| 摘要 |
A mining drill bit for attachment to a hollow drill steel is provided with water openings in the head thereof on either side of a planar cutting member in close proximity to the leading edges thereof. Preferably the water openings are in addition radially and axially proximate to the chisel edge of the cutting member. Water injected into the end of a bore hole through the water openings efficiently removes drillings from the vicinity of the cutting member. Two planar slurry surfaces formed on diametrically opposite sides of drill bit head and truncating the circumference of the head at the base thereof so as to form chordal lips funnel water injected into the end of the bore hole and cuttings removed from the vicinity of the cutting member away from the end of the bore hole for removal therefrom in two localized columns of high velocity flow that scour accumulations of cuttings from the walls of the bore hole. The cutting member is supported across the full diameter of the drill bit head by triangular support shoulders which are thicker at the trailing edge of the cutting member than at the leading edge thereof.
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