Packagers use liquid filling machines to dispense liquid-based products such as water, alcoholic beverages, carbonated drinks, pharmaceutical, and cosmetic products into various containers. No matter what liquid product you are packaging, the first question you should ask yourself is whether you want consistent volumes or fill levels across all of your containers.
Volumetric and liquid filling machines are the two most common liquid fillers in the market. Each filling principle provides different benefits for experienced packagers. But, for those who are new to the industry, the difference might not be that obvious. So, in today’s discussion, we will tackle the difference between the two. Read on if you want to know more!
A volumetric filling machine fills containers with a consistent volume of the product through a time-based filling principle. Regardless of the discrepancies in your containers’ interior volumes, volumetric fillers will make sure that each container is filled with the same amount of product. So, some containers may look less filled or more filled compared to the others.
• Gravity Fillers
These fillers hold the product in a tank located above the filling nozzles and use gravity to help in the filling process.
• Piston Fillers
Instead of pumps, piston fillers use pistons to push the product into the waiting containers.
• Pump Fillers
Pump fillers use different kinds of pumps to match your liquid product. They add a little push to get thicker liquids into your containers.
Most containers will have minor volume variations that are naturally occurring even if they appear to have the same shape and size at first glance. Liquid filling machines fill your containers up to a specific level, regardless of the differences between the volumes of the liquid in each container.
Also known as overflow filling machines or fill-to-level machines, liquid filling machines provide your containers a cosmetic fill in such a way that all container fills will look identical. Though this may differ from container to container.
Volumetric filling machines use a variety of nozzles for matching your liquid product and other requirements. But, generally speaking, all nozzles will work the same way – they will open for a specific amount of time which allows product flow from the holding tank to the waiting containers. The tank sits above the filling nozzles and valves.
Most volumetric fillers allow you to adjust the fill time of each individual nozzle, even to fractions of a second, to achieve greater accuracy. When the predetermined time is reached, the filling nozzles will stop the product flow. For semi-automatic machines, you need to activate each fill cycle using a finger or a foot switch, while automatic ones will come with touchscreen PLC control panels.
Liquid filling machines use a special nozzle that both seals over your containers’ opening and allows the liquid product to flow back to the tank. This can eliminate any product waste.
As the fill nozzles seal over the containers, the fill port opens to allow the product to flow to each container. Once the fill reaches a pre-set level in your containers, the product withdraws from them through the return port. Thus, “overflowing” from each container and back to the holding tank.
Liquid fillers in semi-automatic and automatic designs work the same way. The main difference is the activation of each fill cycle – semi-automatic machines use switches while automatic ones use PLCs.
Volumetric fillers are ideal for opaque containers since inconsistencies in the fill levels will not be noticeable. Inconsistent fill levels are not appealing on the shelves if you are using clear containers.
Gravity fillers are economical solutions for free-flowing liquids requiring volumetric fills. While pump and piston fillers are ideal for handling viscous liquids that need extra help before they can reach the containers. Examples of high-viscosity liquids are oils and gels.
You can also use piston filling machines for handling products containing large particulates like bits and pieces of fruits. But, do take note that you will need different types of pistons for filling different container sizes.
Although pump and piston fillers are good for viscous products, they are also suitable for low-viscosity liquids. Pump fillers come in a variety of pumps for handling different liquid viscosities.
There are times that inconsistent fill levels are an issue especially if you are handling clear containers in which the product will be visible to your consumers.
Liquid filling machines use the overflow filling principle which provides cosmetic fills. Thus, packagers using clear plastic bottles or glass prefer these machines. This is because the consistent fill levels give an aesthetically pleasing appearance to your containers once on the shelves.
Moreover, overflow filling machines are ideal for low-viscosity liquids and for products that foam which you need to control during the filling process.
Other liquid filling machines exist in the market but volumetric and overflow filling machines are the most popular ones. Your choice between these two depends on whether you would want the product volume in each of your containers to be identical or look identical to your customers.
By the way, if you are looking for can filling machine manufacturers in India for every application, you can find it here. And if you want to learn more about your filling machine options, feel free to contact our experienced engineers. We can customize your machines to suit your specific needs.