Understanding Starwheel Use for Packaging Equipment

Understanding Starwheel Use for Packaging Equipment

Starwheel indexing may be found on a number of different packaging machines, including container cleaning equipment, liquid filling machines and certain capping machines.  Different starwheels on different machines may serve one or more purposes, from simply separating containers on a labeling machine to acting as the heart of the packaging process on a monoblock system.  Though not always a necessity, starwheels can add efficiency and reliabililty to a great number of applications.

Normally, a starwheel is comprised of a solid plastic wheel with pockets machined into the wheel at given intervals to hold the specific container being used on a project.  Indexing is one of the most common uses for a starwheel, and can be found on a number of different machines.  For example, a starwheel may be used to index a pre-set number of containers into a rinse or fill area with each cycle run by the machine.  The starwheel will rotate to release only the pre-set number, which will usually equal the number of rinse or fill heads on the machine.  Once that number has been released, the starwheel locks into position while the fill or rinse completes.  This process is repeated throughout the production run.

So while indexing containers in and out of a rinse or fill area, the starwheel also serves as a counter for bottles or containers run.  This means that a rinsing machine or filling machine using starwheel indexing can also tell you the number of containers run during a single day, a production week or even an entire month.  This is a simple way to measure efficiency from one set period to another and can assist in pinpointing areas that need improvement.

On some machinery, the starwheel will act to simply separate bottles to allow for the consistent functioning of a packaging machine.  This is, essentially, indexing of a single bottle by the starwheel.  A labeling machine, for example, may use a starwheel to create a gap between bottles, ensuring that each bottle receives only one label.  This separation also fights against mislabeling and wrinkles that may be caused from excessive back pressure on the bottle to be labeled.  The labeling machine starwheel will take one bottle and present it to the labeling equipment.  Once the label is applied, the bottle will be released along the conveyor to the next packaging stage.

Finally, starwheels can assist in positioning bottles for specific applications.  For example, an automatic chuck capping machine will use an intermittent (stop and go!) starwheel to correctly position bottles and caps under the chuck capping head.  Once in position, the starwheel stops, the chucks descend and the caps are tightened into place.  The starwheel will then begin to move once again, stopping when the next set of bottles and caps are correctly positioned.  

Intermittent starwheels can also act as the heart of a monoblock packaging system.  Working just like the automatic chuck capper, a monoblock system will use an intermittent motion starwheel to position bottles for packaging functions.  Unlike the chuck capper, the monoblock system may consist of a liquid filler, capping machine, plugger, labeler or any other number of packaging machines.  The starwheel allows for a number of different packaging processes to occur within a very small footprint.  Monoblock systems are especially popular with vials, ampules and other smaller containers.

If you would like to learn more about starwheels, indexing, monoblock systems or packaging machinery in general, please do not hesitate to call and speak with a packaging specialist today.  The toll free number is 1-888-393-3693.