DRILL ASSEMBLY AND METHOD OF USING SAME

Abstract

A drill assembly (10) for use in trenchless subterranean boring, comprising: a drill shoe (20) having a body with a posterior portion (30) and an anterior portion (22), the latter defining a recess while the former comprises drill bits (32) disposed on a front end (34), opposing lateral sides, and flanks to assist the shoe (20) in acting as both pilot bore drilling tool and as reaming tool; a drill head (50) demount ably mounted to tire drill shoe (20) via tire recess and in communication with directional guidance means; a string of connectable drill rods (80), having a bailing end (82) and a leading end (84) when connected, and through which a drilling solution can be pumped towards tire drill shoe (20); a coupling (86) for linking tire leading end (84) to said drill head (50); and a connector (88) for connecting the trailing end (82) to a vehicle. The invention extends to a drill shoe (20) and a method of use and manufacture thereof.

Claims

1. A drill assembly for use in trenchless subterranean boring, the assembly comprising: a drill shoe having a body with a posterior portion and an anterior portion, the latter defining a recess while the former comprises multiple spaced apart drill bits disposed on a front end, opposing lateral sides, and flanks of the posterior portion to assist the shoe in acting as both pilot bore drilling tool and as reaming tool; a drill head demountably mounted to the drill shoe via the recess and in communication with directional guidance means remote from the drill shoe and apt to guide movement of the drill head at a slanted angle, vertically and horizontally into the ground; a string of connectable drill rods, having a trailing end and a leading end when connected, and through which a drilling solution can be pumped towards a solution outlet provided in the drill shoe; a coupling for linking the leading end to said drill head; and a connector for connecting the trailing end to a D-shackle and swivel of a vehicle.

2. The drill assembly of claim 1, wherein the vehicle is a drilling machine.

3. The drill assembly of claim 1, wherein the drill shoe comprises a body being symmetrical about a longitudinal axis.

4. The drill assembly of claim 3, wherein multiple bits are releasably affixed to the posterior portion.

5. The drill assembly of claim 3, wherein multiple bits are integrally formed with the posterior portion and of uniform construction therewith.

6. The drill assembly of claim 4, wherein the bits disposed on the flanks form a linear array of bits that are equidistantly spaced apart.

7. The drill assembly of claim 4, wherein the bits disposed on the sides form a linear arrangement of bits that are equidistantly spaced apart, apart from one bit irregularly disposed relative to the linear arrangement of bits.

8. The drill assembly of claim 7, wherein the one bit is disposed closest to a front portion of the body, between a first and second bit on the respective sides of the body.

9. The drill assembly of claim 1, wherein multiple bits extend away from a front end of the body with respective longitudinal axes of each bit running parallel to a longitudinal axis of the body.

10. The drill assembly of claim 1, wherein the recess comprises multiple spaced apart apertures for locating fasteners.

11. The drill assembly of claim 1, wherein the posterior portion is divided into a generally planar front section and a generally planar rear section, which sections join at a central part of the body having a width and depth greater than the remainder of the body.

12. The drill assembly of claim 11, wherein planes of the rear section and front section form a reflex angle between them of between 190° and 230°.

13. The drill assembly of claim 12, wherein both the rear and front sections comprise flanks that slant away from the respective planes of the rear and front section at an acute angle of between 20° to 80° and which become tapered as they approach respective front and rear ends of the drill shoe.

14. The drill assembly of claim 13, wherein multiple apertures are provided in the rear section for releasably accommodating fasteners for fitting corresponding holes provided in the drill head.

15. The drill assembly of claim 14, wherein the lateral sides are generally planar and disposed directly opposite each other on opposing sides of the longitudinal axis and which extend generally at right angles to the respective generally planar rear and front sections.

16. The drill assembly of claim 15, wherein fringes are provided contiguous with the respective generally planar lateral sides, each fringe terminating against a flush surface of the anterior portion.

17. The drill assembly of claim 16, wherein the fringes are slanted away from the generally planar lateral sides.

18. The drill assembly of claim 16, wherein the flanks, fringes and lateral sides are all angled away from the central part of the body, which central part defines the greatest width and depth, as the flanks, fringes and lateral sides extend towards the respective rear and front ends.

19. The drill assembly of claim 17 wherein the drill shoe body comprises a front end, rear end, two opposing chamfered flanks sloping towards the front end, two opposing chamfered flanks sloping towards the rear end, two opposing beveled fringes sloping towards the front end, two opposing beveled fringes sloping towards the rear end, two opposing lateral sides sloping towards the front end, and two opposing lateral sides sloping towards the rear end.

