Whether you work with the food, chemical, or pharmaceutical packaging industry, you must understand the liquid viscosity.
Knowing your product’s viscosity level will allow you to buy an ideal filling machine. Also, it will help you fill out the content more properly and quickly without spills.
In this article, I will discuss liquid viscosity in detail to give an overall idea. So, let’s dive in;
What Is The Viscosity?
Viscosity means the thickness and resistance level of a liquid item to flow. Liquid content like milk and honey has different viscosity rates for their rasistancy. For instance, water, juice, and other thin surfaces are low-viscosity products. When you fill these liquids into pouches, glass, or bottles, you will see they will flow smoothly and quickly.
On the other hand, different types of oil and liquid soap are thicker and have medium viscosity. They flow slowly, and filling them in any jar requires some time. However, honey, jam, and some butter are high-viscosity liquids; they are tough to fill. You have to use a spoon to do the filling process or consume.
How Do You Measure Viscosity?
Below, I have mentioned a few methods to measure viscosity by using different instruments.
Zahn Cup
This is a small cup with a long handle that attaches from both sides. It also has a hole at the bottom center, which changes based on the fluid type. To measure viscosity with it, take the cup and drip it properly into the surface. When lifting the Zahn cup, you should start recording the time.
Therefore, the product has low viscosity if the cup is empty in less time. On the other hand, when the liquid takes a long time to fall, it indicates high viscosity. This method is usually used in paint color.
Capillary Viscometer
The capillary viscometer is the earliest method in the history of liquid viscosity measurement. For this method, you need a capillary tube and record the time needed for the surface to pass the tube. So first, put maple syrup or water inside the tube. Then, you will see that maple syrup will take a longer time to flow through the tube.
In contrast, water viscosity is low, and will take a short time to do this. This way, you will measure that syrup is thicker than water, which means syrup has high viscosity.
Vibrational Viscometer
With a vibrational viscometer device, you can measure the viscosity accurately. Usually, this instrument uses a tuning fork or vibrating rod placed in the fluid. Therefore, when the sensor starts to vibrate, the liquid viscosity resists the motion. It changes the vibration frequency and measures the surface’s thickness level.
For example, high-viscosity or thick fluids slow vibration, whereas low-viscosity or thin fluids let vibration happen freely. This method can be used for precise industrial, pharmaceutical, and chemical measurements.
Falling Sphere
To operate this method, a sphere is dropped into the surface in a vertical tube. The time it takes for the sphere to fall a specified distance is recorded.
Then you can measure the viscosity based on the sphere’s drag force as it moves through the fluid. It is very popular among scientists and engineers.
Rotational Viscometer
This is an instrument used to measure a liquid’s viscosity. It does this by rotating a spindle or cylinder on the surface and measuring the resistance to the rotation. The higher the resistance level, the higher the viscosity. Typically, this instrument tests fluids like paints, oils, and polymers.
How Do Viscous Liquid Filling Machines Work?
No matter what kind of equipment, the usual viscous fluid filling method is similar. For this, set a box or holder in the right spot and line it up with the machine. Next, the surface is added to the container using a tube, nozzle, or other tools. A computer usually controls the process to ensure each container gets the right amount of liquid.
Different Types Of Viscous Liquid Filling Machines?
Several kinds of viscous filling equipment are available in the market. Each has unique benefits, some of which are-
Piston Filling Machine
This automatic machine can fill sticky, high-viscosity fluids. It is mainly run by a power source, which transfers the liquid to the pouches, cans, and other containers. The best part of this machine is that it can work without spills and minimize labor costs.
Some of the common types of materials you fill with the piston-filling machine.
- Soy sauces
- Food
- Jams
- Condiments
- Preserves
- Personal care products
- Cosmetics
- Pharmaceuticals
- Healthcare products
- Nutraceuticals
- Industrial and chemical products
Gravity Filling Machine
Choose a gravity-filling machine if you need equipment to fill thin or low-viscosity fluid. This machine uses gravity to let the liquid flow into bottles, pouches, and other containers. Therefore, all you have to do is fill the hopper with the surface and set a jar, bowl, pouch, or any other thing you want to fill under the machine. With the device’s nozzle, you can control the flow and shut off the machine when needed.
Let’s see the fluid you can fill with a gravity machine-
- Water
- Juice
- Milk
- Beverages
- Edible oils
- Some personal care products
- Cleaning products
Pump Filling Machine
This equipment is popular among customers as it is designed to deliver precise volumes of viscous liquid into containers. It runs by using a pump to transfer material from a bulk source to the packaging line. However, this liquid machine can be fully and semi-automatic.
Typically, the pump filling machine is ideal for sticky and high-viscosity contents-
- Creams
- Lotions
- Shampoos
- Syrups
- Conditioners
- Sauces
- Cleansers
- Liquid detergents
- Automotive and industrial liquids
Vacuum Filler
This machine is designed to fill viscous liquids into bottles or pouches with high precision. It operates by creating a vacuum in the filling chamber, which helps draw the liquid into the container. Then, through the tube or nozzle, this machine fills liquid into the bottles or pouches and seals them.
