Piston Fillers for Thicker Products

As always, the annual PACK EXPO show at the beginning of this month brought out packagers from a number of different industries. However, LPS representatives seemed to talk to an abundance of people that were looking to fill bottles, jars and other containers with different types of sauces this year. While sauces come in many different varieties, there are two characteristics that are seen more often in sauces than in other products. First, sauces tend to be a little higher in viscosity than an average liquid product. Second, many sauces will contain particulates, from small spices to bigger chunks of vegetables, that can make filling a bit more of a challenge. However, a piston filling machine is well suited to meet these challenges.

Piston filling machines use a cylinder and a piston to create a highly accurate volumetric fill which is ideal for thicker products. As the piston retracts, sauces or other products fill the cylinder before being pushed in to waiting containers when by the same piston. Different fill levels can be achieved by lengthening or shortening the stroke of the piston (or by changing out the piston) and because the volume of the cylinder never changes, the volume of product being pushed into waiting containers will be consistent from cycle to cycle.

In addition, the wide open space of the cylinder allows particulates like those mentioned above, even the larger chunks found in some sauces, to pass through the product pathway, where some tubing and nozzles found on other types of filling machines may get clogged or jammed by particulates. Of course, many piston fillers still use a nozzle to release product in to the container, so that sauces with large particulates would require a nozzle that would also allow particulates to pass through as well.

Piston filling machines can be manufactured as tabletop, semi-automatic or fully automatic liquid fillers, and each is capable of handling thick products as well as particulates. The difference between the semi-automatic and automatic models generally comes down to operator interaction with the machine. Semi-automatic models typically require an operator to place and remove containers under the fill area while also activating the fill cycle by foot or finger switch. Automatic models work with a power conveyor and indexing system to remove the operator from the equation. Piston fillers can be manufactured with more than one fill head, and the actual design of the machine will depend on the product, containers, production rates and any other special considerations of any given project.

Piston fillers are often used not just on sauces and products with particulates, but also on other high viscosity products like pastes and gels that do not flow freely from a holding tank, vat or other product supply. Of course, other filling principles can be used for products both thick and thin as well. To learn more about the piston filling machine, or any of the filling solutions from LPS, and how they can help your own filling project, contact an LPS Packaging Specialist today.