Device for welded joints in pipework

A device to be installed in pipes, that eliminates internal corrosion in the welded joints because it prevents the damage of the welding heat to the inner coating of said pipes by dissipating it naturally and spontaneously, comprising a first part (1) which is assembled to a second part (2) producing a confined space (51) where both parts (1 and 2) are formed by two concentric rings, an inner ring (4, 21) of the same diameter as the pipe (38), and an outer ring (3, 20) with the rings joined together by a solid steel mantle (5, 22);

• the inner ring (4) has a cavity (8) where a guide wedge (29) of the inner ring (21) is assembled and at the bottom of the cavity (8) of the first part (1) there is a concavity (9) to accommodate an fluor elastomer ring (45) and at the end of the guide wedge (29) of the second part (2) there is a concavity (30) confining said ring of fluor elastomer (45) to the concavity (9), and the inner area of the contact surfaces (39) between the inner rings (4, 21) are protected with a highly adhesive epoxy seal, a separation of 2 to 3 millimeters (46) is achieved between the outer rings (3, 20) where the welded joint (44) is done, wherein the width (10, 23) of the solid steel mantle (5, 22) that separates the inner and outer rings of the first part and the second part is at least 50 mm and the thickness (14, 24) of this solid steel mantle (5,22) as well as the thickness of the assembly area (52) between the cavity (8) of part (1) and the guide wedge (29) of part (2) is at least twice the thickness of the pipe (40, 41).