Split blade drill bit

Abstract

This disclosure is directed to drilling tools and, more specifically, drilling bits. One such bit includes a bit body comprising a first gauge pad and a second gauge pad. The bit further includes a first blade comprising a leading portion and a trailing portion, wherein the leading portion is disposed on the first gauge pad with a negative helix angle and the trailing portion is disposed on the second gauge pad with a positive helix angle.

1 . A bit for removing material from a formation, the bit comprising:
 a bit body; and   a first split blade disposed on the bit body comprising a leading portion and a trailing portion, wherein the leading portion is forward sweeping having a negative helix angle and the trailing portion is rearward sweeping having a positive helix angle.   
     
     
         2 . The bit of  claim 1 , wherein a difference between the negative helix angle of the leading portion and the positive helix angle of the trailing portion is at least above a threshold value. 
     
     
         3 . The bit of  claim 2 , wherein the threshold value is a helix differential of between approximately 4° and 8°. 
     
     
         4 . The bit of  claim 1 , wherein the bit body comprises a region between the leading portion and the trailing portion. 
     
     
         5 . The bit of  claim 1 , wherein the bit body comprises a region between the leading portion and the trailing portion having a fluid port disposed therein. 
     
     
         6 . The bit of  claim 1 , further comprising a first gauge pad, wherein the first gauge pad is disposed at a first sweep angle on the bit body, and wherein the first sweep angle is approximately 0°. 
     
     
         7 . The bit of  claim 6 , further comprising a second gauge pad wherein the second gauge pad is disposed at a second sweep angle on the bit body different than the first sweep angle. 
     
     
         8 . The bit of  claim 7 , wherein the second sweep angle is approximately 10°. 
     
     
         9 . The bit of  claim 1 , further comprising a plurality of cutting elements disposed on each of the trailing portion and the leading portion of the first split blade. 
     
     
         10 . The bit of  claim 1 , comprising a second split blade, the second split blade comprising a second leading portion and a second trailing portion, wherein the second leading portion has a second negative helix angle and the second trailing portion has a second positive helix angle. 
     
     
         11 . A bit for removing material from a formation, the bit comprising:
 a bit body comprising a first gauge pad and a second gauge pad; and   a first blade comprising a first leading portion and a first trailing portion, wherein the first leading portion is disposed on the first gauge pad and the first trailing portion is disposed on the second gauge pad wherein the first leading portion has a negative helix angle and the first trailing portion has a positive helix angle such that there is a first helix angle differential of at least a first threshold value between the first leading portion and the first trailing portion.   
     
     
         12 . The bit of  claim 11 , wherein the at least a first threshold value comprises an angle of between approximately 4° and 8°. 
     
     
         13 . The bit of  claim 12 , wherein the bit body further comprises a third gauge pad, wherein the bit further comprises a second blade disposed on the third gauge pad. 
     
     
         14 . The bit of  claim 13 , wherein the second blade comprises a second leading portion and a second trailing portion, wherein the second leading portion is disposed on the third gauge pad and the second trailing portion is disposed on a fourth gauge pad. 
     
     
         15 . The bit of  claim 14 , further comprising a second helix angle differential of at least a second threshold value between the second leading portion and the second trailing portion. 
     
     
         16 . The bit of  claim 15 , wherein the at least a second threshold value is different than the first threshold value. 
     
     
         17 . A bit for removing material from a formation, the bit comprising:
 a bit body comprising a first gauge pad and a second gauge pad; and   a first blade comprising a first leading portion and a first trailing portion, wherein the first leading portion is disposed on the first gauge pad with a forward sweeping orientation in a first direction towards rotation of the bit when the bit is in operation and the first trailing portion is disposed on the second gauge pad with a rearward sweeping orientation in a second direction away from the rotation of the bit when the bit is in operation.   
     
     
         18 . The bit of  claim 17 , further comprising a helix angle differential of at least a first threshold value between the first leading portion and the first trailing portion. 
     
     
         19 . The bit of  claim 17 , wherein the bit body further comprises a third gauge pad and a fourth gauge pad, wherein the bit further comprises a second blade comprising a second leading portion and a second trailing portion, wherein the second leading portion is disposed on the third gauge pad and the second trailing portion is disposed on the fourth gauge pad. 
     
     
         20 . The bit of  claim 19 , wherein the second leading portion has a negative helix angle and the second leading portion has a positive helix angle, and wherein the second leading portion and the second trailing portion comprise a second helix angle differential of a threshold value that is different from the at least first threshold value.