GB2207158A - Drilling or coring tool - Google Patents
Drilling or coring tool Download PDFInfo
- Publication number
- GB2207158A GB2207158A GB08812873A GB8812873A GB2207158A GB 2207158 A GB2207158 A GB 2207158A GB 08812873 A GB08812873 A GB 08812873A GB 8812873 A GB8812873 A GB 8812873A GB 2207158 A GB2207158 A GB 2207158A
- Authority
- GB
- United Kingdom
- Prior art keywords
- core
- drill
- drilling
- coring
- tool
- 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.)
- Withdrawn
Links
- 238000005553 drilling Methods 0.000 title claims abstract description 26
- 239000003381 stabilizer Substances 0.000 claims abstract description 16
- 239000003129 oil well Substances 0.000 claims abstract description 14
- 239000010432 diamond Substances 0.000 claims abstract description 8
- 239000002131 composite material Substances 0.000 claims description 2
- 230000006641 stabilisation Effects 0.000 claims description 2
- 238000011105 stabilization Methods 0.000 claims description 2
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 6
- 229910052782 aluminium Inorganic materials 0.000 description 6
- 239000004411 aluminium Substances 0.000 description 6
- 239000000470 constituent Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000000284 extract Substances 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
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
- E21B29/00—Cutting or destroying pipes, packers, plugs or wire lines, located in boreholes or wells, e.g. cutting of damaged pipes, of windows; Deforming of pipes in boreholes or wells; Reconditioning of well casings while in the ground
-
- 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
- E21B10/00—Drill bits
- E21B10/26—Drill bits with leading portion, i.e. drill bits with a pilot cutter; Drill bits for enlarging the borehole, e.g. reamers
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Mechanical Engineering (AREA)
- Earth Drilling (AREA)
Abstract
A drilling tool or coring tool particularly for uncapping an oil well sealed by a packer or plug includes a body portion 17 with a coned end 18 formed with a thread 19 for attachment to a stabilizer unit. The drill bit has a lower portion 20 with a bore 21 in it into which is welded a screwed or otherwise fixed pilot drill 22 adapted to drill a four inch diameter pilot hole. To this drill is fitted a core-catcher 47. The drill bit has radial arms 25 (26) 27 and (28) which are formed without any diamonds or other cutters on their outside edges. In a second embodiment (not shown) the coring tool includes a pilot drill bit mounted on a shaft extending along the axis of a core cutter which has no diamonds mounted on its outer surface. <IMAGE>
Description
DRILLING OR CORING TOOL
This invention relates to a drilling or coring tool.
The invention has particular, but not exclusive, application in the uncapping of sealed oil well holes.
Oil well holes are sealed by use of a bung or packer which may comprise for example a layer of aluminium followed by a layer of rubber, followed by a further layer of aluminium. Other configurations and other materials are used including various metallic and resilient constituents.
An object of the invention is to provide a drilling or coring tool which is capable of drilling through and clearing or cutting a core through both the metallic and resilient constituents of the bung.
In accordance with the present invention a drilling or coring tool is provided, particularly for uncapping sealed oil wells, the tool comprising a composite drilling bit adapted to drill a small guide hole followed by a larger hole of the full diameter of the casing of the sealed well hole, or to drill and remove a core of a diameter less than that of the casing, the bit having no diamonds or cutters on its outer surfaces which may come into contact with the oil well casing wall.
Preferably the drilling tool is used in combination with a stabilizer to which it may be attached, the stabilizer having radially extending ''wings" or "pads" with wear resistant surfaces adapted to contact the casing walls and to provide stabilization of the drill bit during drilling of the bung.
Preferably the drilling tool has radial drilling cutters which extena the full required diameter of the casing. Alternatively a coring cutter may be used so as to cut and remove a core of the bung or packer.
If the drilling tool is a core cutter it is preferably cylindrical and has within it a drill shaft which carries the pilot drill bit, a centralizing plate being slidable on the shaft and within the core cutter.
The centralizing plate, which keeps the drill shaft running true, can slide up the shaft being pushed by the core as it is being drilled.
Preferably a core retaining ring is provided on the pilot drill bit shaft and also a core catcher may be provided on the internal surface of the coring tool or bit to retain and remove the core of the bung or packer. A core catcher may be provided to retain and remove the core of the bung or packer.
The pilot drill may be any conventional form of drill and may be attached to the body of the tool below the radial cutters.
The tool may have a tapered thread at one end for attachment to the stabilizer unit and the stabilizer may have a correspondingly tapered internally threaded conea surface.
In the accompanying drawings:
Figure 1 illustrates, in section, a well casing which has been capped by a bung or packer;
Figure 2 is a longitudinal section through a tool embodying the present invention;
Figure 3 is an underneath view of the same tool;
Figure 4 is a longitudinal section through a stabilizer unit for use with the invention;
Figure 5 is a plan view of the stabilizer unit;
Figure 6 is a section through a drilling or coring tool forming a second embodiment of the present invention.
