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The process flow of LNG vehicle refueling stations consists of four stages: unloading, pressure regulation, refueling, and pressure release. 1. Unloading process: There are three methods for transferring LNG from road tankers or containers into the LNG storage tanks at gas stations: booster unloading, cryopump unloading, and combined booster and cryopump unloading. 1) Unloading the booster: After unloading, it is necessary to reduce the pressure in the tank truck by 0.2–0.3 MPa; a large amount of gas must be expelled, which takes some time. 2) The gas space of the LNG truck is connected to that of the storage tank, and the gas is transferred to the tank via a cryopump. Disadvantages: High power consumption, complex manufacturing process. 3) Combined unloading using a booster and a cryopump: First, connect the gas space of the LNG truck to that of the storage tank, then disconnect them. During unloading, the booster is used to increase the pressure in the truck, while the cryopump is used to transfer the LNG into the storage tank. Disadvantages: It consumes electricity, produces exhaust gases, and has a complex manufacturing process. The second unloading method is more commonly used. 2. Pressure regulation process: The pressure inside the on-board gas cylinder is relatively high, typically ranging from 0.5 to 0.8 MPa. The lower the pressure during transportation and storage, the better. Therefore, before filling the vehicle with gas, it is necessary to increase the pressure in the storage tank. There are three methods for this: increasing pressure using a compressor, increasing pressure through low-speed pumping circulation, or combining both a compressor and low-speed pumping circulation to raise the pressure. 3. Gas filling process: After being pressurized by a cryopump, the gas is metered and then filled into the vehicle’s gas cylinders by a gas filler; this can be done either in a single-line or double-line setup. When the pressure in the on-vehicle gas cylinder is low, an upper spray method is used to reduce the pressure and minimize the emitted gases. When the pressure in the on-vehicle cylinder is high, dual-line filling is used, and the gas inside the cylinder is recovered into the storage tank. 4. Pressure relief process: Overpressure is released by the safety valve.