Roughing integrally bladed rotors using cup mill cutters: Method, cutter and program development

Integrally Bladed Rotors (IBRs) are critical parts of gas turbine engines and manufacturing them is an important issue for delivering high quality products. The current machining methods of producing the airfoil blades of IBRs are point milling and flank milling, which are both time consuming.;For productivity reasons, a new cutting tool---the cup mill cutter and a new method of roughing the airfoil blades of integrally bladed rotors using cup mill cutters are proposed. According to this method, the convex suction side and the concave pressure side of the airfoil blades are formed respectively with the inner circumferential surface and the outer circumferential side of the cutting tool, controlling in the same time the bottom side of the cutting tool with respect to the gas path surface.;The developed program is based on the method and it automatically generates the tool path for roughing the airfoil blades of a certain part from the integrally bladed rotor family manufactured at Pratt & Whitney Canada (P&WC). The cutting tool is the cup mill cutter designed and produced at P&WC. The Interactive User Access (IUA) program uses as the input the cup mill cutter geometry and dimensions and specifically selected elements from the CATIA RTM 3D model of the IBR part. The output is the tool path as a 3D representation in CATIA. The tool path is then used in the NC mill module of CATIA to create the NC mill program, which is transferred to VERICUT RTM for digital simulation and validation.;A cutting conditions control method is also proposed for roughing the airfoil blades of the integrally bladed rotor part using the cup mill cutter.;The project deals with the development of a new technology of manufacturing integrally bladed rotors. This new technology comprises the development of new cutting tools, a new method of roughing IBRs, tool path generation program, and cutting conditions control method.;The analytical results have been validated by a manufacturing test. The machining test has been performed on a 5-axis machine and on an aluminum test piece using the already created NC mill program.;The proposed new technology proves to be more productive than the current technology of roughing the airfoil blades of integrally bladed rotors. Moreover, it can be implemented for mass production right away and without additional costs.;The increased productivity, tool cost reduction and a more stable milling process, which eliminates additional rework operations, can impose this technology as the roughing manufacturing technology of integrally bladed rotors.