Nozzle placement in a diamond rotating bit including a pilot bit

Claim 1

An improvement in a rotating bit including a main bit body and a pilot bit extending therefrom characterized by a longitudinal axis, said improvement comprising: a plurality of cutting elements disposed on said bit, wherein said main bit body includes a main gage and a plurality of reamer lobes extending from said main gage to said pilot bit, said plurality of elements being disposed on said pilot bit and on said plurality of reamer lobes; at least one nozzle defined in said pilot bit; and at least one nozzle defined in each of said reamer lobes, said reamer and pilot nozzles for providing drilling fluid across said pilot bit and reamer lobes respectively, said plurality of reamer lobes being defined by junk slots between adjacent reamer lobes, and wherein said reamer nozzle is particularly characterized by disposition on said reamer lobe so that fluid exiting said reamer nozzle is distributed across said reamer lobe to said adjacent junk slots and gage, said reamer nozzle disposed at an upward acute angle with respect to said longitudinal axis, wherein said pilot bit includes a pilot gage and wherein said plurality of reamer lobes extend from said main gage of said main bit body to said pilot gage, said pilot gage including a plurality of pilot junk slots defined therein, and wherein said reamer nozzle is disposed on said reamer lobe in an azimuthally overlapping configuration with said pilot junk slots whereby fluid from said pilot nozzles flows across said pilot bit to said pilot junk slots and is therein entrained with fluid ejected from said reamer nozzles and flows in an accelerated manner across said main bit body.

Claim 6

A method for improving flow of a drilling fluid across a rotating bit having a a pilot bit and reamer comprising the steps of: providing drilling fluid to said face of said pilot bit, said drilling fluid flowing across said face of said pilot bit in a generally radial direction to establish a first flow pattern of said drilling fluid on said pilot bit, said first fluid flow pattern is established across a pilot bit and in particular along junk slots defined in the gage of said pilot bit; and directionally injecting drilling fluid across the flank of a main reamer bit disposed adjacent to said pilot bit at a selected point in relation to said first fluid flow pattern in said junk slots defined in the gage of said pilot bit to increase velocity of said drilling fluid across the face of said pilot bit and to establish a second fluid flow pattern across said reamer, whereby cooling and cleaning efficiencies can be improved and whereby said second fluid flow pattern serves in part to suction said drilling fluid across said first fluid flow pattern.

Claim 7

A method for improving flow of a drilling fluid across a rotating bit having a a pilot bit and reamer comprising the steps of: providing drilling fluid to said face of said pilot bit, said drilling fluid flowing across said face of said pilot bit in a generally radial direction to establish a first flow pattern of said drilling fluid on said pilot bit, said first fluid flow pattern is established across a pilot bit and in particular along junk slots defined in the gage of said pilot bit; and directionally injecting drilling fluid across the flank of a main reamer bit disposed adjacent to said pilot bit at a selected point in relation to said first fluid flow pattern in said junk slots defined in the gage of said pilot bit to increase velocity of said drilling fluid across the face of said pilot bit and to establish a second fluid flow pattern across said reamer, whereby cooling and cleaning efficiencies can be improved and whereby said second fluid flow pattern serves in part to suction said drilling fluid across said first fluid flow pattern.