Novatronic D2 plasticity control system
For energetic reasons, the material should contain as little water as possible, since the cost of heating the dryer is directly dependent on the water content of the green bodies, and the generation of steam for use in the circular screen feeder and single- or double-shaft mixer upstream of the press or extruder costs money, too. Less water means less dry shrinkage and a host of relevant benefits and potentials. On the other hand, too little water means higher power consumption and more wear and tear on the equipment.
Poorly adjusted and excessively frequent starts, slow, large control fluctuations and even erroneous settings sometimes go unnoticed and allow too much water to be used for some length of time. Studies have shown that only substantive time histories of preparation- and shaping-process trends enable detection and rectification of bad settings. The optimization potential is determined by the quality of the current controls in comparison with the technically achievable control quality in terms of medium and maximum control deviation.
Now, though, the new Novatronic D2 system solution for preparation and shaping provides a suitable tool for controlling the moisture and plasticity adjustment processes. Where each separate unit used to require its own hardware controller, a single unit now suffices for the entire production line (pan mill, circular screen feeder, double-shaft mixer and press/extruder). The standard version of the new Novatronic D2 contains two complete control cascades and can be expanded to as many as six controllers with little ado.
With deference to increasing demand for reproducible process conditions and long-term data archiving, innovatherm integrated the time-tested Novacontrol data logging feature, hence rendering unnecessary the until now oft-employed multiple/parallel data recorders and all the attendant consumption of handling materials (paper, colour styluses,…). Now, the data is recorded digitally onto a CF card or hard disk together with sundry recipe and product data plus the entire chronology of alarms and messages. In that sense, the acquisition/requisition horizon is limited solely by the storage medium and guarantees traceability for years on end.
For analysing the stored data, both a graphic display of trends with freely selectable time horizons and a file export function into Excel-compatible files are provided.
The function range of the software feeding the Novatronic D2‘s panel PC with touch screen has been accommodated to broadened requirements. Now, process parameters from upstream and downstream equipment, e.g., belt conveyors or cutters, can be tied into the control system and driven by product-dependent target values from the integrated recipe database.
For the Novatronic D2, the hardware of the Novacontrol C humidity and plasticity controllers was replaced with globally available Siemens ET200S components. In addition to a number of other advantages, this significantly improved the flexibility of the process interface. A pair of integrated Ethernet interfaces enable tie-in to existing facility networks that can be used for calling up current data, altering recipe data or archiving any data. Consequently, remote support and/or optimization can be implemented.