Earth-boring drill bit with rectangular nozzles

Claim 1

In a bit for drilling earth formations in which the bit includes a metallic shank having a fluid passage, one end of said shank being coated with a hard matrix material bonded to said end and forming a face of said bit, said hard matrix material having a wear resistance greater than that of said metallic shank, a plurality of polycrystalline diamond compact cutters mounted in sockets provided in said matrix and arranged such that the cutters collectively cover substantially the entire area of the bottom of a bore hole in a drilling operation, wherein said cutters include a supporting member and a polycrystalline cutting member so mounted in said matrix that a portion of said support member is beneath said matrix and at least a portion of said polycrystalline cutting member extends beyond the face of said matrix, and wherein said cutters operate to cut by shearing action to produce shavings which must be removed from the region between said face of said matrix and the opposed surface of the formation being cut, the improvement comprising a plurality of nozzles in said matrix face each communicating with said fluid passage for flow of fluid through said nozzles across the face of said matrix, each said nozzle comprising an orifice having a rectangular cross section normal to the axis of said orifice, said rectangular orifices including a height longer than the base thereof and being oriented with the height side extending in a tangential direction to cause the fluid flowing from each nozzle to sweep broadly across the face of the bit, and each of said nozzles being in the face of said bit such that the flow from each nozzle is across the face of said bit and the cutting member of the cutters mounted on said face.