INCREASED CASTING QUALITY + DECREASED OPERATIONAL COSTS
Flexsil® and Cerra-Flex® refractory cloth filters serve dual roles in their ability to effectively filter molten metal and to provide a proficient and cost-effective method for de-risering and runner segmentation.
The increase in casting quality comes from filtering out the slag and dross that forms in molten metal during the casting process, increasing end-casting machinability while simultaneously reducing the casting line scrap rate. Flexsil Silica cloth traps impurities using a method uniquely different than that of competing ceramic filters. When molten ferrous metals contact the cloth surface, special coating additives decompose to instantly form a continuous film of Fayalite (Fe2SiO4). This Fayalite coating becomes soft and viscous at high temperatures to entrap even micron sized inclusions as they pass through the filter. For Magnesium treated ductile iron, the Fayalite coating absorbs Magnesium reaction products (inclusions) contained in the molten metal, and forms lower melting solid solutions on the surface of the Silica fibers. This helps to trap inclusions on the filter surface, especially the Magnesium dross, sulfides and silicates that are formed by the MgFeSi nodularizing treatment. Conventional ceramic filters are unable to capture molten metal impurities in this manner.
Decreased casting operational costs can be achieved through a drastic reduction of time and effort usually required for riser removal and runner segmentation. By placing small cut pieces of Cerra-Flex at both the riser casting contact and in various locations along lengthy runner systems, the traditional need for production line personnel to manually remove the risers and runners using cutting saws and torches after the casting has cooled can be eliminated. These residual components are instead easily knocked off or come apart by themselves during the shakeout process.