Fast, safe, reliable inspection of containers and labels is becoming more difficult to accomplish manually as food, pharmaceutical and other manufacturing firms seek continued increases in quality, compliance with standards and regulations and to brand image and protection. Still, the ability to justify the cost of automation is critical where pockets of manual operations exist.
Compared to manual inspection, automation can provide more accurate, validated data for 100% of packages moving down a line, and provides a grater probability of catching and removing every defect from the production stream.
Manual vs. automated inspection
Manual inspections typically rely on stops, starts, breaks and/or end-points in a lot or packaging run, Jeremy Opperman, PE and business unit manager with engineering and automation services firm Clarke Engineering, Indianapolis, explained to attendees of a session at the 2012 Pack Expo in Chicago.
While the U.S. Food and Drug Administration does allow manual inspection, it can carry cost and risk, compared to a system where 100% inspection is performed. A 100% inspection could be in reality more of a 200% inspection in light of the time, slower speed and redundant supervisory steps involved.
Beyond just automating inspection, Opperman highlighted one of the latest technologies, which he said improved upon prior laser and image-based sensors, which have traditionally been limited to detecting relatively "grossly skewed" defects such as caps on bottles or stoppers on vials.
In many applications, Lewis said the technology can cost-effectively prevent mislabeling errors, enhance compliance with standards and regulations and improve quality by performing functions including:
- Confirming package/product match, lowering the risk of a recall;
- Reducing scrap by detecting wrong or mislabeled products early in the production process;
- Checking for torn or missing labels, which is critical to the packaging process;
- Reading 1D and 2D codes, enabling products to be tracked and traced through manufacturing;
- Verifying label printing integrity, to ensure a positive brand image on store shelves;
- Detecting damaged products that result from operations such as cartoning;
- Checking date code presence, ensuring that an ink jet printer is functioning properly;
- Performing date/lot code OCR and OCV, verifying that product information is correctly printed and that labels are placed onto the right products;
- Checking for roundness, for enhanced brand image;
- Gauging, without a telecentric lens.
On the cost justification for applying Cognex' OmniView technology to the inspection of cylindrical containers, Lewis cited a real-world example in which a supplier of pre-printed pharmaceutical labels made a subtle error in Data Matrix patterns. If allowed into the distribution chain, the error would have subject the pharmaceutical customer at risk of fines from the US FDA and a potentially costly recall. "The production manager's estimate was a one-time savings of at least $800,000 dollars, making time to ROI less than one calendar month," Lewis said.
Opperman's comments to Pack Expo attendees was in agreement; he said that even if an automated system costs significantly more than a manual operation up front, the added cost of technology "may be justified by one occurrence of a major quality deviation or recall."