VIBRATIONAL DRILL HEAD

Abstract

A drill head system including a drill head having a spindle configured to be operatively coupled to a vibration source to cause the spindle to vibrate in an axial direction, the spindle having a passageway. The system further includes a sleeve receiving said spindle therein with a gap therebetween. The sleeve is configured to be coupled to a fluid source to thereby introduce a fluid into the gap and into the passageway of the spindle.

Description

BACKGROUND

Vibrational drilling operations, such as sonic drilling operations, typically utilize a drill bit that is vibrated in the axial direction. The drill bit is also typically pushed with an axial force and simultaneously rotated. These three combined forces enable the drill bit to penetrate soil particles which are fluidized by the vibration of the drill bit. When the drill bit encounters rock, the drill bit fractures the rock face, creating rock dust and small particles which the drill bit can then advance through.

Many sonic drilling operations use bearings in the drill head. However, the bearings can fail in some cases, which can lead to significant down time for repair.

SUMMARY

In one embodiment, the invention is a drill head that utilizes a fluid to lubricate and/or maintain alignment of the drill head such that bearings are not necessarily needed. More particularly, in one embodiment the invention is a drill head system including a drill head having a spindle configured to be operatively coupled to a vibration source to cause the spindle to vibrate in an axial direction, the spindle having a passageway. The system further includes a sleeve receiving said spindle therein with a gap therebetween. The sleeve is configured to be coupled to a fluid source to thereby introduce a fluid into the gap and into the passageway of the spindle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view of one embodiment of a drilling system;

FIG. 2 is detail side view of a drill head indicated in FIG. 1;

FIG. 3 is a top view of the drill head of FIG. 2;

FIG. 4 is a cross section along line 4-4 of FIG. 3;

FIG. 5 is an exploded view of the drill head of FIG. 4; and

FIG. 6 shows the drill head of FIG. 4 connected to a vibration source, a water source and a drill bit.

DETAILED DESCRIPTION

FIG. 1 is a schematic representation of a drilling system 10 including a drill bit 12 positioned at the distal axial end of a drilling pipe or stringer pipe 14. The stringer pipe 14 can be generally solid, or in some cases the stringer pipe 14 is hollow and has a central opening to allow coring operations if desired. The stringer pipe 14 is, in turn, operatively connected to a vibration source 16 via a water swivel, drill head or drill head system 18. The drilling system 10 and/or vibration source 16 can also include mechanisms, and/or be coupled to mechanisms and/or be configured to cause the stringer pipe 14 and drill bit 12 to be pushed axially (with a force and/or displacement greater than the imparted vibration) and simultaneously rotated to aid in drilling operations. Such axial and rotational drive mechanism are disclosed for example in U.S. Pat. No. 5,771,985, entitled Earth Penetrating Apparatus for Obtaining Sediment Samples, Driving Instrument Probes, Pilings or Sheet Pilings; and/or U.S. Pat. No. 6,542,966, entitled Drive System for Inserting and Extracting Elongate Members Into the Earth; and/or U.S. Pat. No. 8,342,263 entitled Vibratory Drill Head Mounting and Rotation Coupling System. The entire contents of all of these patents are incorporated by reference herein. An example of a drill rig is a SDC500-28EA drill rig sold by Sonic Drill Corporation of Bellingham, Wash.

The vibration source 16 can impart vibrations of various frequencies to the drill head system 18/stringer pipe 14/drill bit 12, such as frequencies between about 15 Hz and about 350 Hz, and more particularly in one case, between about 50 Hz and about 150 Hz. An example of a vibration source is a SONICOR 50K drill head sold by Sonic Drill Corporation of Bellingham, Wash., or is provided in U.S. Pat. No. 4,553,443, entitled High Frequency Vibratory Systems for Earth Boring, and/or U.S. Pat. No. 4,890,682, entitled Apparatus for Vibrating a Pipe String in a Borehole; and/or U.S. Pat. No. 7,607,498 entitled Assembly and Method for Discharging Fluid Into a Drill String of a Rotary-vibratory Drill. The entire contents of each of those patents which are incorporated herein. All or some of the drilling frequencies can in some cases be considered to be sonic frequencies, and thus the drilling system 10 can be considered a sonic drilling system/recirculation system and the drill head 18 considered a sonic drill head/water swivel.

