BOLT 8F6978 - Caterpillar

Illustration 1 g02786282
Swing Hydraulic System
(1) Steering valve
(2) Travel motor and transmission
(3) Boom cylinders
(4) Stick cylinder
(5) Bucket cylinder
(6) Main control valve group
(7) Fan motor
(8) Swing motor
(9) Fan pump
(10) Swing pump group
(11) Main pump group
(12) Engine
(13) Brake pilot steering pump
(14) Brake valve group
(15) Pilot manifold with transmission shift
(16) Pilot control valves The swing system consists of a variable displacement swing pump (10) with a charge pump and swing motor (8). A Pilot valve directs pilot oil to the swing pump control valve. The swing pump proportional relief valve, mounted in the pilot manifold (15), limits the maximum pilot pressure to the actuator piston in the swing pump.This maximum pressure varies according to the power mode that is selected. When a power mode is selected, the setting of the proportional pilot limiting solenoid valve remains constant.