# Hydraulic Splitter Tank Size ?????



## bearings (Dec 17, 2009)

Ok Here goes. I have been searching for what size of a hyd. tank my splitter will need. Here is what i am going to use. 4x30in cylinder with a 2in rod. I have a 10hp B&S Engine and want to run a 16gpm pump. Now with that info out i would like to know what is the ideal size hyd. tank size in gallons. Every time i find some info it says to put this huge tank on there that will cost $100 to fill up. My fathers didier splitter that he has had for the last 30 years has like a 1.5 gal tank on there. It has a slower pump but has the same size cylinder. Can i get buy with a 3 gallon tank? I was thinking about a tank as my axle but i only have a 4x6 tube. What size and a brief why? Thanks


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## ray benson (Dec 17, 2009)

I had a 5 or 6 gallon on my splitter,16gpm 4"x24" cyl. Oil would heat up and limit my splitting time. Upgraded to a beer half keg which is 15.5 gallons. Cost at the recycle center for a stainless steel keg - $15.


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## bearings (Dec 17, 2009)

So what happens when the oil heats up it? It gets thinner so you have less power? Thanks for letting me know that i dont want to buy things that wont be right. How much does it change with the speed?


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## ray benson (Dec 17, 2009)

Max temp of oil is around 150°, small tank you would run over that pretty quickly. Hoses and cylinders life is affected by higher temps.
Here is a good post by Kevin http://www.arboristsite.com/showthread.php?p=1516626&highlight=logsplitter+tank+size#post1516626


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## mga (Dec 17, 2009)

ray benson said:


> I had a 5 or 6 gallon on my splitter,16gpm 4"x24" cyl. Oil would heat up and limit my splitting time. Upgraded to a beer half keg which is 15.5 gallons. Cost at the recycle center for a stainless steel keg - $15.



that's about right. i have an 18 gallon tank, figure in the lines and the cylinder and i have probably close to 20 gallons of oil. filling it was kinda expensive.


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## mga (Dec 17, 2009)

bearings said:


> Ok Here goes. I have been searching for what size of a hyd. tank my splitter will need. Here is what i am going to use. 4x30in cylinder with a 2in rod. I have a 10hp B&S Engine and want to run a 16gpm pump. Now with that info out i would like to know what is the ideal size hyd. tank size in gallons. Every time i find some info it says to put this huge tank on there that will cost $100 to fill up. My fathers didier splitter that he has had for the last 30 years has like a 1.5 gal tank on there. It has a slower pump but has the same size cylinder. Can i get buy with a 3 gallon tank? I was thinking about a tank as my axle but i only have a 4x6 tube. What size and a brief why? Thanks



usually the stuff you read on line about hydraulic systems are talking about machinery with many moving parts. you can't use the same formulas for a simple log splitter.

but, alot depends on the use of the splitter. i have an 18 gallon tank which keeps the oil pretty cool, but during hot summer days, the temps can creep up over 100 degrees. i put a temperature gauge on the inlet line and if i felt it got too hot, i would just shut it down for a while and take a break.

but, i have seen some with small tanks run all day without any problems.


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## loadthestove (Dec 17, 2009)

Has anyone tried use an oil cooler similar to a transmission cooler.If used in the return line would the pressure be to high ??


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## A.E. Metal Werx (Dec 17, 2009)

i have 9 gallons in my tank with just about the same set up. and after use for 2 hours it sits about 100 degrees. .


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## Buckethead (Dec 17, 2009)

*Rule of thumb...*

Typically, it is recommended that the size of your tank be equal the output of the pump in one minute. So, if you have a 8 gpm pump then you should have an 8 gallon tank. This allows for sufficent storage so the hydraulic oil doesn't overheat.


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## mga (Dec 18, 2009)

loadthestove said:


> Has anyone tried use an oil cooler similar to a transmission cooler.If used in the return line would the pressure be to high ??



i did on mine. i also put two 12 volt pancake fans to blow air thru it. i was bored one day and decided to try it out.


i thought i had a pic of it...guess not.

and, yea, you would only want something like that on the return line only!


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## triptester (Dec 18, 2009)

The best way to determine the tank size needed is to look up the specs for tanks used on commercially built splitters. Look at their pump gpms and the size tank they use. Next look at their tank design, long and thin tanks are usually lower capacity but put greater distance between supply and return lines.
Overall system design can contribute to heat build up. A combination of little things will cause heat build up, small hoses, too many fittings, fittings with small orifices, return line that is not fully submerged in the tank.
A properly designed splitter with a 16 gpm pump does not need more than a 10 gallon tank.


