A suction or blow thermal roller includes: a cylindrical body extending along a longitudinal direction; the cylindrical body including at least one inner tubular element and at least one outer tubular element that is concentrically arranged around the inner tubular element; the inner tubular element includes an outer diameter d and the outer tubular element includes an inner diameter D, being D>d; two hubs, each arranged at one end of the cylindrical body; at least one heat-exchange chamber realized between the inner tubular element and the outer tubular element. The roller includes a coating layer for the inner tubular element. The coating layer includes at least one rib arranged along a helical path around the longitudinal direction. The at least one rib is made in one piece in the coating layer, realizing at least one helical channel between the coating layer and the outer tubular element.