Continuing our packaging automation blog series, we come to the subject of carton identification. Once we have determined the optimal carton size through the cartonization process and erected a carton via the appropriate carton erector, the next step is to assign a unique number to each carton as it enters the automated packaging line. This ensures that we can identify and track each carton through the packaging process and is a critical step to ensuring 100% accuracy in the automated order fulfillment process.
Being able to identify cartons enables us to know what each carton is carrying throughout the automated packaging process. It ensures that at each process along the line, the carton used to fulfill a particular order is properly identified, which in turn ensures that the appropriate inventory item(s) is placed in the carton, the correct packing list is inserted, the right shipping label is applied, and any other collateral being added to the order is done so without error.
Without proper carton identification any downstream processes could be compromised with catastrophic consequences. Putting the right item and packing list in a carton isn’t enough if the shipping label is swapped with another order. That translates to two displeased customers, not just one. Without carton identification, it’s also possible to produce the dreaded FIFO (first in first out) packaging error consequence where every shipment for a period of time is “shifted,” creating errors to all customers for however long it takes to discover the problem.
Avoiding problems and ensuring accuracy is accomplished by assigning a unique number to each carton produced via a bar code. This is referred to as a “license plate number or LPN.” It distinguishes each shipment for another. There are several different ways to create this license plate:
1. Purchase cartons with a preprinted serial number either printed on the corrugated or with a label pre-applied to the carton.
- Advantage: No capital cost to produce license plates.
- Disadvantage: Potential for errors in sequencing from suppliers and poor quality in imprinted bar codes. Expensive per unit cost.
2. Print on the carton as it is leaving case erector with an ink jet printer.
- Advantage: Low capital cost, low per unit cost.
- Disadvantage: Little control over bar code quality due to bleed-through on corrugated, which could lead to reading errors.
3. Apply pre-printed license plate labels with a label applicator as cartons exit the case erector.
- Advantage: Low cost label application equipment. Ability to specify bar code quality.
- Disadvantage: Not able to customize label on the fly.
4. Print and apply labels as cartons exit the case erector.
- Advantage: Ability to customize labels and control quality.
- Disadvantage: Higher initial capital cost.
While every application has its own unique requirements, our recommendation is to stay away from options numbers 1 and 2 and consider 3 or 4. Both options 1 and 2 can be potentially error prone and, subsequently, become labor intensive. Low quality bar codes and out-of-sequence license plate numbers require excessive labor for exceptions processing — and if your exceptions handling techniques are lacking in any way, out the door quality will suffer.
Options 3 and 4, on the other hand, ensure high quality bar codes, reducing the potential for errors. The decision to apply preprinted labels versus printing and applying customized labels depends on the overall line configuration. We can help you decide which carton identification configuration is right for your packaging automation operation and help you financially justify the entire system.
The goal of a packaging automation line should not be to simply automate the packaging process. It should be to create perfect orders for your client. Effective carton identification is a critical step toward achieving perfect order quality from your packaging automation line.