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Old 01-10-2016, 03:14 PM
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DADSGARAGE DADSGARAGE is offline
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Default Re: PC1800 Front Shovel (1/12)

Quote:
Originally Posted by Lil Giants View Post
So what pressure are you currently running at?

So you can't feather two valves together at all for simultaneous movement?

I don't fully understand the open/closed concept, but I'm pretty sure these german made rotary valves are open center, as there is two return lines off one side of the valve; one goes through prv & the other direct to tank. Precise movement of the tx & I can get all 3 valves to work together.
The PRV is set at about 275psi, the operating pressure was about 210 PSI

Yes two valves can be used together but the speed of both functions changes as well as the pressure, I can understand the pressure change but flow should remain constant no matter what the pressure is.....a positive displacement pump (gear pump) that delivers say 2cc per revolution should always deliver that amount of oil no matter what load is on the system,what will change is the pressure and the speed the oil needs to travel through the system....

In an open center valve all the flow from the pump is allowed to flow "freely" back to the tank when the spool valves are in the neutral or center position...so my thinking was that it would be a good way of eliminating the use of an ESC on the pump to gain some battery run time, the pump would always be running at a constant RPM and would take less power to just keep moving the oil in the system unrestricted when no function is being used, instead of always having a load on the pump and motor when using a closed center valve that needs a way of allowing the flow to get back to the tank using some type of unloading valve....but a closed center valve system always maintains a constant pressure in the system which is set buy the unloader valve or PRV, the open center has almost zero pressure in the neutral position because there simply is no load or restrictions in the system which is good in one way and bad in other ways.....
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