US20100000797A1 - Drilling tool - Google Patents
Drilling tool Download PDFInfo
- Publication number
- US20100000797A1 US20100000797A1 US12/525,189 US52518908A US2010000797A1 US 20100000797 A1 US20100000797 A1 US 20100000797A1 US 52518908 A US52518908 A US 52518908A US 2010000797 A1 US2010000797 A1 US 2010000797A1
- Authority
- US
- United States
- Prior art keywords
- drilling tool
- drill
- tool
- drill rod
- drilling
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Abandoned
Links
- 238000005553 drilling Methods 0.000 title claims abstract description 56
- 239000011435 rock Substances 0.000 claims abstract description 7
- 239000000463 material Substances 0.000 description 9
- 230000001681 protective effect Effects 0.000 description 3
- 235000019994 cava Nutrition 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000007779 soft material Substances 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
Images
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/10—Wear protectors; Centralising devices, e.g. stabilisers
- E21B17/1078—Stabilisers or centralisers for casing, tubing or drill pipes
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/18—Pipes provided with plural fluid passages
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21B—EARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B21/00—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor
- E21B21/12—Methods or apparatus for flushing boreholes, e.g. by use of exhaust air from motor using drilling pipes with plural fluid passages, e.g. closed circulation systems
Definitions
- the invention relates to a drilling tool for drilling soft and fragmented rock.
- a grooved guide tube or a separate protective tube is used, which is either left in the hole or withdrawn from the hole after the drilling.
- the intention is to prevent the material surrounding the hole from caving in to enable the withdrawal of the drill bit from the hole as the last action.
- a prior art drawback is that when a grooved guide tube is used, the grooved portions of the tube may break the wall of the hole, which makes the hole cave in regardless of the intention to the contrary. Furthermore, if a separate protective tube is used, extra equipment is required for installing and disassembling the protective tubes.
- the object of the present invention is to provide a drilling tool for preventing better than previously the caving in of the hole walls when fragmented or soft material is being drilled.
- the drilling tool of the invention is characterized in that it comprises a portion having a round cross section and a smooth surface and positioned substantially symmetrically relative to the middle axis of a drill rod and comprising, at least at the end intended to be positioned towards the rock drill, a part converging towards the axis of the drill rod, and that it comprises, for rinsing medium, through-going conduits that terminate in said converging part.
- the drilling tool is a part that has a smooth outer surface, is positioned symmetrically relative to the middle axis of the drill rod and comprises converging ends in such a manner that during the rotation of the drill rod it penetrates through the material that tends to cave in and simultaneously compresses and grinds the material tightly against the wall of the drill hole.
- the tool of the invention is further characterized in that it comprises through-going longitudinal conduits, through which the rinsing medium is allowed to flow away from the drill hole.
- An advantage of the invention is that during the drilling of soft or fragmented material, the drill hole can be kept open, as the tool compresses the detaching material tightly into the wall of the drill hole.
- a further advantage of the invention is that since the flow of rinsing medium is arranged through the drilling tool, and not along the grooves on its outer surface, the flow of rinsing medium does not corrode or detach material from the wall of the drill hole very easily, and thus does not cause cave-ins very easily in a ready-made hole.
- a still further advantage of the invention is that if for some reason the drill hole caves in, it can be opened quite easily by means of the drilling tool.
- FIG. 1 schematically shows an embodiment of a drilling tool installed in a drill rod
- FIG. 2 schematically shows an embodiment of a drilling tool seen from above
- FIG. 3 schematically shows the drilling tool shown in FIG. 2 in the longitudinal direction in section along line A-A,
- FIG. 4 shows another embodiment of the tool disclosed in the invention.
- FIG. 5 shows still another embodiment of the tool disclosed in the invention.
- FIG. 1 shows a drilling tool of the invention installed in a drill rod. It shows a short drill rod 1 , one end of which comprises an external thread 2 for fastening a drill bit, the other end comprising an internal thread 3 for fastening a second drill rod.
- a drilling tool 4 is fastened onto the drill rod 1 .
- the drilling tool 4 is installed in a separate short part of the drill rod intended to be installed between a normal drill bit and a drill rod of a normal length.
- each end of the drilling tool 4 is provided with a converging part 4 a, which is connected to the drill rod at each end thereof and, correspondingly, to the middle part of the drilling tool in a rounded manner in a manner generating a smooth, even surface.
