After the product is placed in the packaging container, in order to keep the product sealed and preserved, to maintain product quality and to avoid product loss, the packaging container needs to be sealed. This operation is done on the sealing machine. A sealing machine is a machine that seals a container after it has been contained in a packaging container.
There are many materials for making packaging containers, such as emulsifying cans, plastics, glass, ceramics, metals, composites, etc., and the shape and physical properties of the packaging containers are also different. Therefore, the sealing form and sealing device used are not same. Generally according to the mechanical properties of the packaging material, it can be divided into the following two categories:
(1) Flexible container sealing device
The flexible container is a bag type container made of a flexible material such as paper, plastic film, composite film or the like. The sealing of such containers is mostly combined with bag making and filling, and is rarely used independently. The sealing device is different due to different materials.
1 paper bag sealing device. For paper materials, it is common to apply the adhesive at the seal and then apply mechanical pressure to seal.
2 plastic film bag and composite film bag sealing device. Many plastics have good heat-sealing properties. Plastic bags or composite bags made of such plastics are generally heated directly at the seal and subjected to mechanical pressure to fuse them.
(2) Rigid container sealing machine
Rigid container emulsifying tank equipment refers to the container whose shape is not easy to change after the container is formed. The sealing is often made of different types of covers. The commonly used sealing machines are as follows.
1 screw cap sealing machine. The cover is machined with internal threads in advance, and the threads are single or long. For example, the medicine bottle uses a single thread, and the can bottle uses a multi-head thread. The machine is rotated against the mouth of the container by rotating the cover.
2 roll sealer. The cover is mostly made of aluminum and has no thread beforehand. The aluminum cover is rolled by a roller so that the thread having the same shape as that of the bottle mouth is formed, and the container is sealed. Such a cover will be broken along the periphery of the skirt when unsealing, and cannot be restored, so it is also called "anti-theft cover". This machine is mostly used for the sealing of high-grade alcohol and beverages.
3 piping sealing machine. It firstly puts a cylindrical metal cover on the mouth of the bottle, and rolls the bottom edge with a roller to deform it inwardly, and seals the flange of the bottle to seal it. This machine is mostly used for sealing packaging of wide-mouth cans and the like.
4 gland sealing machine. It is a crown cap sealing machine specially designed for beverages such as beer and soda. The crown cap is placed on the bottle mouth, the gland mold of the machine is pressed down, and the corrugated periphery of the crown cap is squeezed and contracted, and is caught on the flange of the neck of the bottle mouth, thereby causing mechanical hooking between the cap and the bottle mouth. Thereby the bottle is sealed.
5 pressure plug sealing machine. The sealing material is a cork made of a material having elasticity such as rubber, plastic or cork, and its elastic deformation is used to seal the bottle mouth. When the machine is sealed, the stopper is placed above the bottle mouth, and the sealing is packaged by pressing the bottle stopper into the bottle mouth by the vertical pressure. The plug seal can be used as a separate seal or as a combination seal with the cap.
6 roll edge sealing machine. This machine is mainly used as a sealing for metal food cans. It uses a roller to seal the can lid and the periphery of the can body flange by crimping, hooking and pressing each other.
Sealing machine working principle and structure:
The general sealing machine is composed of a frame, a speed reduction transmission mechanism, a sealing printing mechanism, a conveying device and an electrical and electronic control system. When the power is turned on, each mechanism starts to work, and the heating element is heated after being energized, so that the upper and lower heating blocks are heated up sharply, and the temperature is controlled to the required temperature by the temperature control system, and the printing wheel rotates. The price of the emulsion tank starts to be cooled according to the needs of the cooling system. With the transfer, and adjusted by the speed control device to the required speed.
When the package containing the article is placed on the conveyor belt, the sealing portion of the bag is automatically fed between the two sealing tapes in operation and brought into the heating zone, and the heat of the heating block is transferred to the sealing portion of the bag through the sealing tape. The film is melted by heat, and then passed through the cooling zone to appropriately lower the surface temperature of the film, and then rolled by a knurling wheel (or a printing wheel) to bond the upper and lower plastic films of the sealing portion and press the mesh pattern (or printed logo) ), the sealed bag is sent out of the machine by the guiding rubber belt and the conveyor belt to complete the sealing operation.