Production of a double-walled pipe from a single-walled tubular piece comprises applying one end of the tubular piece to a shaping surface of a tool die, moving the end of the piece relative to the shaping surface and further processing

摘要

Production of a double-walled pipe from a single-walled tubular piece (50) comprises applying the first end of the tubular piece to a shaping surface of a tool die (100), moving the first end (60) of the tubular piece relative to the shaping surface of the die to form a transition up to the first end of the pipe touching the inner surface (52) or the outer surface (54) of the first wall and continuing the movement of the single-walled tubular piece relative to the shaping surface of the die to form a second wall whilst the first end moves along a first section of the inner surface or the outer surface of the first wall. An independent claim is also included for a double-walled pipe produced using the above process.