GEAR-PUMP DRIVE 1725514 - Caterpillar

Illustration 1 g01350580
(1) Stick drift reduction valve (2) Main control valve (3) Boom drift reduction valve (5) Main relief valve (7) Stick cylinder (8) Boom cylinders (11) Reducing valve (boom priority mode or swing priority mode) (12) Solenoid valve (travel speed) (13) Solenoid valve (swing brake) (14) Valve (15) Solenoid valve (hydraulic lockout) (16) Pilot oil manifold (17) Accumulator (18) Solenoid valve (heavy lift) (20) Pressure sensor (idler pump) (22) Bucket cylinder (23) Pilot control valve (travel) (24) Idler pump (25) Drive pump (26) Pilot pump (27) Proportional reducing valve (power shift pressure) (28) Pressure switch (left travel) (29) Pressure switch (right travel) (30) Left travel motor (31) Right travel motor (32) Swing motor (33) Pilot relief valve (34) Pilot filter (35) Pressure sensor (drive pump) (36) Drain filter (37) Pilot control valve (swing and stick) (38) Pilot control valve (boom and heel) (39) Pilot control valve (straight travel) (40) Swivel (41) Slow return check valve (42) Bypass check valve (43) Hydraulic oil cooler (44) Return filter (45) Hydraulic tank (46) Solenoid valve (fan control) (47) Pressure switchHydraulic Pump Flow and Pressure Control System
Illustration 2 g01251149
Pump compartment (24) idler pump (25) Drive pump (26) Pilot pump (27) Proportional reducing valve (power shift pressure) (56) Delivery line (drive pump) (57) Delivery line (idler pump)This machine is driven and controlled by the following systems:
The main hydraulic system controls the cylinders, the travel motors, and the swing motor.
The pilot hydraulic system supplies oil to the main pumps, the main control valve, the swing brake, the travel motors, and the cooling fan.
The electronic control system controls the outputs of the engine and pump.The main hydraulic system delivers oil flow from drive pump (25) and idler pump (24) in order to control the following components: bucket cylinder (22) , stick cylinder (7) , boom cylinders (8) , right travel motor (31) , left travel motor (30) and swing motor (32) .
Illustration 3 g01253215
Main control valve (5) Main relief valve (48) Right control valve body (49) Left control valve bodyDrive pump (25) and idler pump (24) are variable displacement piston pumps. The performance of both pumps is equal.Drive pump (25) is directly connected to the engine by a flexible coupling. The drive pump delivers oil to the right control valve body (48) of the main control valve. Idler pump (24) is mechanically connected to the drive pump through gears. The idler pump delivers oil to the left control valve body (49) of the main control valve. Gear type pilot pump (26) supplies oil to the pilot hydraulic system. Gear type pilot pump (26) is directly connected to drive pump (25) by a coupling. All engine output is used to drive these three pumps.As the load pressure increases during working conditions, the main pumps increase the delivery pressure and the pumps decrease the flow rate. The hydraulic horsepower remains constant even though the delivery pressure and the flow rates change. The hydraulic horsepower is approximately identical to the engine horsepower.When no work is being performed, pump oil