Hydraulic control and drive system for amphibious dragline - has hydraulic swivel valve between upper draw works and under carriage

摘要

The system has a first gear box to drive variable displacement pumps. A hydraulic motor is driven by one of the hydraulic pumps, a second gear box being driven by the hydraulic motor. The second gear box is connected to drive the jackshaft of the dragline draw works, a hydraulic swivel valve being carried by the dragline draw works. Hydraulic connections extend between the swivel valve and hydraulic pumps. Operator controlled valves vary the hydraulic pressure delivered from the hydraulic pumps to the dragline draw works and to the propulsion motors.