The Many Different Designs of Filling Machines

The term filling machine seems like a pretty simple and self-descriptive phrase, meaning a machine that fills something. In the case of NPACK, that something typically involves a liquid being filled in to a bottle or other container. However, the truth is it is very unlikely that any two filling machines are ever built the same (though there are some exceptions, for example when a packager uses multiple machines to meet production demand). The design of a liquid filler depends on so many different factors, there is simply no way to describe, or even imagine, every possible solution. Below we look at a few different designs and the reasons for using one over another.

To begin with, the principle used for any filling machine will most obviously have a direct bearing on the design of the machine. A gravity filler, for instance, will use a tank above the fill nozzles. This tank will allow product to flow through tubing and nozzles by the force of gravity for a volumetric fill. Free-flowing products work well with this machine, which lets an operator set a fill time for each individual head for accurate results. The overflow principle, on the other hand, uses a recirculation tank that allows product to overflow out of the bottle once a certain level is reached, moving back in to the ground level tank for use during a later fill cycle. Rather than volume, the overflow filler hits a consistent level on each bottle filled, even if slight differences in volume occur. A piston filler fills a cylinder with product, then using the piston to push product from the cylinder into waiting containers through one or more fill nozzles. While also using a volumetric fill, piston fillers work much better with higher viscosity products that do not flow freely and need a little extra help reaching the containers. These are only three of the filling principles that may be used for any project, but the designs of the machine change from a raised tank, to a ground level tank, to a hopper or no tank at all! Additional principles exist for other filling machines, all of which may vary in design, but the filling principle is not the only factor to affect which design in correct for a given project.

Levels of automation will help to determine whether semi-automatic or automatic filling machines are the correct solution for any filling project as well. Semi-automatic liquid fillers, while utilizing almost all of the filling principles as full-frame, automatic equipment, can be designed to take up no more space that a tabletop. In fact, tabletop filling machines are available in all of the principles mentioned above and more. In the alternative, fully automatic filling machines simply would not fit on any tabletop, or at least not in any useful manner! These filling machines are manufactured on a full, portable frame that allow them to roll up to a power conveyor system and quickly and continuously fill containers. The design of the tabletop machines also allow room for an operator to move bottles in and out with each cycle, whereas the fully automatic liquid fillers require no such interaction. In between the tabletop and the fully automatic machines, there lie literally hundreds, if not thousands, of design options, depending on the needs of the packager.

Finally, product, package and other components can also have an effect on the design of a filling machine. For example, very small packages, such as vials or tubes, may actually require or benefit from some type of monoblock filling line. The monoblock line would use a starwheel to help stabilize bottles as they were filled, with the starwheel simply being a notched wheel allowing containers to fit comfortably in to the notches. Rounded bottom tubes or vials simply would not work well running quickly down a conveyor system without some type of assistance (which is actually another option - using pucks to hold such containers.) The point, however, is that no one can truly imagine each and every possible design for a liquid filling machine! At NPACK, a big part of our job is to gather all of the information on a packaging process and help to identify the most economical, efficient and effective filling solution possible for each unique project. To learn more about any of the filling machines mentioned above, or any of the other packaging equipment manufactured by NPACK, feel free to contact a Packaging Specialist at the NPACK offices during business hours from 8 A.M. to 5 P.M. Monday through Friday.