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Filling Principle and Classification of Filling Machine

Jul. 25, 2020

China Automatic Liquid Filling Machine

What is a filling machine?


Filling machines are mainly a small class of products in packaging machines. From the perspective of material packaging, they can be divided into custom automatic liquid filling machines, paste filling machines, powder filling machines, granule filling machines: In terms of the degree of automation of production, it is divided into the semi-automatic filling machine and fully automatic filling production line. Recently, with the QS certification of food, edible oil manufacturers have begun to pay attention to product quality and packaging, so oil filling machines have a prominent position in filling machines.


Filling principle


Due to differences in the physical and chemical properties of liquid materials, there are different filling requirements when filling. The liquid material is filled into the packaging container by the liquid storage device (usually called the liquid storage tank), and the following methods are often used.


1) Normal pressure filling


Atmospheric pressure filling is to directly rely on the weight of the filled liquid to flow into the packaging container under atmospheric pressure. The machine that fills the liquid product into the packaging container under normal pressure is called the normal pressure filling machine.

The process of atmospheric filling is as follows: ①Inlet and exhaust, that is, the liquid enters the container and the air in the container is discharged:

②Stop the liquid inlet, that is, when the liquid material in the container reaches the quantitative requirement, the liquid inlet will automatically stop; ③Exclude the remaining liquid, that is, remove the remaining liquid in the exhaust pipe. This process is for those exhausted to the upper air chamber of the liquid storage tank. The structure is required. The atmospheric pressure method is mainly used for filling low-viscosity and non-gas liquid materials, such as milk, white wine, soy sauce, syrup, etc.


2) Isobaric filling


The isobaric filling uses compressed air in the upper air chamber of the liquid storage tank to inflate the packaging container so that the pressures of the two are nearly equal, and then the filled material flows into the container by its own weight. The machine that uses the equal pressure method for filling is called an equal pressure filling machine.

The process of isobaric filling is as follows: ①Inflate and equal pressure; ②Inlet and return gas; ③Stop the inflow; ④Release the pressure, that is, release the compressed gas remaining in the bottleneck to the atmosphere, so as to prevent the sudden pressure drop in the bottle from causing a lot of cold Bubbles, affecting packaging quality and quantitative accuracy.

The equal pressure method is suitable for filling gas-containing beverages, such as beer, soda, etc., in order to reduce the loss of gas (CO2) contained therein.


3) Vacuum filling


Vacuum filling is performed under the condition of lower than atmospheric pressure. It has two basic methods: one is the differential pressure vacuum type, which keeps the inside of the liquid storage tank in a normal pressure state and only pumps air inside the packaging container to form a certain vacuum degree, and the liquid material depends on the two containers. The pressure difference between the two flows into the packaging container and completes the filling; the other is the gravity vacuum type so that the liquid storage tank and the packaging container are in a nearly equal vacuum state. The liquid material flows into the container by its own weight. The machine that uses the vacuum method for filling is called a negative pressure filling machine. At present, the differential pressure vacuum type is commonly used in China, which has a simple structure and reliable operation.

The process of vacuum filling is as follows: ①The bottle is emptied; ②Inlet and exhaust; ③Stop the inflow; ④Reflow of residual liquid, that is, the residual liquid in the exhaust pipe flows back to the storage tank through the vacuum chamber.

The vacuum method is suitable for filling liquid materials with higher viscosity (such as oils, syrups, etc.), liquid materials containing vitamins (such as vegetable juice, fruit juice, etc.) and toxic liquid materials (such as pesticides, etc.). This method can not only increase the filling speed, but also reduce the contact and effect of the liquid material with the remaining air in the container, so it is beneficial to prolong the shelf life of some products. In addition, it can also limit the escape of toxic gases and liquids, thereby improving operation Conditions, but it is not suitable for filling wines with aromatic gas, because it will increase the loss of wine aroma.


4) Pressure method filling


Pressure filling is to control the reciprocating movement of the piston with the help of mechanical or pneumatic hydraulic devices and suck the liquid material with higher viscosity from the storage cylinder into the piston cylinder, and then force it into the container to be filled. This method is sometimes used for filling soft drinks such as soda. Since it does not contain colloidal substances, the foam is easy to disappear, so it can be directly poured into the bottle without pre-inflation by relying on its own strength, thus greatly improving the Filling speed.


5) Siphon filling


The siphon filling method is to use the siphon principle to make the liquid material be sucked into the container from the liquid storage tank through the siphon until the liquid level of the two is equal. This method is suitable for filling low-viscosity and gas-free liquid materials, with simple structure but low filling speed.


Filling machine classification


According to the transport form of the packaging container, it can be divided into the following types.


1) Linear filling machine


When filling, the packaging container moves linearly and intermittently from one station to another station, and the machine that completes the filling when stopped is called a linear filling machine.


2) Rotary filling machine


This type of filling machine, after the packaging container enters the filling station, rotates around the worktable for one week, and performs a constant speed rotation to complete the filling. .

Another type of filling machine is an aseptic filling machine, a Tetra Pak filling equipment commonly used for filling juice and milk, and filling equipment for flexible packaging of composite paper. The filling capacity is 0.25L ~ 2L, with brick-shaped, House shape, and triangle.

In daily life, liquids in commercial packaging involve many fields and a wide range. There are a variety of packaging containers, with packaging capacities ranging from tens of milliliters to hundreds of liters. Liquid filling machinery is mainly designed for three types of packaging containers: glass bottles, cans, and PET bottles.

In addition to the types of filling machines listed above, the manufacturer can also produce filling machines designed according to the special needs of customers, special packaging containers, and special products (such as high viscosity products). In many cases, there are several types of filling machines for the packaging of a liquid.

The use of mechanized filling methods and filling equipment can not only increase labor productivity, reduce product losses, and ensure packaging quality, but also reduce the mutual pollution of the production environment and the liquid being filled.


Industry Outlook


Filling machines are widely used in the food industry, beverage industry, daily chemical industry, etc. The competition of food packaging machinery is becoming increasingly fierce. The future food filling machinery will cooperate with industrial automation to promote the improvement of the overall level of packaging equipment and develop multi-functional, high-efficiency, low-consumption food packaging equipment.

The filling machine has always been a solid backing for the beverage market. Especially in the modern market, people’s requirements for product quality are increasing, market demand continues to expand, and enterprises require efficient and automated production. Under such circumstances, filling machines are even more important. Become hot filling equipment. In addition to the improvement of science and technology in recent years, China's Automatic liquid filling machine has also been developed rapidly, and the technical level, equipment performance, quality, and other aspects have been greatly improved. , Has played an important role in supporting the efficient and safe production of enterprises.