Drilling apparatus, method, and system

Abstract

A helical drag bit provided with spirally/helically positioned cutting arms. The arms can create a spiral trench geometry in the sidewall of a predrilled pilot hole. The cutting arms can terminate in scoring cutting blades. The helical drag bit can be incorporated into a system and method for measuring geo-tech characteristics. The helical drag bit can be used in a system and method for improving the holding capacity of rock bolts and similar devices for use in the mining industry or in any circumstances where a particulate substrate may benefit from support. Novel rock bolts having new structures can be used with this improved hole geometry or may form such improved hole geometry.

1 . A helical drag bit, comprising: 
 a bit shaft having a tip-end; and    a plurality of cutting arms on said bit shaft, each of said cutting arms having an axial length and being positioned around said bit shaft with a consistently angled pitch;    wherein said axial length of each said cutting arm is greater relative to cutting arms positioned closer to said tip-end of said bit shaft such that said plurality of cutting arms are configured to cut a spiral groove into an interior surface of a pilot hole.    
   
   
       2 . The helical drag bit of  claim 1 , wherein said bit shaft is segmented into stackable flights, each of said flights comprising at least two said cutting arms.  
   
   
       3 . The helical drag bit of  claim 1 , wherein each of said cutting arms terminates in a scoring blade.  
   
   
       4 . The helical drag bit of  claim 3 , wherein said scoring blades are configured to cut a kerf in rock through which said helical drag bit is drilling.  
   
   
       5 . The helical drag bit of  claim 1 , wherein said helical drag bit is part of a detached, self-driven, underground autonomous tethered drill system.  
   
   
       6 . The system of  claim 5 , further comprising a computer in communication with said helical drag bit, wherein said system is configured to measure geo-technical characteristics of a substrate through which said helical drag bit is drilling.  
   
   
       7 . The helical drag bit of  claim 1 , wherein said helical drag bit is in communication with a computer and configured therewith to measure geo-technical characteristics of a substrate through which said helical drag bit is drilling.  
   
   
       8 . A system for reinforcing a substrate, comprising: 
 a helical drag bit having a substantially cylindrical bit shaft and a plurality of cutting arms on said bit shaft, each of said cutting arms having an axial length and being positioned around said bit shaft with a consistently angled pitch, wherein said axial length of each said cutting arm is greater relative to cutting arms positioned closer to a tip-end of said bit shaft such that said plurality of cutting arms are configured to cut an optimal hole geometry into an interior surface of a pilot hole;    a reinforcing bolt structure configured for insertion into said pilot hole; and    an anchoring means configured to hold said reinforcing bolt structure within said pilot hole by interacting with said optimal hole geometry.    
   
   
       9 . The system of  claim 8 , wherein said optimal hole geometry comprises a spiral groove in the interior surface of said pilot hole.  
   
   
       10 . The system of  claim 8 , wherein said anchoring means is grout.  
   
   
       11 . The system of  claim 8 , wherein said anchoring means is a mechanical anchor comprising axially extending regions corresponding to said optimal hole geometry.  
   
   
       12 . The system of  claim 8 , wherein said reinforcing bolt structure comprises axially extending regions corresponding to said optimal hole geometry.  
   
   
       13 . The system of  claim 8 , wherein said helical drag bit and said reinforcing bolt structure are part of the same structure.  
   
   
       14 . A method of cutting a spiral groove into the interior surface of a pilot hole, comprising: 
 inserting a helical drag bit into a pilot hole, said helical drag bit having a substantially cylindrical bit shaft corresponding in size to said pilot hole and a plurality of cutting arms on said bit shaft, each of said cutting arms having an axial length and being positioned around said bit shaft with a consistently angled pitch, wherein said axial length of each said cutting arm is greater relative to cutting arms positioned closer to a tip-end of said bit shaft; and    rotating said helical drag bit in a direction corresponding to said consistently angled pitch.    
   
   
       15 . The method of  claim 14 , wherein said bit shaft is segmented into stackable flights, each of said flights comprising at least two said cutting arms.  
   
   
       16 . The method of  claim 15 , wherein only one flight of said helical drag bit is advanced into said pilot hole at a time.  
   
   
       17 . A method of enlarging a pilot hole, comprising: 
 inserting a helical drag bit into said pilot hole, said helical drag bit having a substantially cylindrical bit shaft corresponding in size to said pilot hole and a plurality of cutting arms on said bit shaft, each of said cutting arms having an axial length and being positioned around said bit shaft with a consistently angled pitch, wherein said axial length of each said cutting arm is greater relative to cutting arms positioned closer to a tip-end of said bit shaft and each said cutting arm terminates in a scoring blade; and    rotating said helical drag bit in a direction corresponding to said consistently angled pitch.    
   
   
       18 . The method of  claim 17 , wherein said wherein said bit shaft is segmented into stackable flights, each of said flights comprising at least two said cutting arms.  
   
   
       19 . The method of  claim 18 , wherein only one flight of said helical drag bit is advanced into said pilot hole at a time.  
   
   
       20 . The method of  claim 17 , wherein said scoring blades of said cutting arms cut a kerf into a substrate through which said helical drag bit is rotating.  
   
   
       21 . A system for supporting a substrate with a rock bolt, comprising: 
 a rock bolt, said rock bolt being configured for insertion into a rock bolt hole; and    at least one protuberance on said rock bolt, said at least one protuberance being configured such that it will form a groove in a wall of said rock bolt hole when said rock bolt is inserted into said rock bolt hole, wherein said rock bolt is thereby supported in said rock bolt hole at least in part by said at least one protuberance and said groove.    
   
   
       22 . The system of  claim 21 , wherein said groove is at least partially formed by a rotation of said rock bolt.  
   
   
       23 . The system of  claim 21 , wherein at least a portion of said groove is semi-annularly shaped.  
   
   
       24 . The system of  claim 21 , wherein at least a portion of said groove is spirally shaped.  
   
   
       25 . The system of  claim 21 , wherein a plurality of said protuberances are provided on said rock bolt.  
   
   
       26 . The system of  claim 25 , wherein said plurality of protuberances are all the same size.  
   
   
       27 . The system of  claim 25 , wherein each protuberance of said plurality of protuberances has an increased radial length relative to any protuberance closer to a tip end of said rock bolt.  
   
   
       28 . The system of  claim 21 , wherein said at least one protuberance is rounded.  
   
   
       29 . The system of  claim 21 , wherein said at least one protuberance is angular.  
   
   
       30 . The system of  claim 21 , further comprising an adhesive.  
   
   
       31 . The system of  claim 30 , wherein said adhesive is grout.