Grinding tools are not in a usable condition as delivered or after a longer period of use. Grinding wheels exhibit macrogeometrical faults (e. g. roundness deviation, waviness, macro-wear, loss of profile), which lead to problems in the grinding process or to deficient dimensional accuracy of the components worked upon. Micro-wear, i. e. dulling of the grits, is associated with an increase in the grinding forces as well as the required grinding power. Moreover, the danger of heat- related damage on the surface layers of the workpiece also increases (Fig. 6-1).
blunting of the grams cutting edges raise of grinding forces
damage of the external zone
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of the workpiece
Fig. 6-1. Motivations for grinding wheel preparation
The goal of preparation for use is to create a grinding wheel condition which corresponds to the requirements of the grinding process. This is, on the one hand,
necessary for the first use of a grinding tool. On the other hand, consistent workpiece quality can only be maintained by repeated tool preparation during the process as well. The grinding tool preparation that satisfies the requirements has a decisive influence on the performance of the grinding operation. One essential objective can be the best possible adaptation of the grinding wheel to the machining process in large-batch production. Beyond this, the cutting properties of the tools can also be changed in a targeted manner with respect to varying machining conditions in single and small-batch production.
The concept of conditioning encompasses the various processes used to prepare grinding tools. Fundamentally, we distinguish between the dressing and cleaning of grinding wheels. Dressing is further subdivided into profiling and sharpening. The profiling process gets rid of geometrical errors and gives the workpiece the desired form. Sharpening gives it the required cutting ability. Cleaning the grinding wheel removes the chip, grit and bond residues clogging the pore spaces.