Bosch SB23 OC additional control unit (AK control technology)

Offered here are SB23 OC valves that were installed on various tractors from the manufacturers JCB, CASE, IHC, Deutz and Zetor.

The auxiliary control unit is a four-position device that can be used for double-acting and single-acting lifting cylinders. It features spool-sealed cylinder ports A and B. This means that extremely low leakage is permissible even with heavy loads. The unit has a detent position in the lifting position, which is equipped with a hydraulically automatic limit switch and releases at 180 bar. If you switch beyond the lowering position, the detented float position is activated, which is not hydraulically unlocked (consumer ports A and B are connected to the return line). The float position can be used as a detent lowering position for both double-acting and single-acting lifting cylinders. The auxiliary control unit can be switched from double-acting to single-acting and vice versa. This can also be done during operation. The valve can be mounted on the left or right thanks to a freely positionable sealing plate.

Max. operating pressure [bar]: 220
Max. return pressure [bar]: 10
Nominal flow rate [l/min]: 70
Tightening torque [Nm]: 30
Coverage: positive
Connections [mm]: M22 x 1.5
Weight [kg]: 4.26
Operating temperature [°C]: -20...+80

Bosch comparison numbers:
0 521 609 001, 0 521 609 003, 0 521 609 005, 0 521 609 009, 0 521 609 010, 0 521 609 011, 0 521 609 013, 0 521 609 014, 0 521 609 019, 0 521 609 021, 0 521 609 022, 0 521 609 043, 0 521 609 049, 0 521 609 053, 0 521 609 054, 0 521 609 062, 0 521 609 063, 0 521 609 064, 0 521 609 068, 0 521 609 069, 0 521 609 070, 0 521 609 074, 0 521 609 079, 0 521 609 080, 0 521 609 086, 0 521 609 089, 0 521 609 092, 0 521 609 093, 0 521 609 096