Machinery Spotlight: Liquid Fill Machines

A liquid filling machine is essential if you’re looking to transfer fluid into a container like a bottle.

It enables you to significantly speed up the production process. Adding to this, it provides accurate measurements so each container receives precisely the same quantity of your product.

Liquid filling machines are not all made equal. In fact, they come in a variety of sizes and types suited to different applications. 

Whether you need tabletop manually operated or fully automated filling and capping equipment, below you’ll find all the information you need to help you make the right selection.


What is a Liquid Filling Machine?

A liquid filling machine is used to inject fluid into bottles and similar containers. They are most commonly used in the food and pharmaceutical industry. In simple terms, it takes a large quantity of fluid and separates it into smaller containers ready for shipping.

You can use them for liquids such as water, milk, juice, carbonated drinks, alcohol, and medicines. In addition to these consumable products, they are useful for chemicals, lubricants, e-liquids, syrups, and much more.


How Does a Liquid Filling Machine Work?

The basic working is quite simple. You fill a tank or hooper with your chosen liquid. Then the fluid is drawn from the tank into tubes to a filling nozzle. A bottle or container is held under the nozzle and injects an accurate amount of liquid.

Smaller manually operated machines can be operated by an individual using a button or foot pedal. You can think of it a little like filling a vehicle with fuel. 

Larger automated assembly lines provide a more end-to-end solution with added functionality. This includes bottle sorting, conveyors, multiple nozzles, and enhanced accuracy. They can even cap and finish a container.

What are the Different Types of Liquid Filling Machines?

Now you understand the overall operation, let’s take a look at the different methods used to initiate liquid flows.

Pressure Filling Machine

Pistons and pumps give you high control of the speed and force at which filling occurs. Generally, they work across most viscosity of liquids including water, milk, and carbonated drinks. The pressure is beneficial when working with thicker substances such as syrup, liquid cheese, condiments, glues, and pharmaceuticals. 

Vacuum Filling Machine

These machines use a vacuum pump to initiate a flow and draw liquids from a tank or hopper to the filling nozzle. They operate at slow to medium filling speed. Most often, they are used for fluids like wine, spirits, perfumes, and chemicals.

Gravity Filling Machine

This uses the weight of the liquid to fill containers via a nozzle. The fluid is stored in an elevated tank or added to a funnel above your container. When the nozzles are opened, it relies on gravity to enable the flow down into your bottles. It works with a wide range of liquids at slow speed and is particularly good for froth and foam, although the thickest substances won’t fill efficiently with this method. 


Weight vs Volumetric vs Level Filling Machine

The type of machine also refers to how the liquid is accurately measured. There are three different methods to consider all of which suit particular substances. These are Weight, Volumetric, and Level filling.


This enables you to set the machine to issue a chosen volume via a flow metre to match the container size. You can fill a container with the exact same amount of liquid no matter how it looks visually or even the size of the container. If this accuracy is important, for products like medicine, then the volume is a consistent measurement.

Handily, the capacity of a liquid container is measured by volume. Remember, a liquid takes on the shape of its container. This is useful as it tells you the amount of fluid your container holds rather than the interior measurements or space it displaces. Volumetric capacities include litres, pints, gallons, and fluid ounces.


A level filling machine does not take the exact volume into account. It simply fills a container up to a specified level. This delivers a more visually appealing product but inconsistencies in the exact amount of liquid. Most bottles have minor variations to their final volume after manufacturing even if they appear visually identical. So every container will look identical but there will be a tiny difference in the amount of product.


This allows a machine to fill based on a set weight and can be used with liquids, powders, solids, and gas. The final container is placed on a weighing scale to control the filling process. Once the target weight is hit, the nozzle automatically closes. This method can be used with a wide range of substances, often in combination with pouches, sachets, and bags, along with bottles. It is popular with pharmaceuticals, condiments, and similar thicker substances.


How do I Choose a Liquid Filling Machine?

With all these considerations, you might be wondering how you choose the best liquid filling machine. Well, here’s what you should take into account.

  1. Cost 

If you’ve been researching elsewhere on the internet you will notice that price and budget are often ignored. Of course, this is the most important factor as your budget determines the level of equipment you are looking at.  

You need to weigh up the value of your investment, especially if you’re borrowing to finance the purchase. Take the time to assess the current and future demands of your filling machine to understand the cost-effectiveness compared to your budget.

With a lower budget of under £10,000, you’ll be looking at countertop manual fillers with pressure and pump capabilities. This makes a great starting point allowing for versatility in use, plus you can add automation capabilities as your budget grows. Although you’ll be restricted in quantity and demand you can fulfil.

For larger operations consider automatic fillers and production lines which reduce labour while increasing output speed. Time is money, right? So the ability to sort bottles, and accurately fill from multiple nozzles, and cap enables mass production. You can even discuss bespoke designs with equipment manufacturers. 

  1. Liquid Viscosity

Viscosity is the measure of how thick or the resistance of a fluid. For example, water is a low viscosity liquid while syrup is high viscosity. 

This determines the type of machine you require. A gravity filler can be good for low viscosity or delicate liquids like water or foam. On the other hand, thicker substances need more force so a pressure filling is more suitable. 

You can think of it like pouring water out of a bottle compared to ketchup. Water free flows using gravity, whereas ketchup is thicker requiring a squeeze of pressure to start the flow.

  1. Container Type

There are millions of different container types. If you have already selected your bottle or container, it is critical to ensure the machine is compatible. Make a mistake here and you’ll have a frustrating experience when you try to start production. 

Discuss with the equipment manufacturer about the container shape and material it can accommodate. Ask about the compatibility with glass, metal, and plastic as they all have different properties related to sorting, filling, and capping. 


What is the Best Liquid Filling Machine?

If you've read this far then you’ll understand that there is no single best liquid filling machine. You need to select equipment that suits your individual requirements. 

You can use the information above to help guide your decision in understanding the options available and questions to ask.