| 摘要 |
The outer surface of a ferrous metal pipe is covered with epoxy or polyester resin weighing between 50 and 500 g/m<2>. Before it hardens the resin layer is covered by a wound on second layer of woven or non-woven fabric impregnated with still wet cement mortar applied to the fabric before winding. The fabric fibres may be polypropylene, polyvinyl chloride, polyamide or polyester. The cement mortar can be portland, aluminous or slag cement and, with respect to the cement, contain between 20 and 50% by weight of water and between 0 and 100% by weight of sand. The second layer is then covered with a sealing layer which can be bitumen, tar or an emulsion of resin. <IMAGE> |
