R900781634 Bosch Rexroth Pressure relief valve

Valves of type DB are pilot-operated pressure limitation valves. They serve to limit the operating pressure and mainly consist of the main valve (1) with main spool insert (3), the pilot control valve (2) and the closing plate (16). The pressure in channel P acts on the main spool (3). Simultaneously, the pressure is applied via the control lines (6) and (7), which are equipped with nozzles (4) and (5), to the spring-loaded side of the main spool (3) and to the ball (8) in the pilot control valve (2). If the pressure in channel P is increased due to the value which is set at the spring (9), the ball (8) opens against the spring (9). The signal for this is sent internally via the control lines (10) and (6) from channel P. The hydraulic fluid on the spring-loaded side of the main spool (3) now flows via the control line (7), nozzle bore (11) and ball (8) in the spring chamber (12). From here, it is passed on to the container internally with type DB...–... via control line (13) or externally with type DB...Y... via control line (14). Due to nozzles (4) and (5), there is a pressure drop at the main spool (3). The connection from channel P to channel T is free. Now, the hydraulic fluid flows from channel P to channel T while the set operating pressure is maintained. Via port "X" (15), the pressure relief valve can be relieved or switched to a different pressure (second pressure rating). Type DB 10…XC… See also "General information" in chapter "Technical data". Notice: With the attachment of an additional directional spool valve type 3WE 6…, the valve can be extended for solenoid-actuated unloading (see chapter "Project planning information", "Solenoid-actuated unloading").