- FIG. 1 further shows openings 5 at the converging part 4 a at both ends of the drilling tool 4 .
- the openings 5 are interconnected by means of a conduit described later in connection with FIG. 3 , allowing rinsing medium to flow between the ends of the drilling tool 4 without the rinsing medium having to flow from between the outer surface of the drilling tool and the surface of the hole.
- a rinsing medium flow may cause caving in of the walls of a hole.
- FIG. 2 schematically shows a drilling tool seen from the end.
- the cross section of the drilling tool 4 is substantially cylindrical and the tool has a smooth surface. Its diameter is dimensioned in a manner making it slightly smaller than the outer diameter of the drill bit intended to be used therewith. The reason for this is to allow the tool to pass through a hole made by the drill bit in a hole drilled in a potentially hard rock. It also shows how a plurality of conduits 5 a lead through the drilling tool 4 for allowing rinsing medium to flow out of the drill hole.
- FIG. 2 also shows a conduit 1 a in the middle of the drill rod 1 , along which conduit the rinsing medium flows to the drill bit and further through conduits therein to the drill hole for transporting drilling residue out of the drill hole.
- FIG. 3 schematically shows the drilling tool according to FIG. 2 in the longitudinal direction in section along line A-A.
- the openings 5 are at the ends of the conduit 5 a inside the drilling tool.
- a suitable number of such conduits e.g. 6 or less or more, may be positioned around the axis of the drilling tool. It is essential that the number and the common cross-sectional area of the openings are sufficient for the outflow of the rinsing medium and the material transported therewith.
- the cross section of the conduits passing through the drilling tool may be, not only round, but also of another shape, such as angular, oval, etc.
- the edges of the opening may be inclined inwards, allowing them to push the material outwards from the openings when hitting it.
- FIG. 4 schematically shows another embodiment of drilling tool.
- the drilling tool is arranged at one end of a drill rod 1 of a conventional length, close to the external thread 2 such that it is positioned almost immediately after the drill bit, when the drill bit is fastened to the drill rod 1 .
- the control and operation of the drilling rig are as in normal drilling, and no separate short drilling for using exclusively the drilling tool is required at the beginning of the drilling.
- FIG. 5 schematically shows still another embodiment of a drilling tool.
- the drilling tool is composed as an entity integrated into the drill bit 6 .
- the conduits for removing rinsing medium and drilling residue naturally pass straight through the drill bit and the tool part.
- the drilling tool may be fastened onto the drill rod in a plurality of manners known per se. For example, the drilling tool may be pushed onto the drill rod and then welded thereto at its ends, followed by finishing of the surface suitably smooth. Alternatively, the drilling tool, preferably comprising only a short drill rod, may be directly machined as a solid entity, for example. Other manners of manufacture and fastening are also usable.
Landscapes
- Engineering & Computer Science (AREA)
- Geology (AREA)
- Life Sciences & Earth Sciences (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- Mechanical Engineering (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
- Processing Of Stones Or Stones Resemblance Materials (AREA)
- Drilling Tools (AREA)
Abstract
The invention relates to a drilling tool for drilling soft and fragmented rock. The drilling tool disclosed in the invention comprises a portion having a round cross section and a smooth surface and positioned substantially symmetrically relative to the middle axis of a drill rod and comprising, at its end, a converging part through which conduits pass for rinsing medium.
Description
- The invention relates to a drilling tool for drilling soft and fragmented rock.
- Presently, when soft and fragmented rock is drilled, typically either a grooved guide tube or a separate protective tube is used, which is either left in the hole or withdrawn from the hole after the drilling. The intention is to prevent the material surrounding the hole from caving in to enable the withdrawal of the drill bit from the hole as the last action.
- A prior art drawback is that when a grooved guide tube is used, the grooved portions of the tube may break the wall of the hole, which makes the hole cave in regardless of the intention to the contrary. Furthermore, if a separate protective tube is used, extra equipment is required for installing and disassembling the protective tubes.
- The object of the present invention is to provide a drilling tool for preventing better than previously the caving in of the hole walls when fragmented or soft material is being drilled.
- The drilling tool of the invention is characterized in that it comprises a portion having a round cross section and a smooth surface and positioned substantially symmetrically relative to the middle axis of a drill rod and comprising, at least at the end intended to be positioned towards the rock drill, a part converging towards the axis of the drill rod, and that it comprises, for rinsing medium, through-going conduits that terminate in said converging part.
