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Double suction disc
Double suction disc
Keywords: Wilhelm Niemann, Fullbrook Systems, Dispersions
The new double suction disc from dissolver manufacturer, Wilhelm Niemann GmbH, comprises two saw-toothed discs with different diameters and tooth configuration. This disc is believed to be a significant advance over the conventional single disc that is currently used throughout industry.
The additional toothed disc has a large central hole that induces a very strong suction effect. This reportedly avoids excessive heating of the product during the dispersion process, and ensures optimum mill-base viscosity throughout the dispersion period. The suction effect has not only a positive influence on the dispersion result but it also minimizes the amount of dust. Particularly low density raw materials, such as aerosit, as well as fillers and pigments, are drawn in and wetted out in an extraordinarily short period of time. Tests are reported to have shown that, in certain applications, the actual energy consumption is lower with a"double suction" disc than a "single" disc.
In order to achieve better dispersion results than with a conventional disc, it is an important precondition to have a highly concentrated mill base with an optimised formulation. If the mill base viscosity is too low, turbulence and splashing can have a negative effect and lead to a poor dispersion.
The batch time for the production of a high-solids wall paint (pigment and filler concentration of more than 67 per cent) with manual addition of raw materials can, it is claimed, be reduced from 2.5 hours to approximately one hour, using the Kreis-Dissolver. With solvent-based paints like white enamel, marine paints, high-solid paints, iron oxide primers and other products with inorganic and microfine pigments, it is possible to reach the final dispersion quality using a double suction disc. The disc also offers the possibility of increasing the pigment concentration in the mill base. This improvement in dispersion quality means that the need for any further processing on a bead or triple roll mill is frequently eliminated.
Details available from Fullbrook Systems, Tel: +44 (0) 1442 876777; Fax: +44 (0)1442 877144; e-mail: email@example.com