Working principle: 1, direct heating, sterilization, cooling; 2, heating, hot water tank shift process set temperature; 3, the product into sterilization kettle, kettle door; 4 heart open balance device, the technology of the hot water tank water through the pump in the autoclave, arrival process set liquid level; 5, using circulating pump to circulation of sterilization process water in the kettle, steam by steam injection, mixer into circulation heating temperature to the process of sterilization temperature;6, entered the stage of sterilization, circulating pump has been in an open position, temperature fluctuations, by automatically steam valve switch control, to realize the stable temperature control; 7, after the sterilization phase, stop injecting steam inside the kettle; 8, the sterilization process water through the pump back to the heat water tank, arrange another time to store the sterilization, closing balance device; 9, through the cold water pump to infuse water kettle sterilization and cooling in the kettle products.