- It is an essential idea of the invention that the drilling tool is a part that has a smooth outer surface, is positioned symmetrically relative to the middle axis of the drill rod and comprises converging ends in such a manner that during the rotation of the drill rod it penetrates through the material that tends to cave in and simultaneously compresses and grinds the material tightly against the wall of the drill hole.
- The tool of the invention is further characterized in that it comprises through-going longitudinal conduits, through which the rinsing medium is allowed to flow away from the drill hole.
- An advantage of the invention is that during the drilling of soft or fragmented material, the drill hole can be kept open, as the tool compresses the detaching material tightly into the wall of the drill hole.
- A further advantage of the invention is that since the flow of rinsing medium is arranged through the drilling tool, and not along the grooves on its outer surface, the flow of rinsing medium does not corrode or detach material from the wall of the drill hole very easily, and thus does not cause cave-ins very easily in a ready-made hole.
- A still further advantage of the invention is that if for some reason the drill hole caves in, it can be opened quite easily by means of the drilling tool.
- The invention will be described in more detail in the attached drawings, wherein
-
FIG. 1 schematically shows an embodiment of a drilling tool installed in a drill rod, -
FIG. 2 schematically shows an embodiment of a drilling tool seen from above, -
FIG. 3 schematically shows the drilling tool shown inFIG. 2 in the longitudinal direction in section along line A-A, -
FIG. 4 shows another embodiment of the tool disclosed in the invention, and -
FIG. 5 shows still another embodiment of the tool disclosed in the invention. - In the figures, some embodiments of the invention are shown in a simplified manner for the sake of clarity. In the figures, like parts are denoted with the same reference numerals.
-
FIG. 1 shows a drilling tool of the invention installed in a drill rod. It shows ashort drill rod 1, one end of which comprises anexternal thread 2 for fastening a drill bit, the other end comprising aninternal thread 3 for fastening a second drill rod. Adrilling tool 4 is fastened onto thedrill rod 1. In this embodiment, thedrilling tool 4 is installed in a separate short part of the drill rod intended to be installed between a normal drill bit and a drill rod of a normal length. Furthermore, each end of thedrilling tool 4 is provided with aconverging part 4 a, which is connected to the drill rod at each end thereof and, correspondingly, to the middle part of the drilling tool in a rounded manner in a manner generating a smooth, even surface. The purpose of this is to make the shape of thedrilling tool 4, when it hits the wall of a caved-in drill hole or a drill hole tending to cave in, compress the detaching or detached material against the wall of the drill hole, its cylindrical part, when the drill rod is rotating, as if compressing the wall firmly and tightly together.FIG. 1 further showsopenings 5 at theconverging part 4 a at both ends of thedrilling tool 4. Theopenings 5 are interconnected by means of a conduit described later in connection withFIG. 3 , allowing rinsing medium to flow between the ends of thedrilling tool 4 without the rinsing medium having to flow from between the outer surface of the drilling tool and the surface of the hole. Typically, such a rinsing medium flow may cause caving in of the walls of a hole. -
FIG. 2 schematically shows a drilling tool seen from the end. The cross section of thedrilling tool 4 is substantially cylindrical and the tool has a smooth surface. Its diameter is dimensioned in a manner making it slightly smaller than the outer diameter of the drill bit intended to be used therewith. The reason for this is to allow the tool to pass through a hole made by the drill bit in a hole drilled in a potentially hard rock. It also shows how a plurality ofconduits 5 a lead through thedrilling tool 4 for allowing rinsing medium to flow out of the drill hole.FIG. 2 also shows aconduit 1 a in the middle of thedrill rod 1, along which conduit the rinsing medium flows to the drill bit and further through conduits therein to the drill hole for transporting drilling residue out of the drill hole. -
