Chip space design for milling with indexable inserts (Flow - WSP)

 

Starting Situation

The efficiency of the manufacturing processes of large gears is often not determined by the wear behaviour of the indexable inserts, but by the removal of chips from the cutting area. Depending on the chip geometry and the chip flow direction, the chips are formed in the flute. The forming processes lead to additional mechanical and thermal stress on the tool. Furthermore, the contact of the chips with the finished component surface can lead to surface defects which influence the component quality.

The removal of the chip material from the machining area is ensured by the size and shape of the chip grooves of the tools and the parameters of the process. There is a conflict of objectives in tool design in that an increase in the number of cutting edges nominally leads to a higher performance of the tools. However, an increase in the number of cutting edges is accompanied by a reduction in the possible size of the chip space.

Research Objective

The aim of the project is to develop a method for chip space design for gear hobbing with WSP tools based on a model for chip flow and chip deformation. The procedure in this project is divided into five work packages. The work packages comprise a theoretical process analysis in which common models for determining chip flow directions are applied to the calculation results of the SPARTAPRO program. Subsequently, the chip flow is investigated in a model process with different chip cross-sections with and without restrictions of the chip space and empirical models are derived for the chip flow direction as well as for the deformation of the chip. The models are validated in different gear cutting processes.