Hydralic spool valves

[STVV]

Hello
I am trying to learn more about hydraulic spool valve center conditions. I am trying to find out what is the intended purpose for using a float type center condition spool valve.

 

[dbaird]

A "float center" spool has both cylinder ports vented to each other and to exhaust, with inlet pressure blocked, in center position. This relieves pressure block on both sides of the cylinder position, alowing piston rod to be moved manually, or to be freely pushed and pulled by a moving member of the machine to which the cylinder is attached. This "floating" action is occasionally used on both air and hydraulic systems.

David Baird
mrbaird@hotmail.com
Sr Controls Designer
EET degree.
Journeyman Electrician.

 

[budt]

Also, a FLoat Center is often used with a hydraulic motor so it can coast to a stop to eliminate shock when stopping rotation.

It is imperetive when using Pilot OPerated Check Valves or Counter Balance Valves to eliminate pressure when the action of a cylinder or other positively seald device must be stopped and held in position and the pump supply must be available for other circuits.


Bud Trinkel CFPE
HYDRA-PNEU CONSULTING, INC.
fluidpower1 @ hotmail.com

http://www.fluidpower1.us