Central Desiccant Flexible Dryer type DFD 1700 is equipped with frequency inverter for variable flow control according to line consumption. Schrรถder, head of the extrusion department at Utz is enthusiastic: "The Labotek system provides us with not only dry material for the extrusion thus we can operate most of the whole system by the use of residual heat, which was not previously used. This is an active contribution to protection of the environment!" The vacuum for the feeding is made possible by maintenancefree Labotek vacuum circuits with frequency inverters. The complete conveying and drying system has a control system based on the Siemens S7 systems with ASI Fieldbus.
The vacuum circuits are each equipped with a central, selfcleaning filter. The stainless steel vacuum receivers are fitted with stainless steel screens, where dust is separated and led to the central filter. The advantages is that you do not need high-maintenance filter cartridges and get a high production quality and reliability. Each of the extruders is fitted with a Maguire gravimetric batch mixer on a steel platform. Each mixer is equipped with a touch screen control and can be operated locally. In addition, all Maguire mixers are connected via the intranet of the company Utz, with
the Maguire G2 Supervisory System. This permits remote control of each individual mixer. All operating data, recipes and material consumptions are stored on a separate server, via the LAN-connection of the Maguire WSB-batch mixer. The use of gravimetric Maguire WSB mixer provides a high dosing accuracy and the precise amount of master batch in consideration of inline recycled material for grinding and homogenizing in the mixing chamber. For the operator, it is of course very important that the entire system is equipped with a simple
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