Cooled mandrel for winding a strip product

A cooled mandrel for winding a band product into a coil, comprising a central shaft extending between a rear end connected to rotational driving means round an axis and a front end, a set of adjacent segments mounted to slide radially on said shaft and having curved external faces which connect to form a substantially cylindrical winding surface centered on the axis of the central shaft, means for controlling a variation in diameter of the winding surface, by radial sliding of said segments between an expanded position and a retracted position, and means for cooling the surface of each segment by circulating a heat exchanging fluid comprising, for each segment, a cooling circuit arranged inside said segment and having an inlet orifice and an outlet orifice of the heat exchanging fluid connected each, by means of a fitting of variable length, to a fluid supply or exhaust duct, respectively,

• wherein each fluid supply or exhaust duct, respectively is arranged, at least partially, inside the central shaft and fitted, close to the front end thereof, with a bent portion extending transversally to the longitudinal axis and emerging on a lateral face of said shaft via a supply or exhaust transversal orifice, respectively, which is connected sealingly, by at least one fitting of variable length, to at least one inlet or outlet orifice, respectively, of at least one segment.