METHOD AND ARRANGEMENT FOR GRINDING BUTTON DRILL BITS, AND AN ABRASIVE WHEEL FOR CARRYING OUT THE METHOD

摘要

The invention concerns a method for grinding button drill bits, in which an abrasive wheel is used to restore the original form of a button in a button drill-bit. The grinding is carried out according to the invention at a temperature in the grinding region of approximately 250-700 °C. The invention concerns also an arrangement for the grinding of button drill-bits in which an abrasive wheel is used to restore the original form of a button in the button drill-bit, which abrasive wheel is provided with upright side flanges and an intermediate groove, where the arrangement comprises an arrangement for directing a stream of a cooling agent onto the side flanges and groove of the abrasive wheel. The invention concerns also an abrasive wheel that comprises diamonds with a mean particle size of 200 µm or greater, embedded in a matrix.