This is particularly effective for handling thick or foamy liquids, as it minimizes air bubbles and ensures smooth filling.
- Food
- Pharmaceuticals
- Chemicals
- Cosmetics
- Solvents
- Laboratory use
Overflow Filler
An overflow filler is designed for liquids with consistent viscosity. It uses a controlled overflow system to ensure each container is filled to the same level, regardless of variations in container size or shape. This method ensures uniform filling without spillage.
Some of the products you fill with this machine are-
- Food sauces
- Beverages
- Pharmaceuticals
- Condiments
- Healthcare products
- Personal care and household products
- Chemicals and industrial liquids
A Chart With Different Types Of Liquid Filling Machines
| Features | Piston | Gravity | Pump | Vacuum | Overflow |
| Viscosity Range | Low and High | Medium | Low to High | Low and High | Medium |
| Versatility | High | Medium | High | High | High |
| Speed | Moderate | Moderate | High | Moderate | Moderate |
| Accuracy | Excellent | Good | Good | Good | Excellent |
| Container Type | Various | Various | Various | Various | Consistent Fill |
| Foaming Control | Limited | Limited | Limited | Excellent | Excellent |
| Air Removal Capability | Limited | Limited | Limited | Excellent | No Air Removal |
| Hazardous Liquids | Yes | Yes | Yes | Yes | Yes |
| Maintenance Requirements | Moderate | Low | Moderate | Moderate | Low |
Benefits Of Viscous Liquid Filling Machines
Liquid viscous machines have several pros compared to other types. Below are a few benefits:-
- Higher speed: Viscous liquid filling machines can fill more bottles or pouches together than manual production. For instance, a 16-head device can fill around 120 containers in a minute. So, it will fill a wide range of cans daily and increase your production capacity.
- Reduced labor costs: As these machines work automatically, you don’t need to hire more workers. However, you can employ one to control the machine. This will reduce labor costs.
- Improved product quality: Quality is the main part of the liquid industry, and these machines are best for this. They can fill the bottles and pouches with precise and proper amounts and increase product quality.
- Simple operating system: Modern viscous liquid filling machines often feature user-friendly interfaces. Anyone can learn the operating system in a certain amount of time. Often, some machines need help to change over the bottle or pouch only.
- Versatile filling: No matter the product type, thick or thin, they can fill them efficiently. Also, they can fill the liquid in different measurement levels.
Things To Consider While Choosing Viscous Liquid Filling Machines
Now, let’s see which factors you should take into account while purchasing a liquid viscous machine–
Filling Speed
Depending on your production capacity, you should choose a machine. If you have a big company, choose a machine with a high speed, like it can fill around 100 containers in a minute. On the other hand, buy a machine that can fill 20 to 60 cans per minute for your medium or small productions.
Viscosity Of The Liquid
The viscosity level of the fluid will help you select a filling instrument. Therefore, if you work with high-viscosity or thicker fluid, choose a machine that can handle this, like a piston. On the other hand, for lower viscosity, go with gravity-filling equipment.
Accuracy Of The Filling Process
If you want machines to ensure precise filling, consider buying one with high accuracy. It ensures the correct and consistent filling, which is crucial for meeting regulatory standards.
Containers Sizes
Viscous liquid machines must match different sizes, typically ranging from 30 ml to 5 liters. So, before purchasing one, check that the equipment can handle your specific container dimensions.
Maintenance Requirements
Viscous machines often require high maintenance because they run smoothly for years. Maintenance includes daily cleaning, checking the lubrication system, replacing parts, and more. So, try to choose a machine that requires low maintenance to reduce your stress and cost.
Conclusion
To learn the viscosity level of any liquid is a must for you to run a business. However, you can measure the viscosity of liquids by using a different technique or machine. The right viscosity will help you to fill the product in jars, bottles, pouches, or any other packaging option.
FAQs
What is the liquid viscosity level?
The viscosity level refers to its resistance to liquid flow. Some fluids, like jam, are thicker and flow slower, which is called high viscosity. In contrast, water is thinner, and flow quickly means a low viscosity level.
Which viscosity is good?
The ideal viscosity depends on the product and packaging method. Low to medium-viscosity liquids are generally easier to handle, reducing the risk of clogging and ensuring smooth filling. However, high-viscosity products require specialized equipment for accurate and efficient packaging.
What is Centipoise?
Centipoise (CPS) is a unit of dynamic viscosity in the centimeter-gram-second (CGS) system. It measures a fluid’s internal resistance to flow. One centipoise equals one-hundredth of a poise. For instance, water at 20°C has a viscosity of about 1 CPS.
What temperature affects Viscosity?
Temperature significantly affects viscosity. When temperature increases, viscosity generally decreases. This is because heat reduces the internal friction between molecules, allowing the surface to flow more easily. Conversely, lowering the temperature increases viscosity. As a result, fluids become thicker and more resistant to flow.
