Filling Thick Products Requires a Little Extra Push

Common sense tells us that the thicker, or more viscous, a liquid product, the less free flowing that product will be. Many low viscosity products, with a water-like consistency, can be filled using a gravity principle, which generally allows product to flow from a raised tank and into bottles through the opening of valves for a set amount of time. Thicker products, like pastes or honey for example, would not lead to an efficient fill process if such products were simply allowed to flow into containers. For this reason, pump and piston fillers are often the best choice for higher viscosity liquids.

The key to moving thicker products lies in using pumps to move the liquid through the product pathway. Pump fillers achieve this by matching the type of pump to the product and project at hand to achieve a more time efficient fill. Pump filling machines can be manufactured as simple, semi-automatic tabletop filling equipment or as automatic machines to add to a completely automated packaging system. While pump fillers may use a time-based fill, they can also use a pulse based fill, which will use components of the pump to accurately fill containers by volume. For example, each pulse of a gear pump may be equal to a quarter or half turn of the gear. A specific number of turns of the gear will achieve the volumetric fill desired in each bottle.

While piston filling machines are placed in their own category of filling machines, they work like a pump filling machine in that a component of the filler helps move product through the pathway. The cylinder of the piston filler will be filled with product as the piston retracts. Once filled with product, the piston will re-enter the cylinder and push product into the waiting container or containers. As the volume of the cylinder never changes, the piston filling machine also offers an accurate volumetric fill for viscous products. Depending on the type of pump, both piston and pump fillers can also work for products that have larger particulates, such as dressings, sauces and similar products.

The speed of the fill is a necessary consideration when choosing the best liquid filler for any project. When products are high in viscosity, pump and piston fillers add that little extra push to keep fill times lower and help get product to the shelf. Visit the LPS filling machinery page on the website to learn more about either pump fillers or piston filling machines.