A cooling chamber having a cylindrical shape with an axis defined between two end walls (162, 164) and a circumferential axial wall, and comprising a cooling fluid entry port and a cooling fluid exit port connectable to respective source and drain of a cooling fluid; a heat exchanger within walls of the cooling chamber for circulating the cooling fluid between the source and the drain of the cooling fluid, and comprising an entry manifold element defined as a cavity within one of the end walls, being associated and in fluid communication with said entry port, and an exit manifold element, defined as a cavity within said one of the end walls, being associated and in fluid communication with said exit port, the entry manifold element and the exit manifold element being in fluid communication with at least two conduit systems defining corresponding at least two cooling fluid flow paths between the entry and exit manifolds, said conduit systems being constituted by consecutive conduit segments, the conduit segments being bores or cavities formed within the walls of the cooling chamber, each of the at least two conduit systems comprises a plurality of first axial segments spanning the distance between said two end walls and a plurality of second peripheral segments formed in the end walls, each of said peripheral segments linking two axial segments that are consecutive in said flow path. a cooling fluid entry port and a cooling fluid exit port connectable to respective source and drain of a cooling fluid; a heat exchanger within walls of the cooling chamber for circulating the cooling fluid between the source and the drain of the cooling fluid, and comprising an entry manifold element defined as a cavity within one of the end walls, being associated and in fluid communication with said entry port, and an exit manifold element, defined as a cavity within said one of the end walls, being associated and in fluid communication with said exit port, the entry manifold element and the exit manifold element being in fluid communication with at least two conduit systems defining corresponding at least two cooling fluid flow paths between the entry and exit manifolds, said conduit systems being constituted by consecutive conduit segments, the conduit segments being bores or cavities formed within the walls of the cooling chamber, each of the at least two conduit systems comprises a plurality of first axial segments spanning the distance between said two end walls and a plurality of second peripheral segments formed in the end walls, each of said peripheral segments linking two axial segments that are consecutive in said flow path. an entry manifold element defined as a cavity within one of the end walls, being associated and in fluid communication with said entry port, and an exit manifold element, defined as a cavity within said one of the end walls, being associated and in fluid communication with said exit port, the entry manifold element and the exit manifold element being in fluid communication with at least two conduit systems defining corresponding at least two cooling fluid flow paths between the entry and exit manifolds, said conduit systems being constituted by consecutive conduit segments, the conduit segments being bores or cavities formed within the walls of the cooling chamber, each of the at least two conduit systems comprises a plurality of first axial segments spanning the distance between said two end walls and a plurality of second peripheral segments formed in the end walls, each of said peripheral segments linking two axial segments that are consecutive in said flow path.