Abstract The article presents a newly developed method for single-operation extrusion of conical radiators. This is the author’s radiator manufacturing method being the subject of a patent application. The proposed method enables the manufacture of radiators either with or without an inner opening and with an integral plate. Selected results of numerical computations made within Forge®3D, a finite element method (FEM)-based software program, were presented during the analysis of the process. A comparative analysis of the proposed manufacturing method using the double-sided extrusion method was also made. The proposed manufacturing method is assumed to produce radiators in a single technological operation with the stock material being standardized 30 mm-diameter aluminium bars. The objective of the developed method is also to reduce the energy-force parameters.