In some cases the drilling system 10 is used in conjunction with a drilling fluid 20 such as compressed air, drill mud, liquid water or the like which can be utilized to provide lubrication and carry dust, particles and cuttings away from the drill bit 12. In the configuration shown in FIG. 1, the drilling system 10 utilizes a recirculating, closed-circuit system 22 for circulating the drilling fluid. In particular, fluid 20 can flow down the central opening of stringer pipe 14 and exit at the distal end thereof, and flow into the surrounding ground surface 24. The discharged fluid 20 then flows or percolates upwardly due to the vibration forces of the adjacent stringer pipe 14 and other forces such that the fluid 20 enters, and can be collected in, a collection pot 26 positioned at the surface of the ground 24 about or adjacent to the stringer pipe 14. The collection pot 26 is, in turn, fluidly coupled to a settling tank 28 such that the drilling fluid 20 can thus be recaptured for further use.

The captured fluid 20 is allowed to collect in the settling tank 28, which can have baffles positioned therein (not shown) to decrease turbulence and/or remove large impurities. In addition if desired, an operator can periodically shovel and remove sludge from the bottom of the settling tank 28. Fluid 20 from the settling tank 28 is then passed through a pump 30 and a de-sander, filter 32 or the like to another settling tank 28. The drilling fluid 20 can then be passed through various other tanks 28, pumps 30, filters and/or de-sanders 32 and ultimately re-introduced, via a hose, tube, conduit or the like 58, into the drill head/water swivel 18 for re-use in drilling operations as will be described in greater detail below.

FIG. 2 is a side view of the water swivel 18 of the system 10 of FIG. 1, and FIG. 3 is a top view of the water swivel 18. With reference to FIGS. 4 and 5, the water swivel 18 can include, in general, a spindle 34, a sleeve or housing 36 configured to receive the spindle 34 therein, and pair of generally annular seal retainers 38 coupled to the top and bottom, respectively of the sleeve 36. The water swivel 18 and its parts can be made of various materials, such as metal (more particularly aluminum in one case), metal alloys, composite material and other materials that are sufficiently strong and durable to provide the functionality specified herein. The spindle 34 can be generally cylindrical in shape and include an internal passageway or set of internal passageways 40. Each passageway 40 can have a radially extending portion or portions 42 that extend from a radially outer surface of the spindle 34, inwardly to a central axis of the spindle 34, as shown in FIG. 3. As can be seen in FIGS. 4-6, each radially-extending portion 42 of the passageways 40 can also extend or have portions that extend generally axially (downwardly) at a generally 45 degree angle.

In the illustrated embodiment, the passageway 40 and spindle 34 includes three radially-extending portions 42 spaced 120 degrees apart from each other, as shown in FIG. 3. The passageway 40 of the spindle 34 can also include an axially-extending portion 44 in fluid communication with the radially-extending portions 42. The axially-extending portion 44 of the passageway 40 extends downwardly from its intersection with the radially-extending portions 42, and exits/intersects a lower/distal end of the spindle 34. In this manner the spindle 34 includes an exit opening 46 at an axial center thereof and at a distal end of the spindle 34. However, the arrangement of the passageway 40 of the spindle 34, including the various axially-extending 44 and radially-extending 42 portions, can be varied as desired from that specifically shown herein. For example, the number, arrangement, spacing and configuration of the radially-extending portions 42 and/or axially-extending portion 44 can be varied. The spindle 34 also includes a flange 48 at its upper axial end for connection to the vibration source, as shown in FIG. 6.

The sleeve 36 is generally annular and has a central axially-extending opening 50. An inner protrusion 51 is positioned in and/or defines the opening 50 and has a radially-innermost inner surface that is slightly larger than the radially-outermost outer surface of the spindle 34 such that a gap 52 is positioned between the protrusion 51/sleeve 36 and the spindle 34. The sleeve 36 includes a plurality of passageways 54 extending radially through the protrusion 51 (or extending through its own protrusion 51) from an outer surface of the sleeve 36 to a radially inner surface thereof. In the illustrated embodiment the sleeve 36 includes two passageways 54 extending therethrough, each spaced apart 180 degrees in top view, although the arrangement and spacing of the passageways 54 of the sleeve 36 can be varied as desired. A port 56 can be positioned adjacent to a radially outer end of each passageway 54 such that a hose, tube, conduit or the like 58 can be fluidly coupled to each passageway 54, and in turn fluidly coupled to or form part of the fluid distribution system 22 as shown in FIG. 1.

