Superfos, a manufacturer of injection-moulded plastic packaging for food, non-food and healthcare markets, has implemented an advanced machine vision inspection system on its Randers, Denmark, production lines dedicated to containers for butter and other dairy products.
The system implemented at Superfos includes several inspection stages ensuring a 100 per cent inspection of all containers and all lids leaving the production lines. The plastic cups are inspected from up to three different viewing angles using digital FireWire cameras from Allied Vision Technologies. At the Superfos’ Randers factory, a total of 53 digital cameras are in operation as part of the inspection systems developed by TriVision, a leading Danish machine vision solution provider.
Superfos faced the challenge of ensuring a reliable, 100 per cent quality inspection and optimising costs. 'Of course, the primary goal of a machine vision inspection system is to ensure high quality standards,' said Stig Skovbo Sørensen, project engineer at Superfos. Sørensen also wanted economic benefits from the system by minimising the number of false rejects and thereby reducing waste. Another economic challenge for the inspection system was to perform quality checks at the full speed of the production line, to avoid impacting productivity.
TriVision's Packaging Inspector is a state-of-the art optical inspection system specially designed for 100 per cent inspection in the packaging industry. It can detect defects such as over-moulding in injection-moulded plastic containers and check printed labels.
For the inspection of square butter boxes, TriVision selected Stingray F-046B cameras to control material defects: two cameras are positioned below a conveyor belt and inspect the inside surface of the box as it passes above them. Simultaneously, an AVT Stingray F-201B inspects the printed artwork from above to check the correct position of the label, barcode, etc. The lids used to seal the containers are controlled on separate lines using Stingray F-201C colour cameras.
The Stingray is a highly flexible industrial camera combining a fast IEEE 1394b interface with advanced image optimisation functions (AVT smart features). The Stingray F-046 and F-201 feature a 0.4 Megapixel and 2 Megapixel CCD-sensor respectively.
Round cream cups are checked using a combination of Stingray F-146B and Marlin F-145C cameras. The Stingray F-146B camera inspects the inside surface of the cup as it passes below it on a conveyor belt, while a lateral Marlin F-145C camera checks the presence of the label on the outside surface. The lids for the round cups are controlled by AVT Guppy F-146B ultra-compact IEEE 1394a monochrome cameras with 1.4 Megapixels resolution.
'Our Packaging Inspector system detects the smallest defect but this requires a very fine tuning of the camera settings with the image processing software. AVT Stingray cameras offer a wide scope of settings for image optimisation and camera control that help us to make the most out of every single image,' commented Ole Neckelmann, managing director of TriVision.
Building on the success at Superfos, TriVision is planning several similar projects at other packaging manufacturers.
