| 摘要 |
FIELD: mining. ^ SUBSTANCE: rolling drilling bit includes housing with nipple and vent passages, cutters of semispherical or flattened spherical shape and their support with vertical trunnions; support of each cutter is made in the form of stepped support shaft, with possibility of rotation, one end of which faces the bottom hole and has rectangular cross section and is fixed inside removable solid cutter, and the other end having the shape of cylinder or flattened cone is installed in the housing hole, and is equipped with ringless thrust ball bearing, and in the hole at the housing outlet the stepped shaft is equipped with sealing elements fixed with unsplit detachable cover attached to the bit housing. For drilling conditions of horizontal wells in mine rocks of small and medium thickness the support shaft is made at an angle of 5-15 degrees to bit axis; at that, teeth of peripheral rim of bits have dimensions which are by 1.2-1.3 times more than those of the last rim. ^ EFFECT: increasing service life and operating efficiency of bit; reducing manufacturing costs. ^ 2 cl, 3 dwg |
