PETpla.net Insider 03 / 2016

INSPECTION 37 PET planet insider Vol. 17 No. 03/16 www.petpla.net Enhanced rejection rates on filling lines during the manufacture of beverage closures Perfect position The chuck penetration depth simulator determines the position of the manufac- tured closures in a simulated chuck of a capping machine. During the process of applying beverage closures to PET bottles, minor gradations can determine whether the closure will be grasped and placed on the bottle correctly in the fill- ing line. At filling speeds of up to 100,000bph, even slight variations at the closure can result in unacceptably high rejection rates. In any economically sensible manufactur- ing process, the production process for beverage closures relies on manufacturing tolerances, and therefore the chal- lenge lies in differentiating between variations within the tol- erance limits and those outside. For this purpose, Corvaglia Mould AG has developed and launched what is known as a chuck penetration depth simulator. Corvaglia analysed the causes of high rejection rates in filling systems and determined that different com- binations of a wide variety of critical characteristics (various dimensions, deformations, irregularities in the raw materials, colours, etc.) can result in an unacceptable application. As the core element of the newly developed validation method, the chuck penetration depth simulator determines the position of the manu- factured closures in a simulated chuck of a capping machine. If closures are positioned too deep in the simulated chuck, this could break the bridges of the tamper-evidence band. Closures that protrude too far out of the chuck can result in insufficient centring, which in turn results in cocked closures or prevents closures from being applied. Using the chuck penetration depth simulator, manufacturers can quickly differentiate between closures that can be correctly applied and closures that cannot – and they can now do so during production of the closures, and not, as previously, when the clo- sures are being applied. Thanks to this pre-application testing, potential rejects amount to only a few individual closures, whereas previously, fin- ished, filled bottles had to be disposed of. The new tool from Corvaglia is intended to reduce costs and con- serve resources. Minimising rejection rates In addition, the chuck penetration depth simulator can also be used for in-process control in order not only to minimise rejection rates, but rather to ensure that rejection is prevented in advance. In production line trials in filling systems that had unaccept- ably high rejection rates, Corvaglia has been able to prove that the use of the chuck penetration depth simulator resulted in a reduction of these rates to below 50ppm (= 0.005%). The tool is already in use today at Corvaglia’s manufacturing locations in Switzerland and Mexico, as well as at selected partner companies. www.corvaglia.ch During production of the closures, their correct application can be checked with the chuck penetration depth simulator I NSPECT I ON S P E C I A L