Abstract: A method and apparatus for producing a curved tubular segment includes obtaining a curved external tubular element and a curved internal tubular element. The curved internal tubular element is made of a material having a resistance to wear greater than that of the curved external tubular element and has a cross section such as to cover at least part of the internal surface of the curved external tubular element. The curved internal tubular element is inserted inside the curved external tubular element after heating the latter by a heating unit. To form the curved external tubular element on the exact geometry of the curved internal tubular element, a molding unit and a cooling unit are used to obtain a curved tubular segment without spaces between the curved external tubular element and the curved internal tubular element.

Abstract: Method and apparatus for producing a curved tubular segment comprising obtaining a curved external tubular element and a curved internal tubular element made of a material having a resistance to wear greater than that of the curved external tubular element and having a cross section such as to cover at least part of the internal surface of the curved external tubular element. It provides the insertion of the curved internal tubular element inside the curved external tubular element after heating the latter by means of a heating unit. Moreover, to form the curved external tubular element on the exact geometry of the curved internal tubular element a molding unit and a cooling unit are used to obtain a curved tubular segment without spaces between the curved external tubular element and the curved internal tubular element.

Abstract: A method to make a curved tubular element comprising obtaining a first external curved tubular component, and a second internal curved component made of a material with a greater resistance to wear than the first external curved tubular component, and having a cross section which covers a portion of the internal surface of the first external curved tubular component. The first external curved tubular component includes at least two parts. Each of the parts has a cross section which is a respective portion of the complete tubular section of the first external curved tubular component; to bring the at least two parts near each other along respective connection edges, disposing the second internal curved component internally in contact with at least one of the two parts; to weld the at least two parts to define the first external curved tubular component and to enclose therein the second internal curved component.