In Figure 1 is shown a well hole 10 which is surrounded by conventional well hole casing 11, shown diagrammatically. The oil well hole is sealed by means of a bung 12 which has an aluminium layer 13 a rubber layer 14 and an aluminium cone or "bomb" 15 with a seal at 16.
In order to uncap the oil well it is necessary to drill through the bung and remove it. Conventionally this is done by sending a roller-cone bit down the hole, but difficulties are experienced in drilling through the rubber layer 14.
The drill bit in accordance with the invention shown in Figures 2 and 3 comprises a body portion 17 with a coned end 18 formed with a thread 19 for attachment to a stabilizer unit (shown in Figures 4 and 5). The drill bit has a lower portion 20 with a bore 21 in it, into which is welded a screwed or otherwise fixed pilot drill 22 adapted to drill a four inch diameter pilot hole. To this drill is fitted a core-catcher 47.
The drill bit has radial drill arms 25,26,27 and 28 which are formed without any diamonds or other cutters on their outside surfaces 29, 30, 31 and 32. Each of these radial drill arms has a cutting edge 33, 34, 35 and 36 respectively.
The radial arms may extend to a diameter of say 171/2 inches, assuming that a 171/2 inch diameter casing is employed.
The drill bit is stabilized by means of a stabilizer shown in Figures 4 and 5 consisting of a body 36 with radial fins 37,3S,39 and 40, each radial fin having a wear resistant curved outer surface 41,42,43 and 44 respectively.
At its lower end the stabilizer has an extension 45 with an internally threaded coned surface 46 to enable the drill bit to be attached to the stabilizer.
The stabilizer wear resistant surfaces will contact the drill casing and stabilize the bit during drilling without causing wear or marking on the drill casing.
It will be appreciated that there are no cutters or diamonds on the outside diameter of either the drill bit or the stabilizer and so no damage will be done to the oil well casing.
The wings 37,38,39 and 40 of the stabilizer are long-itudinally tapered by one degree to prevent debris from clogging up as the drilling operation is in progress.
by use of this drill bit it is possible to drill safely both through the aluminium and rubber of the bung and thus to remove the bung completely without damaging the oil well casing.
Once shear pins are fractured, the core catcher 47 on the pilot drill will prevent the remainder of the packer from falling down the well hole.
In Figure 6 of the drawings the tool 110 comprises a pilot drill 111 attached to a pilot drill shaft 117 which is screwed onto a back plate 119. behind the pilot drill 111 is an internal core catcher 112 and a retaining ring 113 adapted to catch the core to prevent it from dropping down the oil well hole.
An aluminium centralizing plate 116 is fitted onto the shaft 117 to keep the shaft running true. The plate 116 can slide up and down the shaft and may be pushed up the shaft by the core as it is being drilled.
The tool includes a coring bit having a coring bit crown 114 which has diamonds or other cutting media on the face 114A and internal diameter 114B only. Thus there are no diamonds or other cutting media on the face 114C which may come into contact with the oil well casing wall.
The diameter of the coring bit crown 114 and of its supporting coring barrel 120 may be chosen to suit the particular diameter of the oil well hole to be uncapped.
Inside the coring barrel 120 is an annular core catcher 115. The barrel 120 is screwed onto a back plate 119 so that the barrel may be removed to extract the core. The back plate 119 has holes 121 and 122 drilled through it, so that, optionally, internal flushing may be used.
Back plate 119 is welded onto a tapered threaded connection 118 which has a bore 123 connecting to the holes 121 and 122.
The complete unit is preferably used in conjunction with a stabilizing unit described in our co-pending application, mentioned above. This stabilizes the drill bit during drilling.
By using the tool shown in Figure 6, which cuts and extracts a core, a number of advantages result:
1. This is a cheaper method of drilling than with the full hole drilling.
2. brilling is achieved more quickly.
3. The method is safer because the full core is captured.
Claims (10)
1. A drilling or a coring tool, particularly for uncapping sealed oil wells, the tool comprising a composite drilling bit adapted to drill successively a small guide hole followed by a larger hole of the full diameter of the casing of the sealed well hole, or adapted to drill a small guide hole and then to remove a core of a diameter less than that of the casing, the bit having no diamonds or cutters on its outer surfaces which may come into contact with the oil well or the casing walls.
2. A drilling or a coring tool according to claim 1 in combination with a stabilizer to which it is attached, the stabilizer having radially extending "wings" or "pads" with wear resistant surfaces adapted to contact the casing walls and to provide stabilization of the drill bit during drilling of the bung.
3. A drilling tool according to claim 1 or claim 2 which has radial drilling cutters which extend the full required diameter of the casing.
4. A coring cutter according to claim 1 or claim 2 adapted to cut and remove a core of the bung or packer.
5. A coring cutter according to claim 4 which is cylindrical and has within it a drill shaft which carries the pilot drill bit, a centralizing plate being slidable on the shaft and within the core cutter.
6. A core cutter according to claim 5 and in which the centralizing plate, which keeps the drill shaft running true, can slide up the shaft being pushed by the core as it is being drilled.
7. A coring cutter according to any of claims 4 to 6 and in which a core retaining ring is provided on the pilot drill bit shaft.
