Rotary crane arm system`s dead weight compensating method, involves compensating change of load caused on arm adjusting device by dead weight of arm system of crane during change of unloading by hydraulic system connected with arm system

摘要

The method involves compensating change of load caused on an arm adjusting device by the dead weight of an arm system of a rotary crane during change of unloading by a hydraulic system that is connected with the arm system by a rope (8). The pressure in the hydraulic system is controlled by a hydraulic pump. A minimum pressure is maintained in the hydraulic system during minimum unloading of the arm system. An independent claim is also included for a device for dead weight compensation of an arm system of rotary cranes.