XINFENG SCREWS

Thread cutting screws are tapping screws that have cutting flutes or edges at their point so that when threading cutting screws are driven into a preformed hole, the thread cutting screws act as taps and actually cut its own mating thread.

thread cutting screws to be screwed into a predrilled hole in concrete, masonry, or the like is characterized in that the relationship between the load bearing thread surface AOn of the loaded thread flank, which surface is standardized to the load bearing thread length he and cut into the wall of the predrilled hole, and the nominal diameter db of the predrilled hole is as follows