A heat exchange device for heat exchange between a first fluid, preferably a gas to be cooled, circulating through a first conduit; and a second fluid, preferably a coolant, circulating through a second conduit, where said device is intended for being intercalated between both conduits and comprises: - a sheet metal shell having a tubular configuration, - a first sheet metal baffle and a second sheet metal baffle assembled in the sheet metal shell and spaced from one another, - a bundle of conduits extending along a longitudinal direction X-X' at least from the first baffle to the second baffle, - a bypass conduit extending at least from the first baffle to the second baffle and it is parallel to the bundle of conduits, - a fluid communication inlet and a fluid communication outlet (1.4, 1.5) for the second fluid, both arranged in the sheet metal shell and giving access to the space located between the first baffle and the second baffle for cooling the bundle of conduits, - a first fluid communication inlet/outlet (10.1) arranged at one of the ends of the bundle of conduits and of the bypass conduit, and a second fluid communication inlet/outlet (1.6, 9.1) arranged at the opposite end of the bundle of conduits and of the bypass conduit, both the fluid communication inlet/outlet (10.1, 1.6, 9.1) giving access to the first fluid through the bundle of conduits, through the bypass conduit or through both (2, 5), where the tubular sheet metal shell extends longitudinally beyond the second baffle giving rise to a chamber such that said chamber comprises a valve that can be actuated from outside the chamber and is adapted to at least close the bypass conduit, and where said valve comprises a shaft attached to the sheet metal shell and capable of rotating with respect to said shell, prolonging into the chamber where said shaft comprises a sheet metal flap (6.1) adapted to sit on the perimetral edge of the end of the bypass conduit for closing same, and characterized in that the chamber comprises a stamped sheet metal part dividing the chamber into an inner sub-chamber (Ci) in communication with the inside of the tubes of the bundle of conduits and an outer sub-chamber (Co), and where said stamped sheet metal part comprises a first opening (11.1) and a second opening (11.2) such that: - the stamped sheet metal part establishes a perimetral closure with the shell, - the first opening (11.1) establishes fluid communication between the inner sub-chamber (Ci) and the outer sub-chamber (Co), - the second opening (11.2) perimetrically surrounds the bypass conduit; and - the second fluid communication inlet/outlet (1.6, 9.1) is in direct communication with the outer sub-chamber (Co); and wherein it is possible to completely close the bypass conduit so that the flow goes through the bundle of tubes as well as completely close the passage through the bundle of tubes so that the flow goes through the bypass conduit completely. - a sheet metal shell having a tubular configuration, - a first sheet metal baffle and a second sheet metal baffle assembled in the sheet metal shell and spaced from one another, - a bundle of conduits extending along a longitudinal direction X-X' at least from the first baffle to the second baffle, - a bypass conduit extending at least from the first baffle to the second baffle and it is parallel to the bundle of conduits, - a fluid communication inlet and a fluid communication outlet (1.4, 1.5) for the second fluid, both arranged in the sheet metal shell and giving access to the space located between the first baffle and the second baffle for cooling the bundle of conduits, - a first fluid communication inlet/outlet (10.1) arranged at one of the ends of the bundle of conduits and of the bypass conduit, and a second fluid communication inlet/outlet (1.6, 9.1) arranged at the opposite end of the bundle of conduits and of the bypass conduit, both the fluid communication inlet/outlet (10.1, 1.6, 9.1) giving access to the first fluid through the bundle of conduits, through the bypass conduit or through both (2, 5), - the stamped sheet metal part establishes a perimetral closure with the shell, - the first opening (11.1) establishes fluid communication between the inner sub-chamber (Ci) and the outer sub-chamber (Co), - the second opening (11.2) perimetrically surrounds the bypass conduit; and - the second fluid communication inlet/outlet (1.6, 9.1) is in direct communication with the outer sub-chamber (Co);