Hydraulic Reservoir for Logsplitter

[Smelt]

Greetings,

I'm getting the parts together to build a logsplitter. I was going to power it with my L3400, but I got a really good deal on a 11 H.P. Honda. I'd rather put the hours on the Honda instead of the L3400. Anyway, my question is this; would the hydraulic reservoir (holding 12 gal or so) of fluid ever be under pressure. If not, I thought I could use a steel box beam and weld ends, breather, inlet, outlet, etc. and then use the beam as an integral part of the trailer carriage. I plan on using a 4" x 24" cylinder, a 16 GPM pump, and a detent valve made for logsplitters. I'd appreciate your thoughts.

 

[kennyd]

The reservoir should never be under pressure, it should also be vented with a proper cap. It should also be approximately the same capacity as the rated pump GPM so your 12 gallon reservoir with 16 GPM pump should work well. There are quite a few log splitters on the market that use the frame as the reservoir.

 

[Wayne County Hose]

Sounds like a good plan. Don't forget the filter.

 

[Smelt]

Thanks for the info kennyd. I'm sort of trying to figure out how to do it with just a tiny bit of hydraulic knowledge...I don't want to blow myself up or anything...BOOM!

 

[Treemonkey1000]

I have a 34 ton splitter and it uses a 11hp Honda. The tank is in the frame for the wheel axles. You might go by a lawn and garden place that sells them or a rental place and check them out. They are fairly simple. If you do build one try to get it so that it will split horizontal or vertical. The log rounds that I have to split are way to heavy to try and roll up to do horizontal splits. Like the other guys said there shouldn't be any pressure in the supply tank. It should be vented for thermal expansion of the fluid.
Jim

 

[JuHaa]

Hi!

First I have to say that I'm from finland and my english isn't very good, so please understand.

I made also hydraulic log splitter a couple of years ago. Oil flow comes from mf-365. Now I'm putting a hydraulic pump and reservoir on that splitter. Then I can use it with mf-135.

My question is: How much volyme this reservoir should have? I planned something about 40 litres. It's about 12 gallons?? Cylinder is 80mm (a little bit over 3").

There are a few of pictures of my projekt:

Picasa Web Albums - Juha - Puun halkaisija

 

[Wayne County Hose]

Hello JuHaa and welcome to TBN. Your english is just fine.

Funny thing, I was just doing some reading last night on hyd reservoirs. They stated the importance of having a large enough capacity for the fluid to rid itself of microscopic air bubbles. The fluid actually needed to rest for a little while before being cycled again. Air bubbles in your oil, too tiny to see, make the oil hotter. They also said that when the bubbles leave the system, they also carry comtaminants out with them. I've also been doing some reading on some very high quality breathers. Through testing, they found that most contaminants enter a hyd system thru the breather. There is a facility here in the states that has not changed any oil in their equipment since 1995, they just top off what gets lost due to evaporation. They accomplished this thru filtering and high quality breathers. Interesting stuff.

Your reservoir capacity sounds like it's big enough. How many gpm is your pump?

 

[JuHaa]

Hydraulic staff is quit intresting.

I have also read something about hydraulic reservoirs. I'm studying mechanical engineering and we have had one course about hydraulics. And there are said that reservoir should be 3 times that how much pump cycles oil in minute. And its because just those air bubles.

But it haven't to have to be that big if system can rest a while during when it's used. For example in logsplitter cylinder doesn't go whole time back and forth.

We have firewood processor with hydraulic splitting (japa 600) and there is only 20 litres reservoir. But it's too small.

My pump is about 9-14gpm (30-40litres). Depending how much there is rpm in PTO. Have I understood right that gpm = gallons per minute??

Oke, now reservoir is ready. Volyme about 40 litres. If oil gets hot, I make bigger reservoir. Filter and breather is on the top of reservoir.
Picasa Web Albums - Juha - Puun halkaisija

 

[B2400]

I built a splitter with a 16gpm pump, 5x24 cyl and use a 9 gallon reservoir salvaged from an old skid steer. The reservoir is baffled and I believe this helps with aeration. The other thing to remember...oil temps may seem high by feel but can run approx 100F above ambient temp when working the unit hard. This seems to be the norm for tractor hydraulics.

 

[Farmerford]

JuHaa:

Your logsplitter is a clever design. It took me a few minutes to understand how the extensions at each end of the ram shift the valve. If I understand it correctly, the vee shaped main support holds the wood centered so you don't have to. And the cylinder, once started, moves the ram foward all the way to the end knife before it trips the valve to neutral.

One question: is there any mechanism to keep the ram from jumping out of the vee slot? Seems like its weight would keep it in the groove in most cases. But what if the end of the wood is cut at an angle so that the top of the ram strikes the wood before the bottom of the ram strikes? Does the ram tend to rise up out of the groove?

Welcome to TBN and congratulations on your clever design.