Any packaging machinery manufacturer probably has a place on their website or in their brochure that discusses the correct filling machine for a given product. Many times these discussions will center around the viscosity of the product to be fill.d. In general, there are liquid fillers, like a gravity filler, that multihead weigher are better suited to thin, free-flowing products. On the other hand, some filling machines, such as pump fillers, will handle thick, more viscous products. Unfortunately, many packagers, packaging facilities and contract packagers work with more than one product, and those products will vary in viscosity. Given that purchasing several different types of filling machines can put a strain on the budget, what other options are available to these packagers?

The reality is that while some machines are better suited for thin or thick products, some machines can also handle low to high viscosities. Both pump filling machines and piston fillers may work with lower viscosity, free-flowing products as well. With this being the case, the next logical question is why even bother to manufacture or market overflow fillers and gravity fillers for thin products, if pump fillers and piston fillers can handle all products? The simple answer is that product viscosity, while a very important factor, is still only one factor to be considered when choosing a filling machine.

Each type of filling machine offers unique benefits or advantages that might not be seen in equipment using a different type of filling principle. For instance, an overflow filler allows bottles and containers to be filled to a consistent level, even where the interior volume of a container varies slightly. A piston filler, on the other hand, will fill with a consistent and accurate volume, even if the levels in the container may be slightly off. For products packaged in a clear container, the level fill offered by an overflow filler may be advantageous in creating an aesthetically pleasing shelf presence. Where a level fill is not important and an accurate volumetric fill is not a necessity, a gravity filler may be the most economical choice for a packager. So while piston fillers and pump fillers may be able to fill products both thick and thin, they will not be the ideal choice in every given situation.

But again, for companies packaging multiple products with varying viscosities, all factors may support the use of the pump or piston filler. Absent specific requirements regarding the filling principle (such as the level fill discussed above) the ability to run multiple products on a single machine may ease the burden on the operators of the packaging line. Economically, purchasing one packaging machine to handle all products is likely the best choice, depending on production demands and the amount of time that will be spent changing over from one product to another. Like all filling machines, pump and piston fillers are available as fully automatic packaging machines as well as tabletop and semi-automatic models. Automatic machinery will almost always be accompanied by an easy to use touchscreen interface that will allow for the recording and recalling of recipes. Each recipe will store the times, delays and durations necessary to run any one given product, easing the burden of initial set up. Tabletop and semi-automatic machinery will normally use a simple switch to activate the fill cycle, again easing the burden on the operator.