20. The drill assembly of claim 19, wherein the drill head comprises one or more channels in communication with the drill rod string and through which a drilling solution can be pumped to exit at multiple outlets proximate the recess.

21. (canceled)

22. (canceled)

23. A method for trenchless subterranean boring and reaming, the method comprising the steps of: providing a drill assembly; mounting a drill shoe to a drill head; linking a leading end of a connected string of drill rods, via a coupling, to said drill head; via a connector, connecting a trailing end of said string of drill rods to a D-shackle and swivel of a powering vehicle; actuating rotation of said D-shackle and swivel to rotate the string of drill rods with the drill head and drill shoe; and guiding the drill head by way of directional guidance means, remote from the drill head, to move at a slanted angle, vertically and horizontally into the ground whilst pumping a drilling solution through the drill assembly.

24. A method of manufacturing a drill shoe, comprising the steps of: providing a mass of metal alloy suitable for subterranean drilling; and metal working said mass to form an oblong drill shoe body symmetrical about a longitudinal axis and having a central cross-sectional part with a width and depth greater than front and rear ends thereof and defining multiple linear planes on said body sloping towards said respective front and rear ends as well as a recess for releasably locating a complementary shaped drill head through which a drill solution can be pumped.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The invention is now described by way of example with reference to the accompanying non-limiting diagrammatic drawings. In the drawings:

[0029] FIG. 1 shows an isometric view of a drill assembly for trenchless subterranean boring, in accordance with an embodiment of the invention;

[0030] FIG. 2 shows a top right front isometric view of a drill shoe connected to a drill head of the drilling assembly of FIG. 1;

[0031] FIG. 3 shows a bottom right front isometric view of a drill head of the drill assembly of FIG. 1;

[0032] FIG. 4 shows a left front isometric view of a posterior portion of the drill shoe of FIG. 2, without bits connected thereto

[0033] FIG. 5 shows a left front isometric view of an anterior portion of the drill shoe of FIG. 2, without bits connected thereto;

[0034] FIG. 6 shows a front isometric view of the drill shoe of FIG. 2, without bits connected thereto; and

[0035] FIG. 7 shows a rear isometric view of the drill shoe of FIG. 2, without bits connected thereto.

DETAILED DESCRIPTION OF THE DRAWINGS

[0036] In the Figures, reference numeral 10 refers to a drill assembly for trenchless subterranean boring in accordance with the invention.

[0037] Similarly, reference numeral 20, as best shown in FIG. 2, refers to a drill shoe for use with the drill assembly 10 in subterranean boring in accordance with the invention.

[0038] As depicted in FIGS. 2, 3, 4, and 5, the drill shoe 20 is releasably mountable to a drill head 50 (FIG. 3) by way of bolts (not shown) extending through apertures 52.

[0039] Components of the drill assembly 10 include the drill shoe 20 and drill head 50 together with a directional guidance means (although not shown, typically of the joy-stick type) remotely located in relation to the drill shoe and apt to guide movement of the drill head 50 at either a slanted angle, vertically and/or horizontally into the ground. Further components include a string of drill rods or pipes 80, a suitable connector 88 and coupling 86, and a drilling machine 90 with a rotational power D-shackle and swivel 92, as best shown in FIG. 1.

[0040] The drill head 50 of FIG. 3 is preferably demountably mounted to the drill shoe 20, in communication with directional guidance means for guiding movement of the drill head 50 initially at a slanted angle as it enters the ground, vertically thereafter to reach a suitable drilling depth, and finally horizontally to traverse, for example, a tar or paved road without damaging same there below.

[0041] As shown in the drawings, the string of drill rods 80 has a trailing end 82 and a leading end 84. The connector 88 ensures operative connection between the trailing end 82 and a power take-off shaft connected to the rotational power D-shackle and swivel 92, while the coupling 86 ensures operative linkage between the leading end 84 to the drill head 50.

[0042] The connected pipes 80 are hollow to allow a drilling solution to be pumped therethrough. The pipes 80 are also operatively in fluid communication with the drill head 50.

[0043] The unique shape of the drill shoe body 20, as best shown in FIGS. 2, 4, 5, 6 and 7 of the drawings, wherein the shape thereof is shown to deviate from square, rectangular, and triangular forms by elongation along a longitudinal and crosswise dimension, ensures that the drill assembly 10 can act as both pilot bore drilling tool and as reaming tool all at once.

