| 摘要 |
FIELD: mining.SUBSTANCE: diamond crown bit includes a body and a matrix separated with washing slots into working sectors reinforced with cutting elements in a radial section in the form of a rectangle and rectangular trapezoids, inclined sides of which are directed to opposite sides. All working sectors in the section perpendicular to the radius of the crown are made in the form of a rectangular trapezoid, the inclined face of which is arranged at the incoming side, at the same time working sectors with rectangular cross section are reinforced with inserts from synthetic superhard materials, besides, inserts are arranged in the zone of crossing of the inclined and end surfaces of rectangular sectors with circumference that divides the end of the sector into two parts of equal thickness. The sum of smaller bases of rectangular trapezoids in radial direction may not be more than the width of the matrix end. The inclined incoming face of each sector may be reinforced with diamonds of smaller fraction compared to the horizontal section of the end surface.EFFECT: increased efficiency of crown operation, higher tunnelling and mechanical speed of drilling.3 cl, 6 dwg |
