Dowel and method for attaching insulating boards

摘要

The method involves drilling a borehole (4) through an insulating material plate (2) in a sub-structure (3), and cutting a circle with a preset radius in the plate by using a cutting edge. A dowel e.g. screwing dowel, and a spreading unit are inserted into the borehole. The spreading unit is driven into a pressure disk and a dowel case, and the pressure disk is simultaneously moved into an insulating material surface defined by the cut circle under compression.