VISCOPRO 2100 DI CAMBRIDGE VISCOSITY
OPZIONI PER MISURARE LA VISCOSITÀ Ogni vernice ha una caratteristica curva temperatura-viscosità. Se la temperatura di esercizio e la viscosità della vernice sono note, la TCV consente all’operatore di stabilire facilmente se la percentuale di sostanze solide è corretta, alta o bassa indicando anche quali correzioni siano necessarie. Per questo motivo, un metodo di misura che includa direttamente la TCV è spesso preferito. La corretta gestione del processo di verniciatura, che
Tra i diversi metodi utilizzati per misurare la viscosità
garantisce gli spessori desiderati, implica il controllo
delle vernici, il metodo a “tazza di deflusso” è quello
e l’eventuale correzione dei parametri operativi e del-
più tradizionale. Gli svantaggi di questo metodo sono la
le materie prime, con particolare attenzione a quelle
scarsa consistenza e la bassa ripetibilità. Al contrario, la
ad alto contenuto di solidi fatte ricircolare. La verifica della viscosità consente il controllo delle materie prime e la compensazione dell’effetto della temperatura su di esse. Dal momento che il controllo completo della temperatura dell’impianto spesso non è fattibile, la compensazione termica della viscosità (TCV) fornisce un modo efficace per regolare queste variazioni dovute al cambiamento della temperatura. Il raggiungimento e il mantenimento della viscosità ottimale è pertanto sinonimo di efficacia ed efficienza dell’impianto.
ENGLISH Version
A solid and precise tool to control viscosity even for most difficult applications VISCOPRO 2100 BY CAMBRIDGE VISCOSITY, A USA BASED COMPANY MANUFACTURER OF LAB AND PROCESS ANALYZERS, AND DISTRIBUTED BY SRA INSTRUMENTS, IS A LAST GENERATION VISCOMETER WITH EXCLUSIVE FEATURES
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ISCOpro has very precise, reliable and self-cleaning sensors that ensure product quality, image clarity and good resolution, correct and uniform film thickness and optimization of processing speeds, assuring smooth coating and printing processes, reducing wastes and improving production of inks, varnishes, glues and coatings. For very complex fluids the correct viscosity is a fundamental requirement to provide a constant quality of the final product, maintain the equipment and op-
timize the use of materials. The advanced inline or immersion sampling sensors of VISCOpro 2100 are available in a variety of sizes for installation in any production environment. The tool is distributed by SRA Instruments, directly present in Italy and France, that operates in the field of research, development and customization of analytical solutions dedicated to environmental, food, petrochemical and energy areas. SRA is one of the most important European Premier Solution Partner of Agilent Technologies on whose
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instrumentation GC, GC-MS, LC, LC-MS and FT-IR the company builds its own solutions. COATING VISCOSITY CONTROL GIVES HUGE BENEFITS FOR Even though raw coating materials are perfect when they enter a converter’s plant, they usually don’t stay that way for long and deteriorate during use. Tipically the failure mechanism is simple. As a thin layer of coating material is deposited on a roller drum for coating, it is exposed to air often at elevated temperatures. This is ideal for evaporation to occur. Then the coating is squeezed against other rollers and ultimately against the targeted material itself, which further concentrates the solids in the material on the rollers. High-solids material is then recirculated in the applicator pan and day tank. To control the coating process and consistently achieve the targeted coat weight, the residual recirculated coating material high in solids must be refreshed. Viscosity control allows this refreshment to be managed ef-
fectively, but proper viscosity control requires compensation for temperature effects. This is due to the significant impact that temperature has on viscosity and the fact that temperature changes are common in many coating operations. Because full control of plant temperatures is frequently not feasible, temperature-compensated viscosity (TCV) provides an effective way to adjust for variations in process temperatures. OPTIONS FOR MEASURING VISCOSITY Each coating has a characteristic temperature-viscosity curve. If the running temperature and coating viscosity are known, TCV allows the converter to easily know whether solids are high, low or just right. TCV also indicates what corrections are needed. For this reason, many converters are choosing a method that directly incorporates TCV. Of the various methods for measuring coatings, the cup method is the traditional way to monitor viscosity. The drawbacks of the cup method are
