The vacuum packaging machine can automatically extract the air in the packaging bag and complete the sealing process after reaching a predetermined vacuum. It can also be filled with nitrogen or other mixed gas, and then the sealing process is completed. Vacuum packaging machines are often used in the food industry because after vacuum packaging, foods are resistant to oxidation for long-term storage.
Vacuum, the term is translated from the Latin vacuo, its meaning is nothing. In fact, vacuum should be understood as a space where gas is thin. In a given space, the state of the gas below one atmospheric pressure is collectively referred to as vacuum. The degree of gas thinness in a vacuum state is called a degree of vacuum, and is usually expressed by a pressure value. Therefore, the vacuum packaging is not actually completely vacuum, and the vacuum in the food container packaged by the vacuum packaging technique is usually 600-1333 Pa. Therefore, the vacuum packaging is also referred to as a vacuum packaging or an exhaust packaging.
It was the first development period from the 1950s to the mid-1980s, which began with the manufacture of simple air extractors. At that time, there were less than 20 enterprises producing vacuum equipment in the country, and the products were mainly obtained in medium and low-grade vacuum, such as the mirror coating machine cigarette packaging machine. From the late 1980s to the 1990s, it was the second period of China's vacuum industry development. During this period, the number of production enterprises increased to nearly 3,000, and the number of employees reached 35,000. After the technical transformation of the “seventh five-year” and “eight-five” technology, the overall level of the vacuum industry has been greatly improved. From the processing conditions, advanced production equipment such as CNC machine tools and resin sand castings of machining centers began to be equipped with enterprises. By 1996, due to the pull of the magnesium smelting industry, the vacuum industry has developed rapidly.