Abstract: A hydraulic system for a rotary implement, including an oil tank, a main pump, a control valve, and a rotary motor is provided. The oil tank is connected to an oil suction port of the main pump; an oil outlet of the main pump is connected to a P port of the control valve; a T port of the control valve is interconnected with the oil tank; and A and B ports of the control valve are connected to both ends of the rotary motor. The control valve includes a compensation valve connected to the P port and the T port, an electric proportional valve connected to the P port and the compensation valve, and an electromagnetic reversing valve connected to the compensation valve, the T port and the B port.

Abstract: Disclosed are a hydraulic control system for boom floating of an excavator and a control method thereof. In the hydraulic circuit, a main pump supplies oil to the boom cylinder through a boom reversing valve, and two working ports of the boom reversing valve are connected to a rod cavity and a rodless cavity of the boom cylinder respectively. A rod cavity floating valve and a rodless cavity floating valve are connected to an oil circuit between the rod cavity of the boom cylinder and the boom reversing valve and an oil circuit between the rodless cavity of the boom cylinder and the boom reversing valve respectively. A pilot oil pump and a handle pilot valve are arranged on the pilot oil circuit, an oil inlet of the handle pilot valve is connected to the pilot oil pump.

Abstract: The present disclosure provides a pilot proportional control valve apparatus, an automatic calibration method, engineering machinery and a storage medium, and relates to the technical field of engineering machinery, wherein the pilot proportional control valve apparatus including a hydraulic system and a controller; the hydraulic system including: a plurality of proportional pressure reducing valves, a calibration reversing valve, and a pressure sensor; the calibration reversing valve including a plurality of reversing units, an output end of each proportional pressure reducing valve being respectively connected with an input end of one corresponding reversing unit; the pressure sensor being arranged in a detection oil path; the controller performing calibration processing on the proportional pressure reducing valve according to a pilot oil detection pressure and an output pressure value of the proportional pressure reducing valve.

Abstract: The present disclosure relates to an excavator, a precise control method and system therefor, a vehicle terminal and a storage medium. The precise control method for the excavator comprises: presetting a plurality of work modes of the excavator, and an action rate and action coefficient corresponding to each working mode of the plurality of work modes; and performing work mode switching according to a handle input signal.

Abstract: A hydraulic system for a rotary implement, including an oil tank, a main pump, a control valve, and a rotary motor is provided. The oil tank is connected to an oil suction port of the main pump; an oil outlet of the main pump is connected to a P port of the control valve; a T port of the control valve is interconnected with the oil tank; and A and B ports of the control valve are connected to both ends of the rotary motor. The control valve includes a compensation valve connected to the P port and the T port, an electric proportional valve connected to the P port and the compensation valve, and an electromagnetic reversing valve connected to the compensation valve, the T port and the B port.

Abstract: The present invention relates to a relay protective device, a construction machine, a relay protection control method and apparatus, and a computer readable storage medium.

Abstract: Disclosed are a hydraulic control system for boom floating of an excavator and a control method thereof. In the hydraulic circuit, a main pump supplies oil to the boom cylinder through a boom reversing valve, and two working ports of the boom reversing valve are connected to a rod cavity and a rodless cavity of the boom cylinder respectively. A rod cavity floating valve and a rodless cavity floating valve are connected to an oil circuit between the rod cavity of the boom cylinder and the boom reversing valve and an oil circuit between the rodless cavity of the boom cylinder and the boom reversing valve respectively. A pilot oil pump and a handle pilot valve are arranged on the pilot oil circuit, an oil inlet of the handle pilot valve is connected to the pilot oil pump.

Abstract: The present disclosure provides a pilot proportional control valve apparatus, an automatic calibration method, engineering machinery and a storage medium, and relates to the technical field of engineering machinery, wherein the pilot proportional control valve apparatus including a hydraulic system and a controller; the hydraulic system including: a plurality of proportional pressure reducing valves, a calibration reversing valve, and a pressure sensor; the calibration reversing valve including a plurality of reversing units, an output end of each proportional pressure reducing valve being respectively connected with an input end of one corresponding reversing unit; the pressure sensor being arranged in a detection oil path; the controller performing calibration processing on the proportional pressure reducing valve according to a pilot oil detection pressure and an output pressure value of the proportional pressure reducing valve.

Abstract: The present invention relates to a relay protective device, a construction machine, a relay protection control method and apparatus, and a computer readable storage medium.

Abstract: Disclosed are a novel rotation control system and method for an excavator. The novel rotation control system comprises a controller, an electrical control handle, an instrument, a rotating motor, a rotating valve trim, a main pump, a first electromagnetic valve, a second electromagnetic valve, a first pilot pressure sensor, a second pilot pressure sensor, an overflow valve and a one-way valve, and further comprises a rotation sensor used for detecting whether an excavator is rotating, a regulator used for controlling the displacement of the main pump, and a temperature sensor used for monitoring the temperature of hydraulic oil in real time.