Hydraulic-crane damping system - has by=pass pipe across slewing mechanism containing throttle and RAM piston in series

摘要

The damping system is for the swinging movement of a hydraulic crane with jib slewed on a vertical axis by a double-acting system in a hydraulic circuit (58,60). The damping unit (66) contains a throttle (64) in series with a hydraulic ram (68), whose piston (70) moves freely to and fro between two end positions. This is mounted in a bypass pipe (62) across the slewing mechanism (48). There can be a second damping system in the hydraulic derricking circuit, connected to the side subjected to the pressure from the load, and comprising a hyraulic accumulator connected in series with an adjustable throttle. USE/ADVANTAGE - Damping system for crane matches damping effect to magnitude of load and jib swinging movement.