Wood splitter hydraulic question?

[Leejohn]

Sounds like to me his valve is not returning to center, check springs.

 

[Tx Jim]

RodRocket
I ask you same question I asked Dave M7040. Do you know what time frame(year) the concept of power beyond was introduced? I sure don't remember PBY being in use in use 40 or 50 yrs ago.
Thanks, Jim

 

[Dave M7040]

I was afraid of that. I am getting a 2 valve block but also had read numerous accounts of how it worked fine.

Dave I believe you. But it doesn’t seem like the valve itself would have a lesser pressure rating on the Out port. The pump is designed to put out 2500 psi. I see where the OUT fitting and Line to tank is rated only for tank pressures but I installed the nipple between in and out as a 6000 psi hydraulic fitting.
Are you positive on that? You’ve given me great advice over the years so I trust you completely but don’t see how.

I was afraid of that. I am getting a 2 valve block but also had read numerous accounts of how it worked fine.

Dave I believe you. But it doesn’t seem like the valve itself would have a lesser pressure rating on the Out port. The pump is designed to put out 2500 psi. I see where the OUT fitting and Line to tank is rated only for tank pressures but I installed the nipple between in and out as a 6000 psi hydraulic fitting.
Are you positive on that? You’ve given me great advice over the years so I trust you completely but don’t see how.

I regret that my advice is correct especially with the valves you are working with.

I looked over the spec's for the valve you posted. The spec's are even worse than I expected with a max tank port pressure of 150 psi. Normally I see 450 psi as a valve's tank port spec..

When your second valve controlled cylinder hits the end of its stroke and the pressure spikes, your fist valve may just split,

Hydraulic oil shooting out small cracks is very dangerous and can be injected right thru your skin.

Consider putting one of your two valves on the shelf waiting for another project and buy a valve which can have PB. You do not need a valve rated for 25 gpm.

In answer to the question when did PB first appear. I do not know. In my case what has happened is that my knowledge/experience has grown.
Further, engineering design practices are much more refined and valves are able to be designed just strong enough to meet published spec's.

In the 1960's all products were built with high safety factors as this was cheaper than spending countless design hours pushing the valve design to the limit.

Now weight is a big consideration and if a few ounces can be shaved off a product, that will drive the design.

Dave M7040

 

[LD1]

Alot of older tractors had to add a pump on the front of the crank for a loader. Therefore the loader valve was the only valve in that circuit.

Modern stuff is different and built with a loader in mind from the get go. Not as an afterthought.

That in combination with most older deeres being closed center.

 

[Fxfymn413]

And a check valve in log lift plumbing would compensate for the gravity drop.

It is a double acting cylinder so a check valve will keep it from working since oil must return to the valve from the non-pressurized side of the cylinder.