Packaging Machinery - Conveyor Questions

Conveyor systems are truly the lifeblood of a packaging system, responsible for circulating the components necessary - product and package - to complete the packaging process.  Choosing the correct conveyors for the specific project will ensure that production demands are met consistently and efficiently.  While each project will have unique needs, there are some basic conveyor questions, discussed briefly below, that every packager should answer before choosing a conveyor system for his or her project. 

One characteristic that separates conveyors into two distinct categories is the power used to move the products being transferred.  Motorized, or power, conveyor systems will not require any type of manual assistance to move product once they are on the belt.  Automatic packaging lines use power conveyor systems to move containers from the rinsing machine to the liquid filler to the capping machine and so on.  Without the power conveyor system, manual labor would be necessary to move containers from one packaging machine to another, defeating the purpose of the "automatic" system.  However, packaging processes using less than fully automated machines may choose non-power conveyors for some or all of the packaging processes.  For example, if filling, capping and labeling are automated, a power conveyor system will run bottles through these three machines, while the packing of the product may be done manually.  In these situations, non-power conveyors such as roller conveyors and skate conveyors, may be used to accumulate product, pack bottles into boxes or for other processes to get product ready to ship.

As we touched on when discussing filling machines, choosing the proper construction material for a packaging machine can increase the useful life of the machine.  Conveyors can be manufactured using a variety of materials from aluminum to stainless steel to HDPE and other plastics.  Though ideally the product would never touch the conveyor system, in the real world accidents happen.  Drips, leaky bottles and spills can all lead to product on the conveyor or conveyor components.  For many products, these issues are overcome by simply cleaning the conveyors on a regular basis.  Other products can have severely detrimental effects on certain materials.  Again, the most common situation arises from harsh chemicals, bleach or acid products.  These materials will eat away at stainless steel conveyor systems should drips or spills occur.  Using HDPE to construct conveyors for harsh chemicals lengthens the life and usefulness of the packaging line as a whole.

The design of the conveyor system really consists of two separate parts.  The first can be referred to as the construction design of the system.  Sanitary style conveyors allow for easy washdown of the system at the end of the product run and help to keep the entire process free from contamination.  Low profile conveyors help move products through tight spaces and fit under and around packaging machines. Other construction designs are available to meet the unique needs of each packaging line.  The second aspect of design can be thought of as the layout design of the conveyor system.  Will the conveyors run in a straight line or will space restraints require curved conveyor sections?  Some layout designs may even take advantage of the vertical space available at a packaging facility.  The line layout of the conveyors will take into account the space available, the packaging machinery to be used, and the loading and shipping areas of the facility, among other factors. 

The necessary height, width and length of the conveyor system must also be taken into account.  Most automatic packaging machines will include power height adjustments (think of the nozzles on a filling machine or the tightening disks on a spindle capper).  These height adjustments will have upper and lower limits.  The height of the conveyor system must ensure that the range of bottles or other containers being run on the packaging line will not take the packages outside of these limits.  The width of the conveyor system simply needs to accommodate the range of containers being run by the packager.  The length of the system must allow space for all of the packaging machines and/or manual labor functions present on the line.  Creating a line layout will normally ensure that the necessary space is available and that the height, width and length are properly configured.

Most conveyor systems are built with a maximum weight capacity that far overreaches the actual weight that will ever be supported by the system.  However, large containers or heavy product running at high speeds can occasionally create heavy weights.  Using the right material, motors and supports in these situations will ensure that the conveyor system does not lag or suffer abnormal wear and tear from excessive weight.  The packager should always be aware of the maximum weight capacity and check that each of the package and product combinations run on a packaging line do not exceed these limits by practicing some simple math.  While this burden will usually be taken on by the manufacturer at the time of building the system, new products, new containers and even higher production will warrant recalculating the weight capacity of the conveyors.

A variety of conveyor belting is available for almost any conveyor system.  Standard polypropylene or delrin belting will suffice for a majority of packaging lines.  However, unique products call for unique belting material.  Some products require a hot fill, meaning that the product must be heated to run through a filling machine.  In these situations heat resistant belting should be used on the conveyors.  Flammable products can use anti-static conveyor belting to avoid sparks.  The conveyor belting should be matched to the specific needs and unique characteristics of each packaging project. 

Finally, the conveyor system should easily integrate with other packaging machinery, both at the present time and in the future.  Almost all individual conveyors can be connected to existing lines.  Transfer plates or other connections can be used to extend existing conveyor lines.  Transfer turntables can be purchased to allow for ninety degree turns on a conveyor system.  The construction, design, height, width and length should also allow for future equipment - filling machines, capping equipment, labelers, etc. - to simply roll up to the conveyor and begin packaging product.  A packager can protect their line from becoming obsolete by asking about the ability to integrate the conveyor system with other equipment.

 

As with our discussion of both filling machines and capping machines, the caveat must be that all packaging projects differ in some respect.  While the above considerations will almost always be relevant when choosing a conveyor system, each project will also produce unique considerations based on the product, package, production demands and the needs and desires of the packager of that product.