We encounter various types of liquids every day, from mineral water, yogurt drink, soda, and fruit juice that we drink to detergents, foaming agents, or thick liquids like honey, tomato paste, and sauce! Have you ever wondered how all these liquids are packaged? Certainly, one type of machine cannot be used to package all of them.
If we want to classify liquids based on their viscosity (thickness), one group would consist of high-viscosity (thick) liquids, while the other would consist of low-viscosity (thin) liquids. Specific machines are used to package each of these products, and they have different mechanisms. Stay with us as we explore the filling mechanisms in liquid filling machines for thin liquids and their features.
What are the types of filling machines?
To increase speed, precision, and efficiency, as well as ensure complete hygiene and safety, liquid filling machines are used in all industries. Before examining the types of filling mechanisms in thin liquid fillers, it’s useful to get familiar with other filling machines as well:
- Pressure filling machine: These machines perform the filling process with high pressure, which speeds up the process. Typically, they have a tank and pump at the back, and when a bottle is placed in the machine, the pump directs the material from the tank into the bottle under high pressure.
- Piston filling machine: This type of filling machine responds to the materials being filled and opens and closes based on the input material. The piston filling machine has a tank and performs the filling process with high precision and speed. It is mainly used for high-viscosity materials such as tomato paste, sauces, honey, etc., and has very little error.
- Powder filling machine: This machine is suitable for filling various powdered materials ranging from 2 grams to 2 kilograms. These machines come with different weight ranges, and the appropriate machine must be selected based on the product. The powder filling machine can be used for packaging various powdered products in the food, industrial, chemical, and hygiene sectors.
- Liquid filling machines: These machines are available in a wide variety and are offered with different mechanisms. To speed up the liquid transfer process, these machines typically use a pressure mechanism. Liquid filling machines can be categorized into the following two groups:
- Thick liquid filling machine: The thick liquid filler is used for liquids with high viscosity (resistant to flow), such as various chemical oils, grease, pharmaceutical products like syrups, honey, date syrup, and jams.
- Thin liquid filling machine: Thin liquids are those with low viscosity and do not resist flowing much. Liquids like water, doogh (yogurt drink), various herbal distillates, edible oils, medicinal syrups, perfumes, and others fall into this category. The filling mechanism in thin liquid fillers varies in different machines, and we will discuss it further below.
Features of liquid filling machines for thin liquids
Liquid filling machines for thin liquids are produced in various types, which can generally be divided into two categories: automatic and semi-automatic. These machines are equipped with a control panel, which is especially useful in automatic models. Through this panel, the operational capacity of the machine, such as the movement of containers on the conveyor, the opening and closing of nozzles for filling, and so on, can be adjusted and programmed.
In automatic liquid filling machines, the movement of containers is completely automated. Semi-automatic liquid filling machines have different features and functions; however, they still perform many tasks automatically. To use these machines, workers need to place the bottles or containers in the designated area, but the filling process and other tasks are carried out by the machine itself.
Thin liquid filling machines are also available in automatic and semi-automatic types. Since thin liquids are highly fluid and have low viscosity, a specific mechanism is required for packaging and transferring them into containers, which is different from the mechanisms used for filling thicker liquids. In the following, we will learn more about the mechanisms of thin liquid fillers.
Types of Thin Liquid Filling Mechanisms
Now that we are familiar with the types of filling machines and the features of thin liquid filling machines, it’s time to explore the filling mechanisms in thin liquid filling machines. In general, the filling systems in thin liquid filling machines can be divided into three groups: piston-cylinder, pump, and gravity, which we will review below.
Piston cylinder filler
The mechanism of this device is designed in such a way that it can be used for filling all types of liquids, whether thick or thin. Depending on the number of nozzles on the device, cylinders with completely equal volumes are manufactured and installed. These cylinders are equipped with two-way valves, one side of which is connected to the filling machine’s feed tank, while the other side is linked to the nozzles. When the piston moves backward, a vacuum is created inside the cylinder, the valve connected to the feed tank opens, and the suction pressure causes the material to move into the cylinder.
Due to the equal volume of the cylinders, the volume of liquid entering them is also completely uniform. In the next step of the process, the piston moves forward, closing the feed tank inlet and opening the nozzle outlet. As a result, the device directs the material inside the cylinder into the nozzle and then into the designated containers.
Pump filler
The pump liquid filling machine generally operates based on time. Various capacities (ranging from 450 cc to 20 liters) can be filled into containers by setting the desired time for the machine. For example, a pump filler can inject 500 cc of your product into a bottle within 5 seconds. The longer the set time, the greater the filling capacity of the machine. Therefore, the pump filler is not only suitable for filling different products with a single machine but also for filling products into various containers with different capacities.
Gravity filler
This type of filling mechanism in gravity fillers is only suitable for low-viscosity liquids. The maximum viscosity of these liquids should be lower than that of olive oil. The gravity filler machine has a tank positioned at the top, which is connected to the nozzles. When the nozzles open, gravitational force causes the liquid to flow downward.
The designated containers are placed beneath the nozzles, and the volume of liquid dispensed into them is controlled by opening and closing the nozzles. To prevent errors, the liquid level in the feed tank must be consistently maintained to ensure the pressure behind the nozzles remains unchanged. The liquid level inside the tank is regulated by level control sensors. Additionally, to prevent foaming during filling, the nozzle fills the container from the bottom and moves upward at a steady speed.
Final Words
In this article, we examined the different filling mechanisms used in liquid filling machines for low-viscosity liquids. We now know that these machines can be designed and manufactured with one of three mechanisms: piston-cylinder filling, pump filling, or gravity filling. Among these, the piston-cylinder mechanism offers significantly higher precision and speed with minimal error probability. If you opt for the automatic version of this machine, you will ensure a high level of efficiency for your business and boost production.
Frequently Asked Questions
✅What are the applications of the pump liquid filling machine?
This machine, due to its high pressure and power, is most commonly used for injecting thick liquids such as oil, grease, etc., into containers, as well as filling foamy and sticky liquids.
✅How many nozzles does the piston-cylinder liquid filling machine have?
The piston-cylinder filling machine is designed and produced in single nozzle, double nozzle, four nozzle, six nozzle, and eight nozzle models, depending on the customer’s order.
✅Which machine is better for filling high-value liquids?
The piston-cylinder machine, due to its high precision, speed, and minimal error, is the best option for filling high-value liquids.