Parts and elements, made wholly or partially of ceramic materials, namely, bushes, valve discs and foam filters for machines, used in chemical, food, textile, electro-technical and cellulose industries;ceramic filament guides for machines used in the textile industry; ceramic extrusion cores for machines used in the chemical industry, namely, in ceramics industry; ceramic machine parts, namely, cyclone separators and ceramic cones used in the paper and cellulose industries;welding machine par...