Abstract: “CONSTRUCTIVE DISPOSAL APPLIED IN MECHANICAL EXPANSION FIXER FOR METAL STRUCTURES OR THE LIKE”, which comprises a kit of pieces which form the mechanical expansion fixer (1), it has a hexagonal head (2) and a cylindrical body (3) endowed with full thread (4), has flat washer (5) and a jacket (6) in low-carbon steel; also on the head of the jacket (6) has a hexagonal (7) to ensure that the jacket does not rotate during mounting and tightening, which provides a wide contact area option to use the key that holds the fixer (A and B) in this way, it is not necessary to position it in the hole in a specific way, ensuring agility in the application; cone guided (8) is pre-assembled with the assembly being threaded in the thread base of the fixer (1), there is a unique locking system of guides (9), these guides fit into the openings or slots of jacket (10) and prevent the cone to rotate false in the jacket (6), as the head of the hexagon socket (7) when locked with a fixed key or star prevents this condition, this al