Ceramics or Plastics? Both?: A Composite Material Closes the Gap between Ceramics and Plastics for Drainage Elements

摘要

The advantages of drainage elements made from ceramics are obvious. They have been established for many years in high speed paper lines such as for tissue paper. Only the very high cost, the elaborate handling and the risk of breakage represent disadvantages of "pure" ceramic solutions. By contrast, conventional plastics used in the forming and drainage section do have their justification in lower speed paper machines. The development of plastics used in paper machines was for quite some time not reflecting the dynamic development in the paper industry with increased output and line speeds of newer generation paper machines. UHMW-PE (Ultra High-MolecuJar Weight Polyethylene), the most well known plastic material used for forming and drainage elements, was developed in the 1950s and has inherent properties such as high wear resistance and very good sliding properties. However, the material has not been adapted to increased requirements and only been slightly changed over the past decades. In some areas modified UHMW-PE materials with M0S2 (Molybde-numdisulphide) as solid lubricant, cross-linked versions, materials with micro glass beads as additives were introduced with the intention to prolongate the life time of the material. To some extent improvements were made, however, the effect over standard UHMW-PE was rather limited!