Investigation of cooling systems in a glass grinding process


Edge grinding is an important process step in the manufacturing of glass for automobile and display industry. Short cycle times demand high material removal rates of the grinding wheel. Coolant needs to be supplied to achieve a timewise efficient grinding process without melting the glass.

Different cooling systems are tested against a standard coolant system in a series of experiments. Their performance in terms of edge surface roughness and grinding wheel wear is being compared.

Intensive studies for all cooling systems involving laser profiling and 3D microscopy for wear analysis are performed. Attritious wheel wear is detected indirectly due to grinding current increase.

Furthermore, it is found that a single nozzle directed towards the contact zone is sufficient to cool the process, which reduces the amount of coolant necessary by a factor of up to 10.

A force model is tested, which is implemented in a kinematic geometric grinding simulation tool. The force model is the base for further models for temperature and wear, which can be implemented as well.



Investigation of Breaking Stresses on Cut-Edge Quality


Cutting and breaking is a common step in the production process of float glasses. On a machine manufactured by Glaston, the process is controlled by a breaking sphere, pressing on the upper surface and a “satellite” supporting from the lower surface.

Investigations of different positions of the sphere and the satellite and their effect on stress distribution are studied. Both, experimental observations and computational FEM simulations are compared.

These stresses are responsible for how the glass is breaking. A holistic understanding of those stresses will allow to achieve an optimal cut-edge. Principles can be derived from investigations on different shapes to improve the quality of manufactured parts.