electric petrol pump designed a safety valve

The working principle of the electric petrol pump is the same as that of the electric water pump, and the corresponding oil pump device is driven by the motor, so as to continuously feed the fuel oil to the fuel system. To know that the fuel system must maintain a certain pressure, the only way to ensure that the fuel injection device fuel spray better, more easy to burn.
filling station pump ,In order to prevent the electric fuel pump out of the port side of the pressure is too high, but also designed a safety valve, so that once the fuel pump fuel pressure is too high, the safety valve will open, so that the pressure of high fuel back to the fuel tank.