A Trip Down a Typical Automatic Packaging Line

A Trip Down a "Typical" Automatic Packaging Line

Though every automatic packaging line will vary in one way or another, one can imagine a typical packaging line as a starting point for many different systems.  From this typical packaging line, changes can be made or components added to find the ideal solution for each specific project.  In order to understand the typical line, and why it will almost always be tweaked, let's put ourselves on the power conveyor system and take a trip down the line.
There exist several different ways to get bottles onto the power conveyor system.  Some systems will use a loading turntable that allows manual labor to take bottles or containers from a case and set them onto the turntable.  Once on the loading turntable, a bottle guide would force bottles to the outside edge of the turntable, where eventually the bottles would slide off the turntable and on to the take-away conveyor.  Other facilities may use a bottle unscrambler, leaving an operator to simply dump bulk bottles into a hopper.  The unscrambler then orients the bottles and sets them onto the power conveyor.  Other methods may also be used to load bottles onto the packaging line, depending on the automation level desired and the speed required.  Once on the conveyor system, it is time to visit each of the packaging machines.
In many instances, the first packaging machine to be encountered by the bottles will be a container cleaning machine.  Bottle rinsers and washers are used to remove debris and contaminants from containers before product is introduced.  Depending on the production demands and the type of bottle being used, rinsing machines can be manufactured with anywhere from two to sixteen rinse heads.  Many bottles will enter the rinse zone and then be removed from the power conveyor to be inverted over a rinse basin.  Once inverted, a blast of air, water or other solution will be used to wash out the inside of the container, the debris and possible contaminants flowing into the rinse basin.  Once the rinse is complete, the bottles are returned to the power conveyor.  The duration of the rinse can be adjusted based on the container being rinsed.  Some bottles or other containers can be difficult to grasp and, therefore, difficult to invert.  In these situations, a bottle vacuum may be used in place of the inverting rinsing 
machine.  The bottle vacuum will use special nozzles that will seal over the bottle opening, blast the inside of the bottle with air to loosen debris and then vacuum the debris from the bottle.  The type of rinsing machine used will again depend on the product, package, desired speeds and several other factors of the specific packaging project.
Once rinsed, bottles will continue down the power conveyor to the next station, normally the filling machine.  Automatic filling machines can use a number of different filling principles.  The type of liquid filler used will depend in large part on the product being run.  Thin products such as water or window cleaner will often use an overflow filler or gravity filler.  Pump and piston filling machines are normally manufactured to handle thicker, more viscous products.  These are general rules that will apply in most, but not all, packaging projects.  Like the rinsing machines, the liquid fillers can come equipped with anywhere from two to sixteen fill heads to meet production demands.  A host of options, such as diving heads, drip trays, neck grabbers and other components can be added to the automatic filler to suit the needs of the individual packager.  While product plays the largest part in manufacturing the filling machine, production demands, the package and other factors will also come into play.  Once the bottles have received the product, they will again continue their journey down the packaging line.
In many cases the fill will immediately be followed by an automatic capping machine.  As the product has now been introduced to the bottle, the package will usually take over as the main factor in choosing packaging equipment.  The type of capper to be used will depend on the type of cap being used.  A majority of bottles will use some type of screw on cap, making spindle cappers and chuck cappers the most popular of the automated capping machines.  Other closures do exist however, including snap on caps, ROPP caps and others.  Even if using a screw type cap, the variations are many, from flat to sports, flip-top and trigger sprayers.  The cap variations can also have some influence on which machine will be used for a specific project.  Automatic capping equipment will also include a cap delivery system to continuously provide the caps to the packaging machine.  Cap elevators and vibratory bowls allow operators to simply dump in bulk caps to be supplied to the machine.  As the bottles travels along the conveyor system, it will pick a cap up just before entering the capping area, be it spindles, a chuck or ROPP capping head.  
It should be noted here that, at times, a packaging system will use a nitrogen purge system between the filling and capping equipment.  A nitrogen purge system replaces oxygen - either in the bottle itself or in the head space after product is introduced - with nitrogen.  The nitrogen helps extend product shelf life while retaining product color, taste and texture.  As you can probably guess, many food and beverage products will take advantage of this extra step in the packaging process.
So the bottle has been filled with product and sealed reliably, but the trip is still not complete.  Upon exiting the capping machine, the bottles will typically move to a labeling machine.  The type of labeler that will be used will once again be determined mostly by the type of container, though other factors can play a part.  For example, most water bottles will use a pressure sensitive wrap labeler to apply a label around the bottle.  Other containers may use a simple front label or a front and back label combination.  Often times, along with the labeling machine, a coding machine will be used to add expiration dates, batch codes and other information that will change from time to time.  
Once the label is applied, the product is basically ready for the shelf and the consumer!  However, there still remains some work to be done.  As the bottle comes out of the labeling machine and continues down the power conveyor, several options exist for packing the products.  Some packaging lines may simply use an accumulating conveyor or turntable to gather products for packing.  Once gathered, manual labor will be used to pack the product into cases for shipping.  Other packaging lines will continue with automation using machines such as case packers, case tapers, shrink wrap bundlers and even pallet wrappers and palletizing machines to complete the process.  The end of the line equipment, or packing equipment, will be determined by the production demands and desires of the packager, among other factors.  
The typical packaging line, then, will usually consist of specific types of packaging equipment:  power conveyors, rinsing machines, filling equipment, capping machines and loading and packing equipment.  However, in the details lie the differences from one packaging system to the next.  How will bottles be loaded to the line?  What type of filler will be used?  Which capping machine will best serve the bottle and cap combination chosen for the specific project?  Each of these questions and many others should be answered in order to find the best possible packaging solutions for each packaging facility.