Process Filters with MINIMESH® S Metal Filter Cloth
Haver & Boecker manufactures metal wire cloth for various applications and brings it individually into form. Amongst others, for preparation of drinking water, sea water, ballast water as well as waste water. The often multi-layered structure of these filters and the fabricated parts as well as the production process used are based on specifications provided by the customer, combined with the commitment to quality of Haver & Boecker. The filter-layer used is a square-mesh or a MINIMESH® S-filter cloth dependent on the desired pore size and required flow capacity.
MINIMESH® S metal filter cloth from Haver & Boecker is characterised by problem-free further processing, simple cleaning and a very long service life. Its geometry and therefore its filter structure is absolutely uniform over the whole filter surface in contrast to that of non-wovens made out of paper, plastic and metal fibres.
The metallic materials used to manufacture MINIMESH® metal filter cloth makes it extremely resistant to chemical and physical influences. The predetermined characteristics are retained even after processing to filter candles, cylinders, stamped parts or application-specific three dimensional forms. Therefore industrial filtration processes continuously run in a stable, precise, energy efficient and overall economic manner.
Real particle sizes and their evaluation methods
In the area of filtration the term “filter fineness“ is often quoted as a measure of the maximum size of a particle which can pass through a filter medium. However, the fact that there are many factors influencing the filter fineness of a medium is often left unrecognised. Thus, for example, the particle form, measuring and evaluating methods as well as ambient conditions can influence the particle determination. It is for this reason that Haver & Boecker views the largest geometrically determined pore size (Xmax) which can still just pass through the fabric for an optimal filter design.
In cooperation with the Institut für mechanische Verfahrenstechnik at the University of Stuttgart, Haver & Boecker participated in the development of the mathematical formula which is the basis for determining the geometric pore, part of the AVIF projects. A geometrically determinable wire mesh is also qualified by Haver & Boecker on the basis of the glass bead test which has established itself as across a number of branches as the authoritative test procedure for the filter cut point. This is the way in which customers can make comparative evaluations of different fabrics and compare them.
Matrix of the different MINIMESH® S-filter fabrics
MINIMESH® S-filter fabrics are used for filtration, fluidisation, drying, screening as well as for different thermal, electronic and acoustic applications. This variance also demonstrates the vast range of different types of woven wire cloth, which Haver & Boecker developes and manufactures in-house. It is not only the particle properties such as the geometrical pore size which are decisive for the selection of a filter cloth, but also good flow characteristic accompanied by a low pressure drop. The pressure drop coefficient Zeta, which is very meaningful in this context, should also be calculated. The following applies: the smaller the value Zeta, the lower the pressure loss.
MINIMESH® HIFLO-S twilled weaves from Haver & Boecker achieve a very high number of pores per a given surface area. The most recently developed HIFLO 10-S is particularly suitable for water filtration. This, above all, for finest particles with a geometrical pore size of 10 µm, allows a high flow capacity and has a long service life due to the low blocking tendency and the strong compound fabric.