TUBULAR PRODUCT, METHODS FOR ITS PRODUCTION AND USE (VERSIONS) Russian patent published in 2002 - IPC

FIELD: tubular polymeric product restoring its geometric dimensions at heating, methods for production of the product and methods for the use of the product for joining of two elongated objects. SUBSTANCE: according to the first modification, the method for production of a tubular product consists in spiral winding of polymeric sheet with intermolecular bindings restored at heating with formation of a tubular configuration, containing two or more lapped intersecting layers of a spirally wound sheet. The polymeric sheet contains polyethylene. Then the wound sheet is positioned around the supporting spindle and heated to a temperature sufficient for direct fusion of the adjacent lapped intersecting layers of the sheet with intermolecular bindings. According to the second modification, the method consists in spiral winding of a polymeric sheet with intermolecular bindings containing polyethylene that is stable at heating with formation of a tubular configuration, containing two or more lapped intersecting layers of a spirally wound sheet. Then the wound sheet is heated to a temperature sufficient for fusion of the adjacent lapped intersecting layers of the sheet with intermolecular bindings, and the fused layers are expanded outside due to which the product becomes restorable at heating. EFFECT: strengthened tubular product with a wall thickness of at least 2.2 mm containing a spirally wound polymeric sheet with intermolecular bindings, containing polyethylene, whose lapped intersecting layers are directly fused together. 3 cl, 10 dwg