Trepanning is the process of creating a hole or circular opening by removing a core, in this case by machining. Wachs SDSF Small Diameter Split Frames and DynaPrep MDSF Split Frames have been used successfully for trepanning access holes, manholes, stub-ins, and bearing pockets on pipe, flat plates and more.

Unlike ordinary single purpose drills, when trepanning is complete the SDSF and DynaPrep MDSF can serve as the foundation of a complete weld prep machining system capable of cutting, beveling, counterboring and more. Plus, unlike ordinary drills very large diameter openings can be achieved.