1. Conditions of use

It is used in the electric ring-type centralized lubrication system to send the grease output from the pump to the two main oil supply pipes alternately. The direction is reversed directly by the pressure control valve at the end of the oil supply main pipe. The set pressure of the reversal can be easily adjusted. The reversing valve has a simple structure and reliable action.

4. Working principle

The picture on the right is a schematic diagram of the working principle of a hydraulic reversing valve. In the picture, ports T1 to 4 are connected to the same outlet to connect to the oil reservoir.

The grease output from the position 1 pump is sent from the oil inlet S through the passage formed by the main slide valve MP to the oil supply main pipe L1 (pipeline I), and pressurizes the main slide valve through the passage formed by the pilot slide valve Pp. left end. The oil supply main pipe L2 is open to the oil reservoir through the T1 port.

The end of the oil supply main pipe L1 is connected to the oil return port R1. When the pressure at the end exceeds the set pressure, the pilot slide valve is pushed to the right.

Position 2 pilot spool P p moves to the right, the left cavity of the main spool M p opens to the oil reservoir through the T3 port, and the pump outputDry thin oil lubricationGrease pressurizes the right end of the main slide valve and pushes it to the left. The contact on the indicator rod connected to the main slide valve hits the travel switch LS and sends a signal to the electric control cabinet to stop the pump.

At position 3, the main slide valve M p moves to the left, completing the reversing action. The pump works again and the grease output is sent to the oil supply main pipe L2 (pipeline II) through the passage formed by the main slide valve. The oil supply main pipe L1 passes through T2. The port is open to the oil reservoir.

6. Instructions for use

The YH F-L1 valve is matched with a pump with a flow rate of 585ml/min and is installed on the base plate. YH F-L2 type valve is matched with pumps with flow rates of 60 and 195ml/min and is installed on the pump body.

YHF-L1 type valve adjustment screw is turned clockwise to increase the set pressure and left-handed to decrease it. YHF-L2 type valve, turn right to adjust the set pressure to lower, and turn left to increase the set pressure.

When removing the YHL-L2 valve from the pump body and removing the cover of the YHF-L1 valve, the adjusting screw should be completely loosened first.