The water swivel 18 can include a first seal system 60 in the form of or including a plurality of annular lip seals 62, located on the first (upper) axial side of the water swivel 18 (positioned at a first axial side of a radially outermost portion of the passageway 40 of the spindle 34). A second seal system 64, in the form of or including a plurality of lip seals 62, can be positioned at a second (lower) axial side of the water swivel 18 (positioned at a second, opposite axial side of the radially outermost portion of the passageway 40 of the spindle 34). The lip seals 62 extend radially between the spindle 34 and the sleeve 36 to form a fluid-tight connection to prevent fluid 20 from escaping the water swivel 18. The spindle 34 thus sealingly engages the sleeve 36 at portions of the spindle 34 spaced axially away from a radially outermost portion of the passageway 40 of the spindle 34. If desired or rings or seals, such as V-rings made of various materials including aluminum, can be positioned between the two sets of lip seals 60. Moreover, an environmentally friendly grease or other lubricant can be injected into the water swivel 18, such as the gap 52 and extend 360 degrees about the water swivel 18/gap 52.

The pair of sleeve retainers 38 can be coupled to the sleeve 34, and each includes an inner flange portion 68 which can engage the axially outermost (lower and upper) seal of the adjacent lip seals 60 to thereby retain the lip seals 60 in place. Each seal retainer 38 can also include a bushing or gasket 70 (such as a copper bushing) on its radially inner face, where each bushing 70 is positioned and configured to at least partially or fully sealingly engage the spindle 34 to further provide fluid isolation to the water swivel 18. A finishing plate 72 is coupled to a bottom of the spindle 34, and a series of connectors or fasteners 74 are used to secure the components of the water swivel 18 together.

In order to utilize the drilling system 10, the water swivel 18 is operatively/mechanically coupled to the vibration source 16, as shown in FIGS. 1 and 6 at one (an upper) axial end. The water swivel 18 is then operatively/mechanically coupled to a stringer pipe 14/drill bit 12 at the opposite (lower) axial end. Next, pressurized fluid 20 is introduced into the sleeve 34 via the hoses 58, which causes fluid 20 to flow radially inwardly through the passageway 54 of the sleeve 36. The fluid 20 then enters and fills the gap 52 between the sleeve 36 and the spindle 34, but is prevented from escaping axially by the seal systems 60, 64 and the bushings 70. Fluid 20 is thereby forced/directed into the passageway 40 of the spindle 34, and exits by flowing downwardly, exiting via the stringer pipe 14 and the drill bit 12, as described above in the context of FIG. 1.

In this manner, as the spindle 34 is vibrated, moved axially and rotated, the fluid 20 in the gap 52 acts as a lubricant and spacer between the spindle 34 and the sleeve 36, and the spindle 34 “floats” in the sleeve 36. In addition, the fluid 20 naturally flows about the spindle 34 and seeks equalized pressure, thereby helping to keep the spindle 34 radially aligned in the sleeve 36. The fluid 20 in the gap 52 also helps to isolate the sleeve 36 (and thus other components in the drilling system 18) from the vibrational forces of the spindle 34, thereby extending the operating life of the other components. The gap 52 can extend about an entire perimeter (i.e., 360 degrees) of the spindle 34 to provide complete water encapsulation, lubrication and alignment. In this manner, the fluid 20 provides lubrication, alignment and vibration isolation functions to the water swivel 18 without the use of bearings, which can be prone to failure and breaking, and require frequent replacement. In addition, should the water swivel 18 require maintenance, the seal retainers 38 are easily removed, providing access to the bushing 70, seals 62 and spindle 34 for inspection, repair and replacement.

In addition, the system 10 is arranged and configured such that the fluid 20 is introduced, at its upstream position, to the drilling system 10/drill head system 18 at position below the vibration source 16 (e.g. below with respect to a gravitational frame of reference or with respect to a general direction of the flow of fluid 20 through the drilling system 10/drill head system 10). By having fluid 20 introduced below the vibration source 16 and other upstream components, the fluid 20 bypasses the vibration source 16 and other upstream components. This reduces chances for fluid leaks, fouling or contamination of the fluid 20, rusting and wear/tear on the upstream components, etc.

