This process is completed by the steam heat shrink machine: The water tank is connected to the finished water pipeline. A float-type electronic water level controller presets the water level. The electric heater heats the water in the kettle. When the preset value is reached (2 to 4 atmospheres) (this process takes about 10-20 minutes), the steam temperature is 140-170℃, and the machine can start working. When the barrel passes under the steam diffusion hood, the steam is sprayed downward to heat the neck of the barrel, completing the heat shrink film wrapping.