Dividing possible drill bit for perforation tool kit and perforation tool, and perforation tool

摘要

This invention regards the perforation tool kit which possesses the plural perforation tools which possess individual effective drill diameter in 1st feature. The individual drill of this set, the basis itself and two bits, namely, has the central bit (3) and the peripheral bit (4). These drill bits are installed in the pocket inside the drill point. In order to take the equilibrium of the drill, radial range difference between individual bit pocket opposite with respect to the basis itself where two which is while drill setting differs, differs from the radial range difference with central axis and the peripheral pocket of main internal of that basis. Furthermore, this invention regards also the dividing possible drill bit for perforation tool of particular type in 2nd feature.