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## leon (Dec 18, 2009)

*log splitter*



bearings said:


> Ok Here goes. I have been searching for what size of a hyd. tank my splitter will need. Here is what I am going to use. 4x30in cylinder with a 2in rod. I have a 10hp B&S Engine and want to run a 16gpm pump. Now with that info out I would like to know what is the ideal size hyd. tank size in gallons. Every time I find some info it says to put this huge tank on there that will cost $100 to fill up. My fathers Didier splitter that he has had for the last 30 years has like a 1.5 gal tank on there. It has a slower pump but has the same size cylinder. Can I get buy with a 3 gallon tank? I was thinking about a tank as my axle but i only have a 4x6 tube. What size and a brief why? Thanks



====================================================================================================


Breifly if you insist:


The Didiers used a geroller pump/motor from what I rememberf which has a very low flow rate at speed 


Hydraulic oil has to stay very hot(120-150degrees to perform at its maximum efficiency for fluid power.

You need a tank big enough to allow for the surge of oil from the retraction of the cylinder rod which pushes all the oil from the cylinder barrel into the tank while still having enough hydraulic oil to feed the pump at the VERY SAME TIME and to allow the air to leave the tank without having a geyser of hot oil to burn you-which is why the small manufactured tanks have the filler caps with the air vent and screens combined. The pump suction line in the tank will quite often have a large suction strainer as well. 


Hydraulic is thin for a reason- to allow it to expand while heated and deliver more fluid energy. 


My post with hydraulic cylinder race race track diagram for check valves to get all the oil hot and keep it hot should still be on the forum here for everyones use.

The down load has a complete parts list too.


FYI you have to realise the oil is always moving and the oil moving between the valve and the cylinder takes forever to warm up to temperature, and to be at its most efficient to deliver fluid power because it is separated by the valve and the cylinder itself which behave like a steam radiator releasing the heat from the oil.

That is why I have posted the race track diagram for more efficient fluid flow to keep the oil hot and have better log splitter performance.

This is also why I use a salamander to heat the log splitter up prior to start up-it keeps you warm while you work too.

leon

opcorn:

mutual sufferer of CAD and log splitter addiction


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## ray benson (Dec 18, 2009)

5 gallon cans are about $40 Probably get it cheaper.
http://www.autozone.com/autozone/ca...ame=Oil,FluidandLubrication&_requestid=762821


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## topofthehil (Dec 18, 2009)

leon, can you point me to more information on a salamander?
I am in the process of building a hyd tank and was thinking of using a couple of water heater elements.
I welded two 1" couplings, one on each end of my tank, in hopes that I could find a heater that is threaded. I'll plug them for now.
FYI the size of a hyd tank? I have been told that, at a min, it should be the size of the pump in gallons if not 1.5 to 2 times that size.
I have a 22 gpm pump and my tank is approx. 36 gal.


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## leon (Dec 18, 2009)

*log splitter*



topofthehil said:


> leon, can you point me to more information on a salamander?
> I am in the process of building a hyd tank and was thinking of using a couple of water heater elements.
> I welded two 1" couplings, one on each end of my tank, in hopes that I could find a heater that is threaded. I'll plug them for now.
> FYI the size of a hyd tank? I have been told that, at a min, it should be the size of the pump in gallons if not 1.5 to 2 times that size.
> I have a 22 gpm pump and my tank is approx. 36 gal.



========================================================================================================================================================================================================

A kerosene or propane fired salamader space heater for open areas/wide buildings. available at farm stores like tractor supply and they are available at northern tool etc. I bought mine(kerosene fired) locally 16 years ago and I 
am able to obtain service locally which is a plus.

I have only needed a new male plug cord(due to mice chewing damage) and a new ingniter spark plug=which is specialty plug designed for these units and portable hot water generators.

A propane fired space heater will be smaller and weigh less(can be carried versus being wheeled around for the larger kerosene fired units) as the heater has no belly tank under the burner, a small propane tank with a regulator and hose can fuel it easily and the small heaters(both kerosene and propane) require 110 volts to fire them up. 

I use my generator to power the salamander and work lights typically to avoid running around with a lot of extension cords.


I hate to ask you this but did you weld a baffle in the tank with holes in the bottom of the baffle to allow the oil to rid its self of air bubbles to allow them to rise to the surface and eliminate any oil turbulance?

If it is already boxed up the pump inlet should be at the bottom and the return near the top-saying that: 

The return line must be positioned to return the oil to below the maximum oil level in the tank(to avoid making air bubbles/cavitation) so if you have 36 gallons of capacity you can have 30 gallons of oil safely stored in the tank to allow for dumping the barrel end of the cylinder when it is fully retracted and still have plenty of room for air to exit and enter the tank to allow 
un-restricted suction and expansion/oil return to tank.

Please be sure to buy the right size suction hose for the inlet side of the pump-to small a hose will create too high a vacuum and starve the inlet side of the pump and as a result the pump will create air bubbles and wear out prematurely. 

The hose used may also collapse and create even more problems.






1.The tank should always be above the pump inlet.

2. you should have a spin on oil filter on the line exiting the valves return to tank line. The placement of the filter location is up to you but if the filter housing has a mounting braket you can securely anchor it near the valve or on the side of the tank with the filter housing pointing down.

a. the return to tank line from the filter to the tank must:

Have a mild sweep or curve to allow expansion and contraction due to heat from the oil and cold temperatures.

