Closed center control valve on wood splitter?

[Woodtroll]

Hello folks,

I ran across two different Dirty Hands hydraulic wood splitter control valves on a surplus site. One is open center, one is closed center. It surprised me to see a closed center valve used on a wood splitter. I would have thought that open center would be preferred to limit heat buildup at the pump when the cylinder is not moving, and I thought/assumed that most two stage wood splitter pumps were positive displacement gear driven pumps.

Why would a closed center valve be used, and what type of pump would that imply? Or is the surplus pressure just dumping through a relief valve if the cylinder isn’t moving? I have some basic hydraulic and mechanical knowledge, so this is more of a curiosity question for my own education than anything else.

Thank you for any insight or thoughts.

 

[sean donato]

Closed center valves are only used with closed center systems. Typically an axial piston pump. Swash plate centers and flow drops to "zero" when pressure limit is reached. No real benefit to use a closed center system on a basic log splitter, or really even a fancy log splitter. Cost factor and complexity go through the roof for basically zero benefit. Only time I can see it being (valve) used is if you're powering the splitter off a tractor with a closed center system.

 

[Woodtroll]

Thank you, that makes sense! I think Dirty Hands made some three-point splitters for tractors as well as the gasoline stand-alones, so that would explain why they offered both. I should have thought of that myself. Thanks again for your explanation.