Wednesday 14th September 2022 Customer Case Study REDUCING METAL EXPOSURE HFI WITH LINE FED AUTOMATIC ENAMEL RATER CHECKS Coating problems in 2-piece canmaking can have a major impact on the efficiency and cost effectiveness of a can making plant. It’s not uncommon for plants to hold multiple pallets of finished beverage cans due to issues spotted during quality control production checks. With the current increases in costs of raw materials, energy and personnel, which are permeating throughout the world economy, combined with the difficulties of keeping plants running during a pandemic, reducing these inefficiencies has become even more pressing. Decreasing the number of pallets that are required to be ‘Held for Inspection’ (HFI) is paramount. There are many potential causes of metal exposure during the DWI process. These include poor gun coverage, gun mis-fires, or low and non-spinning cans at the lacquer spray machines (LSMs), washer contamination which prevents lacquer adhesion, and scratches caused by the necking process. Wherever the problem originates, prompt enamel rating test are imperative so that any cans with high milliamp (mA) readings are identified quickly and corrective actions can be taken. Failure to do so will cause a backlog of cans that either need scrapping or re-spraying. Although re-spraying may be more economically viable than scrapping in terms of material costs, this does create considerable disruption, extra work and production time lost. Of course, if quality control fails to pick up the defective cans at all, the consequences could be substantial and costly. The advantages of automatic enamel rating is already being seen by one of our customers in South East Asia who has recently installed a line-fed Sencon Master Series™ Enamel Rater, that automatically samples cans for test from two production lines off the mass conveyors after the necker. The system samples around 8 random cans every 10 minutes, with results being relayed in real-time. This continuous, consistent and fast checking has seen the number of pallets held for inspection (HFI) reduce from 10 to just 2 pallets.Tim Yeates, Sencon's Far East Sales Manager AUTOMATIC CHECKING Having manual enamel rating gauges after the IBO (LSM checks) and the necker (finished can checks) will certainly identify any potential coating problems. However, purely relying on manual enamel raters is susceptible to operator fallibility. Operators can influence the results that are reported from enamel rating tests. They can also become side-tracked by other tasks on the line, causing gaps in the checking process and delays in the inputting of test results into the plants SPC (Statistical Process Control) system. Also, failure to check test variables such as electrolyte age and strength adequately can also impact on results returned. Whereas an automatic enamel rater provides repeatability and reliability, with checks done continuously and consistently. Regular and timely results are sent directly to the plant SPC system, enabling any high metal exposure issues to be caught early. THE SOLUTION The Sencon Master Series™ fully automatic Enamel Rater (porosity tester) is a flexible, multi-lane capable gauging module that offers a feature rich environment which integrates fully with other gauges from the Sencon Master Series™ range. As an alternative to the feature-rich Master Series™ gauge, Sencon also offer the simplified and compact PG5600 automatic enamel rater which offers many of the advantages of our Master Series™ Enamel Rater, but with a much smaller footprint and at an attractive price point. Both gauges are able to measure metal exposure consistently on modern, high-speed lines, allowing early intervention and rapid adjustment should a problem arise. They constantly check their own operation to ensure that tests are accurate and reliable. Electrolyte concentration, fill level, and many other variables are continuosly monitored, so users can be confident that the same reliable test quality is maintained day and night. With this test consistency, any trends or problems are identified quickly, allowing corrective action to be taken before excessive HFIs or scrap are generated. With the addition of OPC-UA functionality our Master series™ systems are now able to communicate with a plants OPC-UA compatible SCADA system allowing automatic intervention on the line if a problem is detected. CONCLUSION The feedback we have received from customers has shown proven benefits of installing automatic enamel raters within the canmaking process. The ability to catch problems early is proving to be a real game changer in the manageability of metal exposure and can easily result in lower overall costs, improved production efficiencies and a reduction in customer complaints. Integrating automatic enamel raters such as the Sencon PG5600 or Sencon Master Series™ is the best and simplest way to ensure these improvements are realised and more importantly, sustained. For more information please contact your regional Sencon office or agent. Fully AutomaticEnamel Rater Master Series™ The Master Series™ fully automatic enamel rater is a highly flexible and cost effective solution for automatic enamel rating (metal exposure testing).Click for more AutomaticEnamel Rater PG5600 The PG5600 is a simple, low cost and compact automatic enamel rater that is ideally designed for placing next to a palletizer, on mezzanines or in the spary area.Click for more