3. The suction line coming from the tank to the pump inlet must be lower or level with bottom of the tank to avoid cavitation and oil starvation to the pump inlet.

a. the pump suction line must:

Have a mild curve or sweep to allow expansion and contraction
of the oil and avoid premature failure of the hose.

You can buy standard hose lengths(and JIC female fittings) and simply loop and restrain them with loom clamps easily as well with a piece of angle iron welded to the tank to secure the suction line and pressure line to the valve body. 

The heavy woven hose protector tubes are a godsend to prevent injury from a hose rupture or pin hole leak which can cause injury.
4. The size of your oil tank is fine with no issues.

5.Using hot water heater elements is not a good idea due to corrosion, and boiling of the oil/ shorting out the elements in the oil bath and the electrocution hazard, and needing 220 volts direct and split at the elements.


a. The salamander space heater is less work and warms everything up quickly 10-15 minutes at the most which in turn warms your gas engine, valve body, cylinder, pump and hoses.


leon


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## triptester (Dec 18, 2009)

topofthehil said:


> leon, can you point me to more information on a salamander?
> I am in the process of building a hyd tank and was thinking of using a couple of water heater elements.
> I welded two 1" couplings, one on each end of my tank, in hopes that I could find a heater that is threaded. I'll plug them for now.
> FYI the size of a hyd tank? I have been told that, at a min, it should be the size of the pump in gallons if not 1.5 to 2 times that size.
> I have a 22 gpm pump and my tank is approx. 36 gal.



A 36 gallon tank on a splitter with a 22gpm pump is way overkill. The 1.5 to 2 times the pump capacity is for industrial applications with continuous use at high ambient temperatures. That large of a tank may cause more harm than good especially in a northern climate. The cost of a fluid change and filter could exceed $200.00. The weight of the fluid and extra tank material could total 400 pounds making the splitter that much harder to move around.

Most splitter manufacturers use between 15 and 20 gallon tanks with a 22 gpm pump.


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## topofthehil (Dec 21, 2009)

bearing, sorry for jumping in on your thread.
I don't have the ends of the tank welded up yet, so I can still modify it.
it is a 15" dia pipe by 48" long.
after reading the comments, the first thing I will do is cut 12" off one end of the pipe (tank).
the tank will then have approx 27 gallon cap.
I will weld in a baffle. 
do commercial splitters have baffles?
does the baffle have to span the width of the tank?
I have a question about the return line to the tank.
I welded full couplings on the tank. I did not cut them in half.
so, on the inside of the tank, can I thread a 45 degree street elbow with a nipple on the end so the return oil will dump about 4" below the surface?
that way I can mount the return filter just above the surface.


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## leon (Dec 21, 2009)

*log splitter*



topofthehil said:


> bearing, sorry for jumping in on your thread.
> I don't have the ends of the tank welded up yet, so I can still modify it.
> it is a 15" dia pipe by 48" long.
> 
> ...



That should be fine as long as the return elbow is below oil level to avoid sucking air if a pin hole exists and you do not find it prior to sealing the tank.

also you need to add an 90 degree elbow with another pipe nipple to straighten out the oil flow to avoid scouring the bottom of the tank and pushing any dirt back in the oil.

The baffle will help to slow down any dirt as well in this case, the exit holes for oil flow for the baffle should be about an inch above the bottom-

you could simply cut a slot in the baffle an inch above the bottom nearly the width of the baffle to allow oil flow rather than several holes-this would allow a smoother mass oil flow.


leon


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## builder1101 (Dec 21, 2009)

bearings said:


> So what happens when the oil heats up it? It gets thinner so you have less power? Thanks for letting me know that i dont want to buy things that wont be right. How much does it change with the speed?



thinner the oil easier on the pump...and no, viscoity doesn't make it have less power, if your loosing power when it gets thin, better investigate seals & o-rings

some guys use ATF fluid.

just having the pump move oil will make heat...

if the cylinder case is getting hot enough where it starts to burn (175+), there's some serious restriction....i doubt log splitters can work hydraulics fast enough to make that kind of heat... a cat cummins turning a 50+gpm pump, that will make some heat...

personally i use whatever i can find. Drain oil from oil changes in the vehicles and equipment is my choice., especially the 5w-30 watery stuff. 35 years and still functions like day 1. i run it through cheesecloth and then coffee filters first.


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## triptester (Dec 21, 2009)

To get the most efficiency out of a baffle in a hydraulic tank place both the supply and return at the same end of the tank. Then place the baffle down the middle between the supply and return this will force the fluid to travel the full length of the tank twice. Put four 1" holes vertically near the far end of the baffle and clip the bottom corner. This clipped corner will allow fluid to move from one side of the baffle to the other with a drain plug in the bottom of the tank at the clipped end. It would also be nice to have a removable cover on the top of the tank for cleaning purposes.


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