The Carl-Eduard-Schulte Foundation

"Analysis of process forces and dynamics in BTA deep drilling and qualification of micromagnetic testing systems for in-process characterisation of surface integrity"

Boring and Trepaning Association (BTA) deep drilling is used as a machining process for producing bores with large diameters and a length-to-diameter ratio greater than ten.
Due to the characteristic chip removal process, in which the chips do not come into contact with the bore wall, this method enables a high bore quality to be achieved; Among other things, this process is used in the machining of hydraulic cylinders, landing gear components in the aerospace industry, and components for the chemical industry.
As part of his Master’s thesis, Mr Brause investigated the influence of process control variables on the forces, moments and dynamic properties occurring during the process, as well as on the surface finish of the deep bores. In addition, a non-destructive evaluation of the surface layer is carried out using what is known as magnetic Barkhausen noise, which provides information regarding the planned use of sensor technology in the control loop of the deep-hole drilling process.
This comprehensive thesis describes, in a logical and structured sequence, the motivation behind the investigations, the current state of the art, the experimental conditions of the investigations, and the evaluation and analysis. In industrial practice, the results of this thesis can be used to improve process reliability. Furthermore, it is demonstrated that a testing system for measuring micromagnetic parameters can be applied in a rotating borehole.

This thesis was carried out at the Institute of Machining Technology within the Faculty of Mechanical Engineering at TU Dortmund University. It was supervised by Prof. Dr.-Ing. Prof. h.c. Dirk Biermann of the Institute of Machining Technology within the Faculty of Mechanical Engineering at TU Dortmund University.