FIG. 3 schematically shows the drilling tool according toFIG. 2 in the longitudinal direction in section along line A-A. As it shows, theopenings 5 are at the ends of theconduit 5 a inside the drilling tool. A suitable number of such conduits, e.g. 6 or less or more, may be positioned around the axis of the drilling tool. It is essential that the number and the common cross-sectional area of the openings are sufficient for the outflow of the rinsing medium and the material transported therewith. The cross section of the conduits passing through the drilling tool may be, not only round, but also of another shape, such as angular, oval, etc. Similarly, the edges of the opening may be inclined inwards, allowing them to push the material outwards from the openings when hitting it. -
FIG. 4 schematically shows another embodiment of drilling tool. Here, the drilling tool is arranged at one end of adrill rod 1 of a conventional length, close to theexternal thread 2 such that it is positioned almost immediately after the drill bit, when the drill bit is fastened to thedrill rod 1. This being so, the control and operation of the drilling rig are as in normal drilling, and no separate short drilling for using exclusively the drilling tool is required at the beginning of the drilling. -
FIG. 5 schematically shows still another embodiment of a drilling tool. Here, the drilling tool is composed as an entity integrated into thedrill bit 6. Here, the conduits for removing rinsing medium and drilling residue naturally pass straight through the drill bit and the tool part. - In the above description and in the drawings, the invention is only described by way of example and in no way restricted thereto. In some cases, the characteristics disclosed in the present application may be utilized as such, irrespective of other characteristics. On the other hand, when desired, the characteristics disclosed in the present application may be combined for generating different combinations. The drilling tool may be fastened onto the drill rod in a plurality of manners known per se. For example, the drilling tool may be pushed onto the drill rod and then welded thereto at its ends, followed by finishing of the surface suitably smooth. Alternatively, the drilling tool, preferably comprising only a short drill rod, may be directly machined as a solid entity, for example. Other manners of manufacture and fastening are also usable.
- The drawings and the related description are only intended to illustrate the idea of the invention. The details of the invention may vary within the scope of the claims.
Claims (5)
1. A drilling tool for drilling soft and fragmented rock, which tool comprises a portion having a round cross section and a smooth surface and positioned substantially symmetrically relative to the middle axis of a drill rod and comprising, at least at the end intended to be positioned towards the rock drill, a part converging towards the axis of the drill rod, and that the tool comprises, for rinsing medium, through-going conduits that terminate in said converging part, wherein the largest outer diameter of the tool is dimensioned smaller than the outer diameter of the drill bit intended to be used therewith.
2. A drilling tool as claimed in claim 1 , wherein the drilling tool is a part separate from the drill bit and both of its ends are provided with a part that converges towards the axis of the drill rod and that the conduits for the rinsing medium lead from the converging part to an opposite, converging part.
3. A drilling tool as claimed in claim 2 , wherein the middle part of the drilling tool is substantially cylindrical and that one end of the drill rod is provided with an external thread, the other being provided similarly with an internal thread for connecting the drill bit and the drill rods, respectively, thereto.
4. A drilling tool as claimed in claim 2 , wherein the drilling tool is installed at the end on the side of the external thread of the drill rod of a normal length.
5. A drilling tool as claimed in claim 1 , wherein the drilling tool is a part integrated into the drill bit.
Applications Claiming Priority (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
FI20075066 | 2007-02-01 | ||
FI20075066A FI20075066L (en) | 2007-02-01 | 2007-02-01 | Drilling tool |
PCT/FI2008/050028 WO2008092994A1 (en) | 2007-02-01 | 2008-01-30 | Drilling tool |
Publications (1)
Publication Number | Publication Date |
---|---|
US20100000797A1 true US20100000797A1 (en) | 2010-01-07 |
Family
ID=37832221
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
