Pipes and tubes of metal; Lined and coated pipes and tubes of metal; Metal pipes with lining for protection against wear; Metal building materials in the nature of metal boards, plates, panels, plankings, slabs, pipes, inserts, castings, fittings and linings having a coating based on minerals, ceramics, artificial resins and plastics, including in combination with other materials, all for use in lining and reinforcing bunkers, silos, pipelines, conveyor chutes and channels, mixers and other s...