WEH Electro Hydraulic Rexroth Valves with Directional Control

WEH Electro Hydraulic Rexroth Valves with Directional Control
 
Directional spool valve type WEH electro-hydraulically operated
WEH32 electro-hydraulic directional control valve
Directional spool valves are used to conrol the start, stop and direction of fluid flow and thus the direction of movement or holding position ( cylinder or hydraulic motor ) is determind. The valves can be installed in hydraulic circuit in any position together with a subplate.
The connecting surfaces are sealed with O-rings that are included with the valve.
 
DESCRIPTION OF OPERATION
 

 
The directional valve is switched by changing position of the control spool 2 which moving along its axis separates or connects ports A, B, P or T in the housing 1.
Pressure supplied to one spring chamber 6 via the pilot valve 4 acts on the main spool surface and thus the main spool is shifted from its neutral position.
The main control spool is held in centre position by the spring 4 or hydraulically that is by fluid pressure affecting( via the pilot valve ) the both spool surfaces.
Centering sleeve 7 serves centering function.
The pilot valve is electrically operated by the solenoids 5, which may be equipped with the emergency button 8. The optional emergency button allows the operation of the pilot
valve without energisation subject to the pilot fluid pressure being at disposal.
The directional valve may be provided with the pilot choke adjustment 9.
 

 

TECHNICAL DATA

 Maximum operating pressure
- in ports A, B, P                                                35 MPa for H-4WEH 32, 28 MPa for 4WEH 32
- in port T                                                                            25 MPa
pilot fluid return Y = external
pilot fluid return Y = internal
( 3-position valve spring centered, 2-position valve)     16 MPa
internal pilot fluid return
( 3-position valve hydraulically centered )                        no

Minimum pilot pressure
pilot fluid supply X = external
pilot fluid supply X = internal
three-position directional valve                                                                      pst = 0.8 MPa
two-position directional valve spring centered                                            pst = 1.0 MPa
two-position directional valve hydraulically centered                                 pst = 0.5MPa
pilot fluid supply X = internal
for spool types G, H, F, S, T ( via pre-load valve or by suitable
high flow rate )

Maximum pilot pressure                                                                                 25Mpa

Electrical connections :