Difference of back sealing and 3 side sealing
For our screw counting packing machine, the back sealing will suit for this kind of material well.
Plastic bags come in many different styles, but they can also be understood to be simple. The three-side bag is to seal the three sides of the bag, and to load things from the top seal, while the middle bag is from the middle to the plastic package. Packaged. Let's take a closer look at the difference between the back seal and the three-side seal.
1. Back sealing
The middle sealing bag is also called the back sealing bag. Its application range is very wide. Generally, candy, bagged instant noodles and bagged dairy products are used in this type of packaging.
The middle sealing bag can be used as a food bag to store food, medicine, cosmetics, frozen food, philatelic products, etc. It is moisture-proof, waterproof, and insect-proof. It can be reused, and it will be tightly sealed, non-toxic and tasteless with a single press. It has good flexibility and is easy to seal， suit for hardware, fastener packing very well.
2, three side sealing bag
The three-side sealing bag has the best air tightness, and the vacuum bag generally uses this bag making method.
Three-side sealing bags require vacuum packaging in many cases. This reason is also very diversified. Sometimes it may be to prevent food from spoiling, and sometimes to make the shelf life longer. Vacuum packaging is also commonly referred to as decompression packaging. The main purpose is to extract all the air in the packaging bag and then seal it so that the bag is always under high decompression.
For packing some of the small plastic items, special requirement from customer, they need 2 side sealing.
Anyway, for back sealing, the output will be more, and high effective, and 2 side sealing the speed will be low.
The production of the sealed bag and the three-sided sealed bag are produced by different equipments. Because of the different production steps between the two, there will be some differences in the use.
Careful customers must choose their own bag style.
Customize vertical packaging machine for hardware, fastener, plastic fittings etc......