Firm grip, efficient packing
The end of line is a crucial point for maximizing the economic result of the milling plant since, if properly designed by foreseeing the best possible solutions and obviously taking into account the economic values involved, it can considerably help high productivity and decrease operating costs.
Among the more than 1,600 applications made by the company from its origins to today, one of the most recent is an end-of-line system for palletizing and wrapping with stretch film, intended for a flour production plant located in Honduras.
The application in question is intended for the milling industry and consists of a work island with 3 YASKAWA Motoman MPL160 robots, each enslaved by a packaging line designed to bundle the 25 bags of flour weighing 1 lb. each into bundles. Each robot picks up the bundles produced by its line from a roller belt and stacks them on a pallet previously placed in the loading station by an automatic feeder, alternating layers with interlayer flaps to ensure the stability of the full pallets made. The geometry and number of layers of each pallet can be defined according to specific job requirements.
The Challenge
Within each bundle, the bags are sorted into 2 rows of 12, plus a cross pack. One of the greatest difficulties in the palletizing task is related to the easy deformation of these bundles. In fact, the floury, thin, and hot contents combined with the use of small, soft bags that were not secured together made the automatic handling of these bundles extremely complex, so much so that until now the activity has always been carried out manually by operators who not only moved the bundles but also rearranged their internal contents.
The solution
To solve the problem, Ocrim developed an innovative and extremely effective solution, also making the most of the peculiarities of the bundle casing, which has microholes on the upper side. It therefore chose to equip the robots with a vacuum vacuum gripping system instead of a traditional mechanical gripper system. In this way, the vacuum makes it possible to firmly grip the outer wrapper, keep the bags inside intact and compact, and ensure precision positioning while the bundle is stacked on the pallet.
Results
The decision to rely on Yaskawa robots represents the consolidation of a partnership that began in 2017 and has already seen this division of Ocrim deploy several Motoman robots, a collaboration now well established between the two companies. "In Yaskawa we have found a partner able to provide us with the right mix of availability and expertise, always ready to support us on a technical level in development activities," explains Roberto Cagna, head of Ocrim's Palletizing division. Support in development activities but not only: another aspect that is particularly relevant in situations like these, where the application is intended to be installed in remote locations from the production factory, is maintenance. "The whole system is equipped with remote monitoring and remote maintenance systems, covering from the plc to the individual robot. But it is also critical to ensure easy access to spare parts. "The Yaskawa Group's presence in South America gives us the opportunity to guarantee our customer an easy supply route for parts and materials for any future system maintenance activities, which is far from negligible." Not surprisingly, Ocrim is already working on a second line, intended to handle another packaging format for the same customer, again using Yaskawa's Motoman robots.