Development of a Holistic Approach for Increasing Bore Quality at High-Speed-Reaming under Special Consideration of Low-Frequency Pendulum- Oscillations

• Applicant: Professor Dr.-Ing. Eberhard Abele
• Subject Area: Metal-Cutting and Abrasive Manufacturing Engineering
• Term: from 2014 to 2018
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 257237303

Aim of the research project is to increase the bore quality at reaming processes with multi cutter tools by reducing low frequency lateral oscillations. Therefor object of investigation are multi blade reamers made of carbide with a diameter of 10 mm and a cantilever length of 4xd.The number of cutting edges as well as the pitch angle will be defined during the progress of the project as a result of the process simulation. State of the art are tools with six cutting edges and a small non symmetric pitching of 3-5° for those area of tool diameters. To figure out the reason of the cause of lateral oscillations a dynamic simulation model (multi-body-model) will be implemented. Besides the stationary process phase the model will also consider the non stationary phase when the cutting edges start penetrating into the material which is relevant for the beginning of the oscillations. In a second step the developed multi-body- model enables to a simple and cost effective variation of relevant geometric parameters of the reaming tool and their impact on the bore quality. The therefore used methods pursue the objective to reduce the load collective on the main cutting edge as well as the extension of the guiding function of the secondary cutting edges. By this measures the penetration of the cutting edges of the surrounding workpiece will be minimized. To deliver also a contribution to the reduction of the manufacturing costs besides the fulfillment of the required circularity tolerances (and cylindricity) the developed tool has to have a higher tool life compared to the extremely uneven segmented reamers. Therefor within the project should be investigated which disturbances and cause-effect relationships lead to low frequency lateral oscillations and which geometric changes of main and secondary cutting edges have to be done to reduce them. Additionally further modifications of the reaming tool have to be identified which are necessary to reliably achieve the required tool life.

• DFG Programme: Research Grants