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I've forgotten this! (Hydraulic Motors - Relief Valves, etc)

I've forgotten this! (Hydraulic Motors - Relief Valves, etc)

I've forgotten this! (Hydraulic Motors - Relief Valves, etc)

I'm a Mech Ag -- and It's been 30 years since I studied Hydraulics -- (can't find any of my 'books' either.

Friend (Machinist) -- has built a very complicated (hydraulically) Log Saw -- He wants to cut hardwood --

Issue is that softwoods cut great - hardwoods create a 'wavy' instead of a level cut - He has his blade running as fast as the current set-up will allow and has the table moving as slow as possible hence he wanted to 'speed up' the saw -- So he increased the tire size that the Blade is mounted on. -- then he is stalling the hydraulic motor and pulling down the 29HP motor -- he has a pressure gauge plumbed between the relief valve and the flow control valve -- max pressure showing on stall is 1000 psi.

Basic hydraulic plumbing is a nightmare on this 'unit' -- 2 pumps driven from a 29 hp engine -- (both standard gear pumps) -- one is dedicated to the 'saw' -- it has a standard relief valve next to the pump then goes through a manual flow control valve (set to max) then a Hyd Cushion valve (rated at 30 gpm) then the hyd motor. -- unfortunately the unit is in a very dark shop and I couldn't get any specific identity's of the pump, nor motor -

I have a flow meter that I can plumb in - I'm thinking first thing is to see what flow/pressure I have post relief valve -- and go from there -- with two different relief's in the system (main and hyd cushion) either I think could be set 'low' -- or we have a Pump (no GPM at pressure) or - motor (incorrectly sized) issue

Am I on the right track?

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