Precooling treatment method and device of LNG filling machine and LNG filling machine

The invention discloses a precooling treatment method and device of an LNG filling machine, and belongs to the technical field of computer application. The method comprises the steps that a starting instruction, aiming at precooling operation, on the LNG filling machine is responded to so as to generate a precooling command of the LNG filling machine; the medium parameters of a flowmeter are acquired when precooling operation is executed to the LNG filling machine to complete the set precooling period; when it is judged that media in the flowmeter do not reach the preset precooling conditionsaccording to the medium parameters, it is detected and judged that precooling operation is abnormal through the medium parameters, and an abnormal detection result is obtained; and according to the precooling information of the LNG filling machine, abnormal precooling records are generated and stored in the LNG filling machine. In addition, the invention provides an abnormal precooling record management method and device