Process and system for drilling and lining a bore hole
An apparatus is provided for the drilling of a borehole and its simultaneous lining with cement or the like by the same apparatus. The apparatus comprises a combination spray head and reamer head, a means to drive the reamer head through a borehole and a means for delivering cement to the spray head. Cement is fed to a rotatable spray disc or arms of the spray head, which is arranged to distribute the cement substantially evenly over the internal surface of the borehole created by the reamer head. The apparatus uses lined drill rods, as well as a lined reamer core with a double walled plastic tube. An air transfer assembly is used to connect an internal air source to an air passage contained in the plastic tube, such that the external air source remains stationary during rotation of the lined drill rods and attached reamer and spray heads.
1. A raise bore drilling and lining apparatus for creation of a borehole comprising:
a raise boring drill for boring a raise into a pilot hole using a drill string to create a bore hole; a reamer head affixed to one end of said drill string; a spreader assembly affixed to said reamer head for distributing a liner material on the wall of said bore hole during operation of said reamer head, said spreader assembly comprising a plate rotatable relative to said reamer head; and a material supply connected to said spreader assembly to supply said liner material thereto.
2. Apparatus according to claim 1 wherein said material supply includes a duct extending axially along said drill string.
3. Apparatus according to claim 1 wherein said plate is rotatable by a motor located within said spreader assembly.
4. Apparatus according to claim 3 wherein said motor is driven by fluid supplied through said drill string.
5. Apparatus according to claim 2 wherein said liner material is supplied by a pair of ducts, each carrying a respective component of said liner material.
6. Apparatus according to claim 5 wherein each of said ducts is connected to a respective reservoir within said spreader assembly.
7. Apparatus according to claim 6 wherein said reservoirs are connected to respective pipes to deliver material within said reservoir to said plate.
8. The apparatus of claim 1 wherein said drill string includes a plurality of drill rods connected in seriatim, and wherein each of said plurality of drill rods includes an outer casing and a liner located within said casing, said liner having a plurality of concentric walls defining a series of fluid passageways between successive ones of said walls to convey fluid axially within said rod between opposite ends.
9. A method of drilling and lining a raise bore hole comprising the steps of:
(a) boring a pilot hole with a pilot bit secured to a drill string;
(b) replacing said pilot bit with a reamer assembly including a spreader assembly to distribute lining material;
(c) reaming said pilot hole for a specified distance to create a bore hole by moving said reamer assembly axially in a first direction whilst rotating said drill string;
(d) moving said reamer assembly in an opposite axial direction to said first direction; and
(e) applying a liner material to the wall of said bore hole using said spreader assembly whilst moving said reamer assembly axially in said first direction.
10. The method of claim 9 including repeating steps (c), (d), and (e) until the desired length of bore hole has been created.
11. The method of claim 10 including the step of supplying said liner material through a duct within said drill string.
12. The method of claim 11 including the step of flushing said duct between repetitions of steps (c), (d), and (e).
13. A raise bore drilling and lining apparatus for creation of a borehole comprising:
a raise boring drill for boring a raise into a pilot hole using a drill string to create a bore hole; a reamer head affixed to one end of said drill string; a spreader assembly affixed to said reamer head for distributing a liner material on the wall of said bore hole during operation of said reamer head, said spreader assembly independently rotatable of said reamer head; and a material supply connected to said spreader assembly to supply said liner material thereto.