8. A coring cutter according to any of claims 4 to 7 and in which a core catcher is provided on the inernal surface of the coring tool or bit.
9. A drilling tool substantially as hereinbefore particularly described and as illustrated with reference to Figures 1 to 5 of the accompanying drawings.
10. A coring tool substantially as hereinbefore particularly described and as illustrated in Figure 6 of the accompanying drawings.
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
GB878713702A GB8713702D0 (en) | 1987-06-11 | 1987-06-11 | Drilling tool |
GB878715207A GB8715207D0 (en) | 1987-06-29 | 1987-06-29 | Drilling/coring tool |
Publications (2)
Publication Number | Publication Date |
---|---|
GB8812873D0 GB8812873D0 (en) | 1988-07-06 |
GB2207158A true GB2207158A (en) | 1989-01-25 |
Family
ID=26292346
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
GB08812873A Withdrawn GB2207158A (en) | 1987-06-11 | 1988-05-31 | Drilling or coring tool |
Country Status (1)
Country | Link |
---|---|
GB (1) | GB2207158A (en) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008104179A2 (en) | 2007-02-28 | 2008-09-04 | Welltec A/S | Drilling head for reborinq a stuck valve |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN115637931B (en) * | 2022-09-08 | 2023-07-21 | 中国石油化工股份有限公司勘探分公司 | Composite drilling bit and coring while drilling method |
Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB215051A (en) * | 1923-01-08 | 1924-05-08 | Richard Ford Jenkins | Improved operative tool for well-boring |
GB232522A (en) * | 1924-12-12 | 1925-04-23 | Nelson Sheridan Burton | Improvements in and relating to rotary well drills |
US3469641A (en) * | 1967-12-11 | 1969-09-30 | Cominco Ltd | Reaming bit assembly |
-
1988
- 1988-05-31 GB GB08812873A patent/GB2207158A/en not_active Withdrawn
Patent Citations (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
GB215051A (en) * | 1923-01-08 | 1924-05-08 | Richard Ford Jenkins | Improved operative tool for well-boring |
GB232522A (en) * | 1924-12-12 | 1925-04-23 | Nelson Sheridan Burton | Improvements in and relating to rotary well drills |
US3469641A (en) * | 1967-12-11 | 1969-09-30 | Cominco Ltd | Reaming bit assembly |
Cited By (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
WO2008104179A2 (en) | 2007-02-28 | 2008-09-04 | Welltec A/S | Drilling head for reborinq a stuck valve |
WO2008104179A3 (en) * | 2007-02-28 | 2008-10-16 | Weltec As | Drilling head for reborinq a stuck valve |
EP2314825A1 (en) * | 2007-02-28 | 2011-04-27 | Welltec A/S | Drilling head for reboring a stuck valve |
CN101657603B (en) * | 2007-02-28 | 2011-08-17 | 韦尔泰克公司 | Drilling head for reborinq a stuck valve |
US8042613B2 (en) | 2007-02-28 | 2011-10-25 | Weltec A/S | Drilling head for reboring a stuck valve |
CN102322220A (en) * | 2007-02-28 | 2012-01-18 | 韦尔泰克有限公司 | The drill bit that the valve member of jam is bored a hole again |
CN102322220B (en) * | 2007-02-28 | 2014-05-14 | 韦尔泰克有限公司 | Drilling head for reborinq stuck valve |
Also Published As
Publication number | Publication date |
---|---|
GB8812873D0 (en) | 1988-07-06 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US4696502A (en) | Dual string packer mill | |
US4323130A (en) | Drill bit | |
USRE32036E (en) | Drill bit | |
US4478297A (en) | Drill bit having cutting elements with heat removal cores | |
US4635738A (en) | Drill bit | |
US4096917A (en) | Earth drilling knobby bit | |
US4724913A (en) | Drill bit and improved cutting element | |
US7240731B2 (en) | Shoe for expandable liner system and method | |
US3051255A (en) | Reamer | |
AU2009246389B2 (en) | Sonic drill bit for core sampling | |
CA2206169C (en) | A bit retention device for a bit and chuck assembly of a down-the-hole percussive drill | |
US4381825A (en) | Drill bit nozzle | |
US4442909A (en) | Drill bit | |
EP0356657A2 (en) | Apparatus for taking core samples | |
MX2011006188A (en) | Method of manufacturing and repairing fixed-cutter drag-type rotary tools with cutting control structures. | |
US4655479A (en) | Pre-set torque limiter sub | |
US4324300A (en) | Rotary drill bit | |
US9580969B2 (en) | Cutting assembly suitable for use on a drillable drill bit | |
US2708104A (en) | Core drill | |
GB2207158A (en) | Drilling or coring tool | |
US4323131A (en) | Removable anti-wear insert | |
CA1203750A (en) | Oil well packer retriever | |
US2551995A (en) | Rotary core drill with jar mechanism | |
US10502001B2 (en) | Earth-boring tools carrying formation-engaging structures | |
US2021184A (en) | Drilling structure and bit |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
WAP | Application withdrawn, taken to be withdrawn or refused ** after publication under section 16(1) |