R901174601 Bosch Rexroth Directional seat valve

Type M-Z4SEH 10 … General The SEH type directional valves are directional seat valves with electro-hydraulic actuation. Here, depending on the order version, it can be switched or switched off via one or two channels. The directional valve basically consists of a housing (1), a pilot operated check valve installation set (2), pilot control valve (3) as well as blanking plugs for the pilot oil supply. The valve is free-flowing, independent from the direction, and is opened or blocked in a leakage-free manner depending on the switching position of the pilot control valve and the pressure ratio in the main valve. Function The function of the valve is pressure-dependent. The force of the compression spring (4) as well as the force generated by pressure in the control chamber (5) take effect in the closing direction, while the forces generated by pressure in the channels A and B take effect in the opening direction of the valve spool (6) with spool sealing. The direction of action of the resulting force from the opening and closing forces determines the switching position of the check valve installation sets (2). The pilot pressure application and/or unloading is implemented via the pilot control valve (3) depending on the selected pilot oil supply. The pilot oil supply is implemented via the respective highest pressure from the channels A, B, P or X and is secured via a check valve (7). Notice! For nozzles and plug fitting, please refer to the project planning information.

➀	component side
➁	plate side

Version “XY” The pilot oil supply is implemented externally - via the X channel - from a separate circuit. The pilot oil return is implemented externally via the Y channel into the tank. Version “PY” The pilot oil supply is implementedinternally from the P channel of the main valve. The pilot oil return is implemented externally via the Y channel into the tank. In the subplate, port X is closed. Version “PT” The pilot oil supply is implemented internally from the P channel of the main valve. The pilot oil return is implemented internally via the T channel into the tank. In the subplate, ports X and Y are closed. Version “XT” The pilot oil supply is implemented externally - via channel X - from a separate circuit. The pilot oil supply is implemented internally - via channel T - into the tank. In the subplate, port Y is closed.

	Connection	Internal	External	Port in subplate closed
Version “XY"	Pilot oil supply	X	–	✔	–
Pilot oil return	Y	–	✔
Version “PY”	Pilot oil supply	P	✔	–	X
Pilot oil return	Y	–	✔
Version “PT”	Pilot oil supply	P	✔	–	X and Y
Pilot oil return	T	✔	–
Version “XT”	Pilot oil supply	X	–	✔	Y
Pilot oil return	T	✔	–