Classification and form of sealing machine
After the packaged product is filled into the packaging container or directly sent to the wrapping material sheet, it enters the indispensable container sealing process in the packaging process. Container sealing can effectively protect the product, so that the product is not damaged and deteriorated due to the impact of packaging operations during the shelf life, and is also conducive to the storage, transportation, sales and use of the product. The quality of packaging depends to a large extent on the quality of sealing, and the selection of suitable sealing machinery to achieve mechanization and automation of the sealing process is an important guarantee for improving the quality of sealing.
6.1.1 Classification of sealing machines
Sealing machinery is divided into three categories: sealing machine without sealing material, sealing machine with sealing material and sealing machine with auxiliary sealing material: sealing machine without sealing material includes hot pressing sealing machine, pulse, fusion welding, embossing, folding type, interpolation sealing machine; Sealing machines with sealing materials include hydraulic, crimped, pressure and screw-on sealing machines; Sealing machines with auxiliary sealing materials include ligation, tape, bonding and staple sealing machines.
6.1.2 Sealing form
According to the type of container and its sealing requirements for the product, the common sealing forms are as follows, as shown in Figure 6-1.
- 1. 2. 1 Crimped seal
As shown in Fig. 6 - 1 (a), the flanged tank body and the inner periphery of the lid coated with sealed filler are hooked, curled and pressed tightly to make the container sealed. This sealing form is mainly used for sealing metal containers such as tinplate cans and aluminum cans.
- 1.2.2 Gland sealing
As shown in Fig. 6 -1 (b), (c), the inside of the lid is coated with sealing packing, when the outer lid is pressed and bites the bottle body or tank, the sealing packing is deformed by pressure to play a sealing role, and because the corrugated periphery of the outer cover is stuck in the lower edge of the bottle a convex edge to maintain the seal. Fig. 6-1 (b) This sealed a form is mostly used for the lid of a wide-mouth container of bottled food (kimchi, jam, meat, etc.). Figure 6-1 (c) is a crown type cap, mainly used for bottled beer, beverages, alcohol, etc.
6.1.2. 3 Screw cap seal
Tighten the threaded cap on the container opening so that the gasket or the stopper inside the bottle mouth is elastically deformed to seal it, as shown in Figure 6-1 (d). This form of sealing is mainly used for plastic or metal parts with lids, while the tank is a container with a combination of glass, ceramic, plastic or metal parts, such as bottled milk powder, toothpaste tube, etc. Screw caps are easy to open and seal, and can be reused for a wide range of applications.
Canned food wide-mouth bottles, in order to facilitate consumers to open, mostly use multi-head oyster pattern, that is, in the bottle sealing part to make three or four courses of grasshopper segments, the length of each * grain is about the length of its full circle of oyster patterns 丨/3, and has a larger lead; The inside of the corresponding cap is made into several convex claws suitable for the number of lines of the bottle* in order to connect with the bottle.
- 1.2.4 Pressure plug seals
As shown in Fig. 6-1(e), the inner plug with a certain elasticity is pressed into the container mouth at mechanical pressure, and the squeeze deformation between the plug and the bottle mouth surface is made to seal it. This sealing form is mainly used for cork stoppers, rubber stoppers, plastic stoppers and glass bottles sealed containers, such as bottled wine, oil repair, vinegar and so on. In many cases, the combination of corks and stinged bottle caps is also used to achieve packaging sealing, such as bottle sealing of high-grade wines, pharmaceuticals and toxic substances. After the bottle mouth is pressed and sealed, it is supplemented by a wrong seal, a screw cap seal or a cap seal to improve the sealing of the seal.
6.1.2. 5 Rolling corrugated seals
Rolling corrugated sealing refers to the sealing method of placing a thin metal cap shell that is easy to form on the top of the neck, rolling the metal cup with a roller, and rolling out the oyster pattern exactly the same shape as the bottle mouth oyster, as shown in Figure 6-1(f). When this cover is opened, the metal cover will be disconnected along the preformed indentation around the skirt periphery, so this cover is also called a twisted cap. And because this sealing is convenient to identify whether it is unsealed or not, it is also called an anti-theft cover. It is often used for sealing glass bottles of high-grade wines such as wine and brandy.
- 1. 2. 6 Piping seals
The bottom edge of the cylindrical metal cover is deformed and pressed against the seal formed on the lower end face of the neck flange, as shown in Fig. 6-1(g). An elastic rubber pad located between the neck flange and the cap allows the seal to be reliably sealed. Wide n bottles for food cans are commonly used for this sealing.
- 1.2.7 Folding seal
The opening of the packaging container is flattened and folded several times to make it sealed. This sealing form is mainly used for semi-rigid containers, such as aluminum tubes filled with paste-like materials. Usually, indentations are often required after folding and sealing to enhance their sealing effect. Such as tooth sound, shoe polish tail and other packaging seals.
The choice of sealing form is not only related to the material of the packaging container, but also to the production process. General glass bottles are mainly selected with glands, screw caps, anti-theft caps, piping sealing, pressure plugs and other structural forms. Plastic bottles are often sealed with a screw cap, a pressure stopper and a cockroach screw cap. Metal cans are often sealed with a crimped edge. In order to reliably realize various forms of sealing operations, the corresponding sealing machinery should be appropriately selected according to specific conditions.
At present, all kinds of sealing machines in China are widely used. In addition to the sealing machine used alone, there are many sealing machines and other machines together with the production of automatic lines (such as capping machine in the filling production line and the filling machine to form a unit), which greatly improves the degree of production automation and efficiency, reduces the labor intensity of the work, and improves the packaging quality. Here are a few common sealers.