Relief set-pressure adjustment system

Abstract

Problem: In a hydraulic system in which a manual line relief valve that adjusts the relief setting pressure is arranged in the line relief oil path formed by branching from the actuator line from the control valve to the hydraulic actuator, the relief setting pressure adjustment operation of the line relief valve can be performed independently with good accuracy. Solution: A controllerfor controlling a perform of a relief setting pressure adjustment operation of a line relief valveis provided with a pump flow control means that controls the pump flow rate during the relief setting pressure adjustment operation, an instruction command output meansthat instructs a perform of the relief setting pressure adjustment operation by a manual operation, and a notification command output meansthat notifies that the pump pressure detected by a pressure sensorduring the relief setting pressure adjustment operation is within a predetermined range of the target relief setting pressure.