-country Iowa design and build hydraulic systems (including the cylinder, ram, seals, valve, booster and whatnot) operating at 8000 PSI... using a few basic machine tools, in a garage, while drinkin' beer... over 40 years ago?? (Yeah, I've emptied a couple boxes with them over the years) Systems that are still working after decades of use... systems that have never been faulted as a safety issue... systems that remain sealed?? Mechanical systems designed to keep force directly in line with the ram so it won't buckle the small diameter rod?? Did aliens turn them on to this set of "whole different technologies"?

Hey, I'm just wonderin'? Maybe beer actually does make you smart!!

 

[Patrick62]

bragging rights

It is all about bragging rights. Come on guys, we all know situation. More, bigger, better.
A Ford pickup with a 460 engine (dual exhaust, and all the goodies) just to get to the grocery store... :msp_scared:
A MS880 with a 5 foot bar.... here in colorado?? (seen it in person)... :msp_scared:
A 60 inch tv screen... Just to watch a football game.... :jester:

Okay that last one is justifiable (depending on who is playing).

A Log splitter with 5000 psi of hydraulic pressure? The points have already been made against such a design, that a engineer should comprehend. This forum has seen splitters from Mild to Wild. And from really practical to extremely dangerous contraptions for assisted suicide.

Your BBQ isn't big enough... Big Johns Grills & Rotisseries 6SDG 6-ft Single Door Charcoal Grill

 

[Josh A]

Good Feed Back!

Hahaha.....as I expected this one got a good conversation going and I enjoyed reading all the comments particularly Leon's. :msp_biggrin: I worked northern PA / southern NY for awhile and the drilling language is completely different.

As to why I want to build a splitter? I know there are many with the bugs already worked out for me that I can buy retail however my objective is to learn hydraulics, specifically hydraulic pumps, piping, connections, etc from a "hands on perspective" so I can troubleshoot rig issues at work faster.

As to the safety aspect I can appreciate the comments as I routinely work with 5,000 to 15,000 psi daily 14 days out of 28. Nothing makes your butt pucker up like standing on iron trying to roll a triplex over one more quarter of a stroke to get the test pressure from 14,800 psi to 15,000 psi! In the end it comes down to 3 facts...do you have good quality people running good quality equipment cause a bull plug blowing at 300 psi will kill you just as fast as one blowing at 3,000 psi. It's all irrelevant pretty quickly.

That being said why did I pick 5,000 psi? Everybody is running 3K equipment so I figured if I am going to do this I figured go big (different) or go home for a true learning experience. When I started looking at it seemed apparent that the pump is the limitation. I can source all the hP and trailer frames I need from my uncles lawn mower / tractor dealership, hydraulic hoses from my work vendors at a reasonable cost (I just bought 100 ft of 10K hoses and fittings last hitch for example), and "scrap" steel is easily had. Now if I can't find a 5K 2 stage pump at a reasonable cost I agree...I'll drop back to a 3K high flow design and go from there.

Honestly my biggest issues will the welding. I got a buddy that will do it but its a 1.5 hour drive. To bad I can't build it at work like it could be done several years back.....I've seen some beautiful stainless steel pits built with "scrap" metal. :rolleyes2:

Josh

 

[Hddnis]

I don't think you'll find a 5k psi two stage pump readily available. You might look for a tandem pumps rated to 5k psi and then work out the two stage valves on your own. Another option would be to use a variable displacement pump with a hp limiting circuit. You might be able to use a pump for a hydrostatic system as they often can develop the pressure you are looking at.

Please keep us posted on your progress.




Mr. HE

 

[Steve NW WI]

I don't think you'll find a 5k psi two stage pump readily available. You might look for a tandem pumps rated to 5k psi and then work out the two stage valves on your own. Another option would be to use a variable displacement pump with a hp limiting circuit. You might be able to use a pump for a hydrostatic system as they often can develop the pressure you are looking at.

Please keep us posted on your progress.




Mr. HE

^^^^+1

Yup, you're on your own if you go high pressure.

You will definitely do some learning that way. As I understand how a 2 stage pump works (layman's understanding), you have 2 separate pumps - a high volume, low pressure section, and a low flow, high pressure section. At low pressure, both run. When pressure increases past the setpoint of the low pressure section, it's bypassed and only the high pressure section works until pressure lowers back to the low side's cut in point.

With some knowledge and research, you could build your own high pressure 2 stage system with a pair of single stage pumps and the proper valving.

Interested in watching this if you take it forward from here.

 

[Josh A]

Patrick,

I agree with you...tried to give you a "like" but the damn hacked web site wouldn't let me! There is a lot of the bigger is better....and I admit Im guilty of it with a lot of things. My wife and I were talking about a friend tonight at dinner with a Power Stroke that has never pulled a trailer with it!

Right now my whole idea is just a back of napkin idea with a little math in my head. When I get time this weekend free at work Im going to sit down and put pencil to paper and look at the cost and technical specs. If it seems pointless from a safety, force / pressure, or cost analysis I have no issue dropping ack and punting to a 3K system.

In the end my main reason for a 5K design is that is what we use a lot at work and I feel it would benefit me most working with what I deal with on a day to day basis. Also...I live in south Texas so I don't need to split a whole lot of wood. The tractor mounted splitter I got now is more than sufficient....this is pure learning on this build.

Thanks for all the feed back. I knew I would get some honest comments so if you got anymore keep them coming.

Josh

 

[jarhead78]

If you need a cheap 5000 psi pump. I am also triing to build a log splitter with a IH combine hydrostatic pump that puts out 5000 psi @ 40 gpm at idle. What I have been told by most people is that the psi is the problem. But, have also been told once that both the psi and the 40 gpm are the problem. Already have a 7in cylinder from a compactor so I know the cylinder can handle the psi. Anyone know why the gpm would be a issue?