ENGINE AR 2147182 - Caterpillar

Illustration 1 g03664642
Medium Pressure
(1) Oil cooler
(2) Motor for rotation
(3) Line relief valves
(4) Auxiliary control valve
(5) Main relief valve
(6) Extend solenoid valve "A3"
(7) Retract solenoid valve "A3"
(8) Main control valve
(9) Pilot manifold
(10) Solenoid valve for hydraulic lock
(11) Pilot pump
(12) Idler pump
(13) Drive pump
(14) Auxiliary pump
(15) Hydraulic tank Medium pressure is designed to provide oil to the work tool for tool rotation. An attachment valve is used to control the oil flow. This valve is shifted with proportional reducing valves that allow the operator complete electronic control over the tool rotation. An auxiliary pump is used to supply oil flow for medium pressure. A typical example of a work tool that will use medium pressure is a shear.Reference: Refer to Testing and Adjusting, "Work Tool Parameter - Program" for the tool control system to change the settings for work tool operation.Reference: Refer to Testing and Adjusting, "Medium Pressure: Default Value of Work Tool Parameters" for the Tool Control System to reference the factory settings.
Table 1
Operation Lever List
Control Extension Retraction
Left Joystick Thumb Wheel Push Forward Push Backward Attachment Valve Extended
Illustration 2 g03664775
Attachment valve extended
(2) Motor for rotation
(3) Line relief valves
(4) Auxiliary control valve
(5) Main relief valve
(6) Extend solenoid valve "A3"
(11) Pilot pump
(12) Idler pump
(13) Drive pump
(14) Auxiliary pump When the device for activation is operated in the extend position, proportional reducing valve (6) receives a modulated signal from the machine ECM. Proportional reducing valve (6) allows pilot oil to flow to attachment control valve (4). This shifts attachment control valve (4) allowing medium pressure oil from auxiliary pump (14) to hydraulic rotator motor (2).Oil returning from the rotator motor flows through attachment control valve (4), oil cooler and back to the hydraulic tank.The working pressure for rotation is limited by the main relief valve (5).Attachment Valve Retracted
Illustration 3 g03664825
Attachment valve retracted
(2) Motor for rotation
(3) Line relief valves
(4) Auxiliary control valve
(5) Main relief valve
(7) Retract solenoid valve "A3"
(11) Pilot pump
(12) Idler pump
(13) Drive pump
(14) Auxiliary pump When the device for activation is operated in the retract position, proportional reducing valve (7) receives a modulated signal from the machine ECM. Proportional reducing valve (7) allows pilot oil to flow to attachment control valve (4). This shifts attachment control valve (4) allowing medium pressure oil from the auxiliary pump (14) to hydraulic rotator motor (2).Oil returning from the rotator motor flows through attachment control valve (4), oil cooler and back to the hydraulic tank.The working pressure for rotation is limited by the main relief valve (5).