The role of liquid ring pump pressure regulating hole is to prevent under-compression and over-compression, it must be set at the pressure regulating valve check valve, automatically locked when compression is insufficient, automatically open when over compression to avoid excessive power consumption. However, when the check valve is not properly designed or the material is not good lead to the check valve failure or damage, the pressure regulating hole not only does not work, but will have adverse consequences. When the pump is working at high vacuum or extreme pressure, less suction gas will occur in the compression section compression is insufficient, the pressure of the liquid outlet will never shut off the pressure back to high-speed return hole, causing a great impact, resulting in serious hydraulic Losses, resulting in a sharp increase in power consumption, pumping speed also has a certain impact. When the inhalation of a lot of gas, and pressure regulating valve can not open the valve, it will cause over-compression, resulting in increased power consumption, but also affect the pumping speed.