The HPG series of hydraulic lubrication pump is controlled by a hydraulic motor. The displacement of the lubrication pump is linearly related to the hydraulic motor speed, which makes it suitable for complex and variable working conditions.Driven by a hydraulic motor and used with a control system, the pump is designed for a single-line centralized lubrication system. When lubricant should be delivered to lubrication points, the solenoid valve located at the front of the hydraulic motor is energized, and the lubrication pump begins to work. When the grease injector completes the filling operation and the pressure of the system reaches the set value, the pressure switch transmits the signal to the control unit, then the control system cuts off the power supply of the solenoid valve, and the whole system relieves pressure and enters the next lubrication cycle.