US12/525,189 Abandoned US20100000797A1 (en) | 2007-02-01 | 2008-01-30 | Drilling tool |
Country Status (10)
Country | Link |
---|---|
US (1) | US20100000797A1 (en) |
EP (1) | EP2137373A1 (en) |
JP (1) | JP2010518278A (en) |
CN (1) | CN101600848A (en) |
AU (1) | AU2008211808B2 (en) |
CA (1) | CA2675842A1 (en) |
FI (1) | FI20075066L (en) |
RU (1) | RU2009132669A (en) |
WO (1) | WO2008092994A1 (en) |
ZA (1) | ZA200905044B (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11134933B2 (en) | 2004-03-19 | 2021-10-05 | St. Jude Medical, Cardiology Division, Inc. | Multi-layer braided structures for occluding vascular defects |
Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2126075A (en) * | 1936-08-24 | 1938-08-09 | Martha H Wright | Drill collar |
US3371729A (en) * | 1965-10-12 | 1968-03-05 | Charles J. Carr | Circulating stabilizer-reamer and bumper |
US4102418A (en) * | 1977-01-24 | 1978-07-25 | Bakerdrill Inc. | Borehole drilling apparatus |
US20060144620A1 (en) * | 2002-12-21 | 2006-07-06 | Iain Cooper | Wellbore consolidating tool for rotary drilling applications |
US20100300761A1 (en) * | 2007-12-04 | 2010-12-02 | Earles Ronald G | Apparatus and methods to optimize fluid flow and performance of downhole drilling equipment |
Family Cites Families (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS51134002A (en) * | 1975-05-16 | 1976-11-20 | Matsushita Electric Ind Co Ltd | Power supply alarm unit |
JPS5944485A (en) * | 1982-09-07 | 1984-03-12 | 玉田 真作育 | Casingless boring apparatus |
JPS63100590A (en) * | 1986-10-17 | 1988-05-02 | Nec Corp | Ic card |
DE3828335C1 (en) * | 1988-08-20 | 1989-11-30 | Friedr. Ischebeck Gmbh, 5828 Ennepetal, De | |
FI103430B1 (en) * | 1994-10-05 | 1999-06-30 | Valto Ilomaeki | Drilling unit and method for drilling a hole in several different soils |
JP3463990B2 (en) * | 2000-07-03 | 2003-11-05 | 俊浩 福政 | Drilling tool and drilling method using the same |
-
2007
- 2007-02-01 FI FI20075066A patent/FI20075066L/en not_active Application Discontinuation
-
2008
- 2008-01-30 US US12/525,189 patent/US20100000797A1/en not_active Abandoned
- 2008-01-30 CA CA002675842A patent/CA2675842A1/en not_active Abandoned
- 2008-01-30 JP JP2009547720A patent/JP2010518278A/en active Pending
- 2008-01-30 AU AU2008211808A patent/AU2008211808B2/en not_active Ceased
- 2008-01-30 EP EP08709297A patent/EP2137373A1/en not_active Withdrawn
- 2008-01-30 WO PCT/FI2008/050028 patent/WO2008092994A1/en active Application Filing
- 2008-01-30 CN CNA2008800039343A patent/CN101600848A/en active Pending
- 2008-01-30 RU RU2009132669/03A patent/RU2009132669A/en not_active Application Discontinuation
-
2009
- 2009-07-20 ZA ZA200905044A patent/ZA200905044B/en unknown
Patent Citations (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2126075A (en) * | 1936-08-24 | 1938-08-09 | Martha H Wright | Drill collar |
US3371729A (en) * | 1965-10-12 | 1968-03-05 | Charles J. Carr | Circulating stabilizer-reamer and bumper |
US4102418A (en) * | 1977-01-24 | 1978-07-25 | Bakerdrill Inc. | Borehole drilling apparatus |
US20060144620A1 (en) * | 2002-12-21 | 2006-07-06 | Iain Cooper | Wellbore consolidating tool for rotary drilling applications |
US20100300761A1 (en) * | 2007-12-04 | 2010-12-02 | Earles Ronald G | Apparatus and methods to optimize fluid flow and performance of downhole drilling equipment |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US11134933B2 (en) | 2004-03-19 | 2021-10-05 | St. Jude Medical, Cardiology Division, Inc. | Multi-layer braided structures for occluding vascular defects |
Also Published As
Publication number | Publication date |
---|---|
CA2675842A1 (en) | 2008-08-07 |
WO2008092994A1 (en) | 2008-08-07 |
ZA200905044B (en) | 2010-04-28 |
JP2010518278A (en) | 2010-05-27 |
FI20075066A0 (en) | 2007-02-01 |
EP2137373A1 (en) | 2009-12-30 |
CN101600848A (en) | 2009-12-09 |
FI20075066L (en) | 2008-08-02 |
RU2009132669A (en) | 2011-03-10 |
AU2008211808A1 (en) | 2008-08-07 |
AU2008211808B2 (en) | 2011-04-28 |
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Legal Events
Date | Code | Title | Description |
---|---|---|---|
AS | Assignment |
Owner name: SANDVIK MINING & CONSTRUCTION OY, FINLAND Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:KATAJA, AULIS;KALLIOMAKI, JORMA;BOURNAZOS, IOANNIS;REEL/FRAME:023403/0599 Effective date: 20090810 |
|
STCB | Information on status: application discontinuation |
Free format text: ABANDONED -- FAILURE TO RESPOND TO AN OFFICE ACTION |