help with hydraulics please

[..DAZ..]

I am just about ready to start building a hydraulic log splitter, but I don't know much about hydraulics. I have a Marzochi ALP-2 pump with the following specs
Displacement 4.5 to 35.2 cc/rev
Max. Continuous Pressure 250 bar
Max. Intermittent Pressure 270 bar
Max. Peak Pressure 290 bar
Max. Speed 4000 rpm
(is this a variable displacement pump?) full number is ALP2-S-13-SO.
I have a couple of different engines I can choose from, all the metal work, tank,an axle with wheels so I can tow it about, and a suitable ram. All of which has been scrounged, begged, borrowed or stolen (only kidding about the stolen)
What are the very basic things I need to get my hands on? I know I am going to need hoses and a spool valve. Do I need a limit switch to stop the ram when it reaches full stroke? How does the ram go backwards? (is that aslo controlled by the spool valve. I just want this to be as basic as possible, it doesn't need to be all singing all dancing..................it just has to work and split logs. I already have some plans sketched out so it can work horizontally or vertically.
Any help would be very much appreciated.
thanks
daz

 

[paulmowers]

Hi

Your spool valve assembly should have a return pipe back to the tank so when youre not using the pressure it is returned to the tank, also it should have a pressure relief valve so you don't burst pipes or damage the pump.

The way the ram returns will depend on wether the spool valve and the ram are single acting or double acting, if they are both d/a then you will have two pipes from the spool valve to the ram, one goes on the bottom to push the ram out, the other on the top of the ram, to push it back in. If either are only s/a, then you will need to have a large spring to pull the ram back in.

Thats the basics, I,m no expert by any means, but having restored a mcconnel PA6 I have a basic grounding in how it all works.

paul

 

[..DAZ..]

I know it is a D/A ram, so I really need to find a D/A spool valve. I might have one from a manual forklift, battery operated walk behind type thing. Might do the job, I am just waiting to find out if I can get the valve from it. thanks for the reply, much appreciated.

cheers
daz

 

[paulmowers]

hi

Just make sure it has a return pipe and pressure relief valve, not sure if it would as a lot of these electrics only run the pump motor on demand, so once lever is released the motor stops. if you are running a proper motor (engine) on the pump there will be no pressure regulator in the system.

paul

 

[zzr1200]

hi

Just make sure it has a return pipe and pressure relief valve, not sure if it would as a lot of these electrics only run the pump motor on demand, so once lever is released the motor stops. if you are running a proper motor (engine) on the pump there will be no pressure regulator in the system.

paul

Theres normally a system pressure relief valve in the valve block.

If you can aquire a valve block with 2 segments (2 levers) that way you will have the option to fit a log lift at a later dater to help lift those large rounds.

 

[..DAZ..]

My hydraulic ram is as follows
30 inch cylinder length
4 inch diameter
24 inch stroke

I have a choice of three engines so far
4hp horizontal shaft (ex water pump)
8hp horzontal shaft (ex generator) Probably tapered shaft?
8hp vertical shaft (ex lawnmower)
I am still looking around for something a bit beefier, say around 14hp. I don't know what size of engine I should be looking for, any ideas? How do I work out the amount of force I can generate? I know the pump can run from 4-30gpm. I have hopefully managed to attach a couple of photos of the same idea I am going to make
thanks
daz

 

[wyn]

There is one on this page that has a 6hp engine. and the 4" ram gives 22 tonnes.

The 8hp engines seem like they should be somewhere near.

 

[HydraulicBerty]

Anyone needs any help hydraulically i am now retired and have loads of free time on my hands and will gladly give free information.
*MOD EDIT - HYDRAULIC BERTIE IS MANAGING DIRECTOR OF THE COMPANY IN THE LINK* Send me any queries you have glad to help you youngsters out there !!!

 

[..DAZ..]

Hi and welcome, but you may live to regret that offer, I have so many questions to bombard you with you are going to be sick of me :-) I haven't quite got round to starting it yet but I just about have all the bits I need to start on my splitter. I am just practicing my stick welding so I can weld outside in the wind. I will be in touch shortly!

cheers

 

[Baloo]

theres a good forum here for hydraulics
http://www.hydraulicinnovations.com/forum/index.php?

theres all sorts of stuff from hydraulic drive motor bikes and quads to hydrostatic boats
bound to be a log splitter there somewhere,

 

[Jake]

very basic but hope it helps

 

[cookie munsta]

dosen't appear to be any pressure/ relief valves in the plans, it may be harder to control pressure without them. controlling fluid power would be more economical.

 

[cookie munsta]

unless my maths is up the creek and it probably is your pump hooked up to the hydraulic ram is good for 20.3 long ton, on the continous rating. 250bar x14.5 = 3625psi. force (lbs.)= pressure (psi) x area (in2). 3625psi acting on 4" diameter(4x4x.7854=12.56"2)= 20.3 ton........... maybe . hope it right, if so hope it help.