For the company Bosch, WMS Noebauer successfully implemented their desire to increase the productivity of their Helitronic Power Production machine. This machine was specifically upgraded to fulfil its primary application for grinding special step drills. This was also a particularly interesting project for WMS Noebauer.

Firstly, the drives were upgraded in order to increase the speed of the machine. Also by renewing the guides, the maximum load ratings and moments were additionally increased. Through the installation of a cooled grinding spindle motor the thermal growth within the machine was eliminated and simultaneously enabled more power to be transmitted to the grinding spindle. At the customer’s request a new control system, together with optimized software, was also installed.

The newly installed recirculating roller guidance systems increased the dynamic load rating of the machine from 62.3 kN to 67.4 kN and the static load rating from 96.6 kN to 175 kN. The permissible static moments were also increased from Ma / MA 1.38 kNm to 1.80 kNm and Mc from 1.53 kNm to 2.81 kNm. This resulted in the machine behaving in a much stiffer manner than before the conversion.

Later in the project, the measurement systems were upgraded utilizing the latest Heidenhain measuring technology. This led, together with the new oil-cooled 30 kW main spindle motor, to a thermal stabilization of the machine, which in turn lead to a significant improvement in the grinding accuracy.


The modifications and additional enhancements performed by WMS Noebauer resulted in reducing the grinding time for a step drill from 8 min 20 sec to 3 min 50 sec.

This represents a grinding time reduction of some 57%, while simultaneously increasing the grinding quality. The life of the tools has also increased significantly.

Although we are used to producing efficiency improvements for our customers, such a significant increase in efficiency is not necessarily an everyday experience and positively surprised not only the company Bosch.

© Copyright 2023 Manfred Nöbauer | Impressum | AGB | Datenschützerklärung