A novel general mathematical model for machining globoid screw rotor surfaces using a disk-type cutting tool

Workpieces with a globoid shape have been used extensively in industry. However, its hourglass shape increases machining difficulty and requires exact accuracy during manufacturing. The issues could be remedied using a different manufacturing procedure to minimize machining difficulties. As a result, our research developed a way to reduce machining challenges. The novelty of the study is the general mathematical model for machining the globoid screw rotor surface. The machining process on both flank surfaces of the workpiece is conducted simultaneously using a disk-type cutting tool. Analytical and virtual cutting simulations on globoid screw rotor surface machining are investigated. The machine setting and the coordinate system are proposed. A mathematical model for the surface of the tool and workpiece is presented. The generation of the workpiece surface on the offered machine is investigated. The machining process simulation of the globoid screw rotor surface by the disk-type cutting tool is performed. The numerical solution of cutting points and the normal deviation of the globoid rotor surface are solved. Sensitivity analysis, additional movements, cutting tool assembly error, and the numerical solution for machine-axis settings using the Levenberg–Marquardt algorithm are conducted. Virtual cutting simulation is presented using VERICUT. Verification of mathematical modeling is performed. The hourglass worm and the roller-gear cam are taken as numerical examples. Results from the machining examples are presented to verify the advantages of manufacturing the globoid rotor surfaces in the proposed method.