If the platform cannot rotate in one direction, it is generally caused by the pressure imbalance of the corresponding non rotating secondary overflow valve. At this time, the corresponding secondary overflow valve that cannot rotate can be adjusted and the cap can be loosened. Install a pressure gauge in the rotary oil circuit and let the driver operate the pilot handle to control the rotation. While adjusting the secondary overflow valve left and right, the maintenance personnel can observe whether the displayed value of the pressure gauge changes. If there is any change, the pressure value can be adjusted to the design overflow value; If there is no change, it may be caused by the following reasons:
(1) The tightening torque of the corresponding non rotating secondary overflow valve is not enough; Further tightening is required.
(2) Failure of secondary overflow valve; Replace and repair the secondary overflow valve.
(3) Corresponding to the secondary overflow valve shell that cannot rotate, there is sand hole and oil string; Shells with sand holes should be replaced.
