PETpla.net Insider 03 / 2016

BOTTLING / FILLING 18 PET planet insider Vol. 17 No. 03/16 www.petpla.net Stepless volume-flow adjustment at the filling valve Flexible filling function Based on an article by Florian Angerer, Krones AG With its Proportional Flow Regulator (PFR), Krones intro- duces a filling-valve component that is said to create the preconditions for a flexible filling function. Instead of the two previously customary fixed flow rates (slow/fast), the flow re- gulator can create any flow velocity desired up to and includ- ing the level- and pressure-related maximum filling speed. Krones put the PFR to the test at the Burg Groep in the Neth- erlands: for filling vinegar, an extremely acidic liquid with a pH-value of 2.2, and prone to vigorous foaming as well. Vinegar is one of the most demanding liquids around when it comes to its commercial filling. With its pH-value of 2.2 to 2.5, it aggres- sively attacks all parts coming into contact with it, such as stainless steel, but also, and especially, the seals. What doesn’t make things any easier is its marked susceptibility to foaming, which is why vinegar is a tough chal- lenge for any filling operation. Krones was eager to take on this challenge, and test for its practical utility the PFR filling-valve component, developed specifically for handling vigorously foaming products. The Burg Groep is one of the leading companies on the global vinegar-production market. The firm manufactures natural vinegar with an outstandingly high acidity of up to (or even exceeding) 20%. The vinegars are available as ready-to-use articles for the consumer and also as a semi- finished product. In its plant at Heer- hugowaard, the Netherlands, a total of three filling lines are up and running, two of which are rated at 7,000 and 8,000 containers an hour respectively. The third line was installed by the group in 2010. From the filler to the packer, it consists entirely of machines from Kosme and Krones, and permits a maximum output of 16,000 contain- ers per hour. At present, however, the line’s speed is limited to 11,000bph, due to the existing blow-moulder. The line comprises an AirCo conveyor, a pressureless Modulfill VFJ filler with 48 valves and an integrated Check- mat F-G, an existing Kosme Star 12T labeller, a Kosme Divipack container spacer and a Kosme Flypack packer. It is used to fill a variety of vinegar-based products, both household vinegar and domestic vinegar-based cleaning agents. Proportional Flow Regulator In developing the Proportional Flow Regulator (PFR), Krones’ intention was to create a component which marries top performance to a maximum of functional dependability for the future, irrespec- tive of the boundary conditions involved. It can be combined with all commonly used metering systems, like a flow meter, a weighing cell or a short-circuit sensor. The electronic control compo- nents are installed in every filling valve for a decentralised configuration. The PFR has already undergone tests with milk, juice, vinegar, ice tea, wine, soy sauce and CSDs. As it runs off electric- ity, there is no need for any pneumatics in this system. Another option is what is called a hybrid structure, in which con- ventional pneumatic valves are com- bined with the stepless regulators. One of the advantages in practi- cal operation is that the flow velocity is user-selectable; so the machine can always be run at its maximum possible speed, thus permitting it to be optimally matched to all product-bottle combina- tions. The PFR makes rigorous use of field-proven materials: stainless steel, PTFE and EPDM, so as to comply with hygiene standards. Intelligent monitoring systems are said to ensure a maximum of functional dependability and machine availability while continual adjustment of the valve function makes for a consistently high level of filling quality. Practical test The technology was installed and tested at the Burg Groep step by step, mostly at weekends, so as not to hamper ongoing production operations. The filler, meanwhile, has been running with the PFR for more than 3,000 oper- ating hours. “Given that filling is performed at continuously changeable speeds, foam- ing is severely reduced, or even entirely prevented. The foaming problem has