Generally, the canned food factory adopts this type of horizontal sterilization pot when the canned food is heated and sterilized at normal pressure by boiling. This equipment can achieve back pressure sterilization by introducing compressed air. If the cooling needs to be carried out in a pot, a water pump must be driven into the water spray pipe on the top of the pot (or a water circulation system is used).

During sterilization, the temperature inside the can will exceed the pressure outside the can (inside the pot) due to the temperature increase of the can. Therefore, in order to avoid pressurizing and jumping the lid in the glass jar during sterilization, the two ends of the tinplate can project convexly, and the back pressure must be applied, especially for meat cans that require higher sterilization temperature.

The use of back pressure sterilization is to use compressed air to increase the pressure in the pot to prevent canning and canning. The operation is described as follows: Since compressed air is a poor heat conductor, the steam itself has a certain pressure. Therefore, during the heating process during sterilization, compressed air is not put in, and only when the sterilization temperature is reached, the compressed air is opened into the pot, which increases the pressure in the pot by 0.5 to 0.8 atmospheres. After sterilization, when the temperature is cooled down, the supply of steam is stopped and the cooling water is pressed into the water spray pipe. As the temperature in the pot drops and the steam condenses, the pressure in the pot is reduced by the pressure of compressed air to compensate.

In the sterilization process, pay attention to the initial exhaust, and then vent steam to allow steam to circulate. It can also be deflated every 15-20 minutes to promote heat exchange. In short, the requirements for sterilization conditions must be met. The sterilization temperature, the sterilization pressure, the sterilization time, and the operation method are all specified by the canned product.