Overloading liquid discharging device of LNG loading skid

The utility model belongs to the technical field of tank car filling of liquefied natural gas (LNG), and discloses an over-loading liquid discharging device of an LNG loading skid, which comprises a return gas pipeline, a nitrogen pipeline, an LNG liquid phase pipeline and a liquid discharging pipeline, and further comprises a communication pipeline connected between the nitrogen pipeline and the return gas pipeline, nitrogen of the nitrogen source sequentially passes through the nitrogen pipeline, the communicating pipeline and the return gas pipeline to conduct nitrogen charging and pressurization on the interior of the tank car tank body so as to achieve overloading liquid discharging. Nitrogen can conveniently and rapidly enter the tank car tank body through the communicating pipeline and the return gas pipeline to achieve nitrogen charging and pressurization, the pipe diameter size of the communicating pipeline is increased, therefore, rapid pressurization of nitrogen is achieved, and the liquid discharg