Food quality and safety is something that we tend to take for granted when we visit our local grocery store or supermarket. Whilst we may often scan read the sell by or use by dates on fresh produce packaging, when it comes to canned products we will invariably pick the can from the shelf and place it straight into to the basket as we have come to place great trust in products of this type. At the heart of the quality, consistency and safety of some of the most widely recognised canned food products here in the UK are the high-speed machine vision systems designed and built by Warwickshire based InterVision Global.
Following years of experience in developing and deploying machine vision inspection systems within high-volume canned food production facilities, InterVision Global has now released their inline CanCheck inspection system. Comprising nine individual systems, which can be used individually for specific tasks, or combined to create the industry’s most comprehensive machine vision inspection system, CanCheck addresses quality issues relating to cans, labels, codes, foreign objects and much more.
To ensure and maintain the highest levels of productivity, it is essential that the inspection process starts right at the beginning of the production process. Bright stock cans entering the line need to be checked to ensure that they are within specification and do not exhibit distortion or damage which will cause issues downstream. These cans may have been transported and handled several times before reaching the line. Each handling operation provides potential for cans to be damaged or distorted significantly enough to cause production equipment to jam, impacting productivity levels due to the stoppage time required to free any out of specification items. InterVision Global’s Inline non-contact CanDamage inspection system checks the complete can circumference for damage in the form of dents or crushing.
The system is flexible and allows the user to determine what level of defect is acceptable and will not impact the production process. As with all of the InterVision modules, CanCheck allows thresholds to be set to ensure that only cans, which are outside of the users pre-determined threshold, are rejected from the line.
Identifying foreign objects
A key part of guaranteeing food safety and product integrity is preventing and detecting foreign objects in the can prior to filling. As it is not uncommon in high-speed manufacturing for objects and dirt to fall inside cans, it is essential that each can is checked before product is introduced. InterVision’s FODcheck system inspects the inside of the can just prior to entering the filling station. Any cans with foreign objects or dirt are safely and reliably removed from the line. The capability and the size of the foreign object detected is determined by the resolution of the camera selected and can of course be tailored to the specific application.
As part of the manufacturing process, the filled, yet un-labelled bright stock cans are marked with a product code and are also date-time stamped for traceability. This allows ongoing identification of the product variant. It is not uncommon for filled bright stock cans to be removed from the line prior to labelling and stored before being fed back into the line to fulfil a specific customer order. In these instances, and because of brand protection and allergy concerns, it is essential that the can and its contents correlate with the labels being applied, to avoid batch mix and mislabelling.
At typical production line speeds, which can be up to 1200 cans per minute, it is impossible for an operator to verify every can has the correct code; however, InterVision Global’s CanCode system can provide the reassurance that only the correct cans enter the labelling system.
CanCode will read the code regardless of its position and orientation. It is also tolerant of the typical variances that occur with the inkjet marking process used to generate the codes. CanCode can deal with differing code scale, skew, stretch and inter character spacing as well as different levels of contrast and coloured inks. This ensures that any incorrect product is quickly identified and removed from the line, whilst using CanCode’s high performance algorithms to keep false rejects to a minimum.
With the correct can going into the labelling system it is then essential to verify that the correct label will actually be applied. There are potentially vast numbers of permutations on labels, and it is essential that labels are checked and verified before being applied to the can. This is achieved by reading the label “Artwork” number as it is applied. Relying on just the label barcode is not a robust process, as different territory products can share the same SKU or barcode. In addition, the barcode printed on the label does not differentiate between the varying nutritional information or language on the label. Printed on the label seam, this number must be checked before application as following this stage it may be concealed from view. InterVision Global’s LabelSure module reads the “Artwork” number within the labeller checking and verifying that each label is correct for the product batch being produced at the time. In addition to the 100 per cent check on each label, LabelSure guards against potential errors when changing products, labels or replenishing label stock within the labelling system.
Sealed for safety
It is absolutely essential that cans containing produce are sealed correctly to maintain the product integrity and guarantee safety for the consumer at the point of consumption. Following the pasteurisation and cooling processes, the concave features on the top and bottom of the can are the characteristics used to determine that the can is correctly maintaining its seal. Each can must be checked, and any that do not exhibit the correct concave profile must be rejected from the line. InterVision Global’s CanSeal system uses a clever combination of laser and machine vision technology to measure the profile of the can lid and base at production line speeds. This ensures that each and every can is checked, defective cans are identified and verified as rejected.
At the heart of InterVision Global’s CanCheck System is mvGuardian, the intuitive operator interface that runs on a central processing unit that gives the Operator visibility on all the running subsystems to view the systems run-state, performance and statistics as well as carry out troubleshooting and diagnostics.
The performance and reliability of InterVision Global’s CanCheck systems have ensured that they have become an integral part of the production process for some of the world’s leading brands. These companies trust their reputation to this technology to maintain the highest levels of quality and compliance at line speeds exceeding 1200 cans per minute.
To learn more about the CanCheck inspection system please visit www.intervisionglobal.com.