Ejector pin formula back pressure system

The utility model relates to an ejector pin formula back pressure system belongs to conventional gas and oil experiment technical field, and the key feature is the imported interface and the certain pressure nitrogen buffer tank of the pipe connection preliminary filling between the advection valve of backpressure valve, nitrogen buffer tank's a bottom connection pressure governor pump gear, the cone needle of needle sealing washer is connected to ejector pin front end axial in the back pressure valve body, and the cone needle holds the needle groove phase that has the valve body of drain pipe to laminate with corresponding, the utility model discloses a stability is not enough when installing the certain pressure nitrogen buffer tank of preliminary filling additional solving the device operation of present back pressure system before the valve body, and prefabricated in cone needle that ejector pin front end axial adds case polysulfone resin sealing washer and the valve body have that to mate and be connecte