Having described the invention in detail and by reference to certain embodiments, it will be apparent that modifications and variations thereof are possible without departing from the scope of the invention.

Claims

1. A drill head system comprising a drill head having: a spindle configured to be operatively coupled to a vibration source to cause said spindle to vibrate in an axial direction, said spindle having a passageway; anda sleeve receiving said spindle therein with a gap therebetween, wherein said sleeve is configured to be coupled to a fluid source to thereby introduce a fluid into said gap and into said passageway of said spindle.

2. The system of claim 1 wherein said gap extends about an entire outer perimeter of said spindle.

3. The system of claim 1 wherein said sleeve includes a passageway that extends from a radially outer surface of said sleeve to said gap to thereby enable said fluid to be introduced into said gap and into said passageway of said sleeve.

4. The system of claim 3 wherein said passageway of said sleeve extends generally radially.

5. The system of claim 1 wherein said passageway of said spindle extends from a radially outer surface of said spindle to an axial center thereof and includes an exit opening at a distal axial end of said spindle.

6. The system of claim 1 wherein said spindle sealingly engages said sleeve at portions of said spindle spaced axially away from a radially outermost position of said passageway of said spindle.

7. The system of claim 1 further comprising a first seal system positioned between said spindle and said sleeve at a first axial side of a radially outermost position of said passageway of said spindle, and a second seal system positioned between said spindle and said sleeve at a second, opposite axial side of said radially outermost position of said passageway of said spindle.

8. The system of claim 7 further comprising a first seal retainer coupled to said sleeve and engaging and retaining said first seal system, and a second seal retainer coupled to said sleeve and engaging and retaining said second seal system.

9. The system of claim 1 further comprising said vibration source operatively coupled to said spindle to cause said spindle to vibrate in an axial direction, and further comprising said fluid positioned in said gap and extending about an entire perimeter of about said spindle.

10. The system of claim 9 wherein said vibration source is configured to vibrate at a frequency between about 15 Hz and about 350 Hz.

11. The system of claim 9 further comprising a stringer pipe operatively coupled to the spindle, an axial advancement mechanism configured to axially advance the stringer pipe and a rotational mechanism configured to rotate the stringer pipe.

12. The system of claim 1 further comprising a fluid circulation system configured to capture at least part of said fluid which exits said spindle and to reintroduce said captured fluid to said drill head.

13. A drill head system comprising a drill head having: a spindle configured to be operatively coupled to a vibration source to cause said spindle to vibrate in an axial direction; anda sleeve receiving said spindle therein with a gap therebetween, wherein said sleeve includes a passageway that extends from a radially outer surface of the sleeve to the gap to thereby enable fluid to be introduced into said gap.

14. The drill head system of claim 13 wherein said spindle has a passageway in fluid communication with said gap.

15. The drill head system of claim 14 wherein said passageway of said spindle has a portion that extends from a radially outer surface of said spindle and a portion that is in fluid communication with an axial end surface of said spindle.

16. A method for operating a drill head system comprising: accessing a drill head having a spindle with a passageway, and a sleeve receiving said spindle therein with a gap therebetween;operatively coupling said spindle to a vibration source configured to cause said spindle to vibrate in an axial direction; andcoupling said sleeve to a fluid source to thereby introduce a fluid into said gap and into said passageway of said spindle.

17. The method of claim 16 wherein said sleeve includes a passageway that extends from a radially outer surface of said sleeve to said gap, and wherein said fluid source is coupled to said passageway of said sleeve to thereby introduce said fluid into said gap.

18. The method of claim 16 wherein said fluid introduced into said passageway of said spindle exits said spindle at a distal axial end thereof.

19. The method of claim 16 further comprising coupling a drill bit coupled to said spindle such that vibrations of said spindle are transmitted to said drill bit, and wherein the method further includes rotating and axially advancing the drill bit.

20. A drill head system comprising: a vibration source;a drill head having a spindle operatively coupled to the vibration source to cause said spindle to vibrate in an axial direction;an advancement mechanism configured to cause the drill head to be advanced axially and rotated; anda fluid system configured to introduce fluid into said spindle at a position below said vibration source.