DIAMOND TURBODRILL Russian patent published in 1997 - IPC

FIELD: equipment for drilling wellbores of oil and gas wells, more specifically, technical means of turbodrilling in which turbodrills are provided with diamond drill bits which are connected to their shafts with the help of thread. SUBSTANCE: diamond turbodrill has turbodrill and axisymmetric diamond drill bit whose overall transverse size is smaller by 2-5 mm than inside diameter of casing through which drill bit is lowered into wellbore. In this case, the smallest distance form turbodrill longitudinal axis and corresponding axis of drill bit connection thread, with the help of which it is secured to lower end of turbodrill shaft, up to drill bit outside side surface equals half of overall diameter of turbodrill body. Diamond cutters on drill bit rock cutting surface are arranged so that their location density is maximum on the side of minimum distance from axis of drill bit thread to its side surface and considerably reduces as its distance increases. EFFECT: higher efficiency. 2 cl, 2 dwg