[0044] Referring to FIGS. 4 and 5, the drill shoe body 20 is symmetrical about a longitudinal axis y-y. The body 20, as best shown in FIG. 5, includes an anterior portion 22 having a generally flush surface 24 in which a recess 26 is defined for releasably locating the drill head 50. The recess 26, as shown, has spaced apart apertures 21 for locating fasteners (not shown) for fastening the drill head 50 to the recess 26.

[0045] The drill shoe body 20 also defines a posterior portion 30 on which multiple bits 32, as best shown in FIG. 2, are releasably affixed. It is envisaged that in other embodiments of this invention, the bits 32 are integrally formed with the drill shoe 20 and of uniform construction therewith. The bits 32 are typically, but not necessarily equidistantly spaced apart on the posterior portion 30. The bits 32 are identically shaped to one another and defines a cylindrical base that tapers towards a pointed tip. The bits 32 are typically manufactured from air-hardened steel metallurgically bonded to tungsten carbide particles. This increases drill shoe durability during use in hard rock conditions.

[0046] As visible from FIG. 4, the posterior portion 30 is divided into a generally planar front section 34 and a generally planar rear section 36, which sections meet at a central part 36 of the body 20, which central part has the greatest width and depth compared to the rest of the body 20. This central part 36 appears as a broadened waist on the body 20. Planes of the rear section and front section 36,34 form a reflex angle between them of between 190° and 230°.

[0047] Both the rear and front sections 36,34 further define flanks 38.1; 38.2 that slant away from the respective planes of the rear and front section 36,34 at an acute angle of between 20° to 80° and which become tapered as they approach respective front and rear ends of the drill shoe body 20.

[0048] Multiple apertures 21 is provided in the rear section 36 for releasably accommodating fasteners such as bolts for fitting corresponding holes 52 provided in the drill head 50.

[0049] Still referring to FIG. 4, a pair of generally planar lateral sides 40.1; and a second pair of generally planar lateral sides 40.2 are formed on the shoe body 20. Each pair 40.1;40.2 is disposed directly opposite each other on lateral sides of the longitudinal axis Y-Y. The sides 40 extend generally at right angles to planes of the respective rear and front sections 36,34.

[0050] Two pairs of fringes 42.1;42.2, contiguous with the respective generally planar sides 40.1;40.2, terminate against a flush surface 24 of the anterior portion 22. The fringes 42 are formed to slant away from the generally planar lateral sides 40 in a direction towards the longitudinal axis Y-Y.

[0051] As shown in the drawings, two opposing pairs of flanks 38.1; 38.2, two opposing pairs fringes 42.1; 42.2 and two opposing pairs lateral sides 40.1;40.2 are shaped on the body 20. The flanks 38, fringes 42 and sides 40 are all angled away from the central part or broadened waist 36 of the body 20 as they extend towards the respective rear and front ends 44,46, as best shown in FIGS. 4 and 5.

[0052] Referring to FIG. 3, the drill head 50 consists of two channels 54 in communication with the drill pipe string 80 and through which a drilling solution can be pumped so as to exit at one or more outlets proximate the recess 26.

[0053] In use, the drill assembly 10 as described herein, with its respective components are acquired. Thereafter, by utilisation of suitable bolts extendable through apertures 21 and 52, the drill head 50 is fastened to fit the recess 26 of the drill shoe body 20. The fasteners are preferably suitably torqued with complementary nuts (not shown).

[0054] Next, a leading end 84 of a string of drill rods 80, is coupled via a coupling 86 to the drill head 50 at its rear side. Then, a trailing end 82 of the string of drill rods 80 is connected via a connector 88 to a rotational power take-off shaft 92 of the vehicle 90. Actuation of rotation of the power take-off shaft 92 follows, which in turn permits the string of drill rods 80 to rotate with the drill head 50 and drill shoe 20 attached thereto.

[0055] Finally, the drill head 50 is guided by way of directional guidance means (not shown), remote from the drill head, to move at a slanted angle, vertically and eventually horizontally into the ground whilst pumping a drilling solution through the shoe 20.

[0056] While preferred embodiments of the invention are shown and described, it will be understood that it is not intended to limit the extent of the invention, but rather it is intended to cover all modifications and alternate methods, including: methods, for using the drill assembly 10 falling within the spirit and the scope of the invention.

[0057] The applicant believes that the drill assembly 10 of the present invention, at least in part, addresses shortcomings in conventional trenchless drilling units in that it provides a neat, sturdy, functional and cost-effective alternative which has fewer components and are easier to manufacture compared to ubiquitous drilling units and allows for reaming and drilling at the same time.

[0058] The invention for which patent protection is sought is defined in the set of claims that follows.