"Dynamica" pressure screen seals produced from high quality materials such as ;
Pressure screening is nowadays the most widely used method for cleaning pulp, its success being based on the invention of profiled screen plates, which give better capacity per unit screening area than do smooth screen plates (Winkler & Kelly 1994). Pressure screens are also used for the fractionation of pulps, which can be considered to be a specific application of screening (Borschke et al. 1998).
There are several configurations for pressure screens devices. A design which corresponds closely to the principle employed in this work is illustrates in Fig.
• Silicon Carbide
Silicon Carbide is the only chemical compound of carbon and silicon. It was originally produced by a high temperature electro-chemical reaction of sand and carbon. Silicon carbide is an excellent abrasive and has been produced and made into grinding wheels and other abrasive products for over one hundred years. Today the material has been developed into a high quality technical grade ceramic with very good mechanical properties. It is used in abrasives, refractories, ceramics, and numerous high-performance applications. The material can also be made an electrical conductor and has applications in resistance heating, flame igniters and electronic components. Structural and wear applications are constantly developing.
• Resin-Impregnated Carbon Graphite
Resin-Impregnated Carbon Graphite contains a chemically resistant resin offering superior performance in a wide range of media. This resin-impregnated carbon graphite provides exceptional friction and wear properties in pressed-to-size configurations for high-volume applications. Resin-impregnated carbon graphite blanks for companies that need to machine mechanical seal primary rings, radial bearings, thrust bearing, case wear rings, or pump vanes on an emergency basis. The material has excellent lubricating qualities when running in low viscosity liquids in the temperature range between -400 ํF and over 500 ํF. Mechanical seal rings, bearings, and vanes machined from these blanks are impervious to high-pressure liquids. The material is dimensionally stable so that mechanical seal ring faces can be polished to one Helium light band flatness, and the flatness is retained indefinitely. The material is chemically resistant to almost all liquids except extremely strong, oxidizing acids and alkalis.
• Antimony-Impregnated Carbon Graphite
Antimony-Impregnated Carbon Graphite combines the frictional properties of carbon graphite with antimony metal to build a high-strength, high-performance material with lubrication and better thermal and electrical conductivity to dissipate heat away from seal interface.
* For the other configuration of materials also available on request.