Filling Machines and Nozzle Selection

While many different nozzles will work on many different filling machines, choosing the correct nozzle for any given packaging project will help to add efficiency and consistency to the fill. Every filling process will have its own unique set of factors to consider, but listed below are some of the most common factors that will affect the nozzle choice.

Bottle Size

Packagers look to filling machinery to add speed to their packaging process and large bottles can take extra time to fill, and fill accurately, by hand. Filling nozzles are available in a variety of sizes, and the size of the nozzle should match the size of the bottle. For instance, using quarter-inch nozzle to fill a gallon bottle may not provide the most efficient fill. Using a larger nozzle allows big bottles to be filled expediently and helps packagers to meet production goals.

Speed is not the only consideration, however. On smaller bottles, a large nozzle may fill the container too quickly, leading to inaccurate fills or spills and splashes during the process. Matching the nozzle size to the bottle size can help resolve these and other filling issues.

Bottle Opening Size

Of course, the bottle opening will also play a part in selecting the correct nozzles, regardless of the bottle size. If the larger bottle in the example above were unique in having a smaller than normal opening for product, the nozzle size would need to be adjusted to ensure product is reaching the container without spills or splashes as well. The nozzles chosen for any project will obviously need to fit within the opening allowed by the container.


When filling by volume, level or any other method, product that foams can create havoc when the bubbles settle. Several methods, including the overflow method described below, can be used to control foam during a fill. These range from the unique nozzles found on the overflow filling machine to using a diving or bottom-up fill nozzle to reduce agitation. Choosing a nozzle that controls foam allows the packager to produce reliable and consistent fills based on whatever fill principle they choose.

Fill Principle

From gravity to pump and piston, nozzles can vary in size, shape and even material. But some filling machines are defined by the nozzles they use. The overflow filler is employed to fill bottles to the same level regardless of the interior volume of the bottle. Though in many cases volume will be the same or very similar, this filling machine places the level of the fill over the actual volume of product. In doing this, a specific nozzle is necessary. Nozzles for the overflow filler create a seal over the bottle opening and release product until it reaches the overflow port on the unique nozzle, at which point liquid normally returns to the holding tank, allowing each bottle to reach a specific level and no more.

While overflow nozzles come in different sizes and several different variations, the build of the nozzle will remain mostly the same to achieve the desired fill level. For this reason, the filling principle used for a packaging project can affect the type of nozzles used as well.


Product with particulates such as grit in soap or even chunks of fruits or vegetables in some food products must allow enough room for particulates to pass through and into the container. For this reason, narrow or small diameter nozzles often will not work. Particulates can block or clog the nozzles and have a negative effect on the consistency of the fill. Projects with particulates may need both a certain filling machine and unique nozzles to efficiently prepare products.


Product viscosity will almost always be taken into account when choosing the correct nozzles for a filling project. Depending on the principle used to fill, certain products may tend to drip or string after the fill is completed. Certain nozzles can work to control drips and strings and may even include the diving head or bottom-up fill nozzles mentioned above. Choosing the correct nozzle for the product viscosity ensures not only the right amount of product enters the container, but also that excess product does not drip onto the conveyor system or onto the outside of containers.

Proper nozzle selection can add efficiency and reliability while also ensuring clean container and finished products. While a wide variety of choices are available for most filling machines, Liquid Packaging Solutions can always help to identify the best choice for any packagers project.