CA1087165A - Means for drilling - Google Patents
Means for drillingInfo
- Publication number
- CA1087165A CA1087165A CA301,835A CA301835A CA1087165A CA 1087165 A CA1087165 A CA 1087165A CA 301835 A CA301835 A CA 301835A CA 1087165 A CA1087165 A CA 1087165A
- Authority
- CA
- Canada
- Prior art keywords
- drilling
- casing tube
- guide body
- rearwardly
- bit
- 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.)
- Expired
Links
- 238000005553 drilling Methods 0.000 title claims abstract description 108
- 230000013011 mating Effects 0.000 claims description 4
- 238000011010 flushing procedure Methods 0.000 description 6
- 238000010276 construction Methods 0.000 description 1
- 239000000543 intermediate Substances 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 230000002093 peripheral effect Effects 0.000 description 1
- WQGWDDDVZFFDIG-UHFFFAOYSA-N pyrogallol Chemical compound OC1=CC=CC(O)=C1O WQGWDDDVZFFDIG-UHFFFAOYSA-N 0.000 description 1
- 230000002226 simultaneous effect Effects 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP 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
- E21B10/265—Bi-center drill bits, i.e. an integral bit and eccentric reamer used to simultaneously drill and underream the hole
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B10/00—Drill bits
- E21B10/36—Percussion drill bits
- E21B10/38—Percussion drill bits characterised by conduits or nozzles for drilling fluids
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B10/00—Drill bits
- E21B10/36—Percussion drill bits
- E21B10/40—Percussion drill bits with leading portion
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B10/00—Drill bits
- E21B10/64—Drill bits characterised by the whole or part thereof being insertable into or removable from the borehole without withdrawing the drilling pipe
- E21B10/66—Drill bits characterised by the whole or part thereof being insertable into or removable from the borehole without withdrawing the drilling pipe the cutting element movable through the drilling pipe and laterally shiftable
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B7/00—Special methods or apparatus for drilling
- E21B7/20—Driving or forcing casings or pipes into boreholes, e.g. sinking; Simultaneously drilling and casing boreholes
Abstract
MEANS FOR DRILLING
Abstract of the Disclosure Means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of trailing casing tube means which are passed by rotatable drill rod means, said drilling tool comprising a centrally provided bit and eccentrically disposed reamer cutting edge means in axial proximity rearwardly of said bit. A cylindrical guide body is in coaxial relation to said bit the forward portion of said guide body having a diameter chosen for sliding engagement with the interior cylindrical portion of a mouth portion of said casing tube means, said guide body having rearwardly extending slots provided in the mantle surface of its forward portion for the discharge of drilling debris rearwardly through an annular space provided between said rotatable drill rod means and said casing tube means.
Abstract of the Disclosure Means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of trailing casing tube means which are passed by rotatable drill rod means, said drilling tool comprising a centrally provided bit and eccentrically disposed reamer cutting edge means in axial proximity rearwardly of said bit. A cylindrical guide body is in coaxial relation to said bit the forward portion of said guide body having a diameter chosen for sliding engagement with the interior cylindrical portion of a mouth portion of said casing tube means, said guide body having rearwardly extending slots provided in the mantle surface of its forward portion for the discharge of drilling debris rearwardly through an annular space provided between said rotatable drill rod means and said casing tube means.
Description
7165 :
MEANS FOR DRILLING
The present invention relates to a means for drilling comprising a rotatable drilling tool adapted to drill a hole in advance of trailing casing tube means which are passed by rotatable drill rod means.
Drilling tools of the above character usually are provided in connec- ;
tion with a down-the-hole drilling machine, for in9tance where drilling a well t said drilling tool usually consisting of a centrally provided pilot bit and a rear excentrically provided reamer. The casing tube does not rotate, it follows the reamer by its own weight while the drill rod string rotates. Flushing medium is supplied to the tool through a central flusing bore provided through the casing and drill pipes.
For the di3charge of drilling debri~ rearwardly it has been proposed to maintain an annular slot of predetermined and ~ubstantially constant width between the mouth of said Casing tube means and said drilling tool as deqcribed in US Patent 3.848.683. This arrangement enables sifting the flushing medium through said slot for preventing oversized drilling particle6 to be entrained into said slot and casing tube means.
A disadvantage here is that such arrangement not permits sufficiently effective discharge of drilling debris to an amount more proportional to the amount of flushing medium that is able of being 9upplied to the drilling tool which negatively affect~ the drilling capacity.
According to the present invention there i8 proposed a new drilling means of the type incorporating a rotatable drilling tool of the above character comprising a central drill bit and eccentrioally disposed reamer cutting edge means mounted in axial proximity rearwardly of said bit, wherein the improvement comprises a cylindrical guide body disposed in coaxial relation to said bit and ` provided a~ `the inside ofsaid ca-8$ng tube and of a diameter chogen for Bliding engagement with an interiorcylindrical portion of ~aid ¢a~ing tube means, said guide body simul-taneou~ly having rearwardly extending slots provided direotly in the mantle surface thereof for the discharee of drilling debris. ~hese rearwardly extending slots should preferably be spiral-curved. It has been found in practice that such a drilling means provides an es~ential improvement regarding its capacity of removing drilling debris by flushing medium rearwardly through said oasing tube means.
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-. . . : -..:
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..
10~7165 Such a drilling means with said guide body in sliding engagement with the interior of said casing tu~e means also promotes better guiding performance of t~e drilling tool within said casing. Such a drilling tool furt~ermore represents a simplification of the previously related construction.
According to one broad aspect, the invention relates to means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of trailing casing tube means through which are passed rotatable drill rod means, said drilling tool comprising a centrally provided bit and eccentricall~ d~sposed reamer cutting edge means in axial proximity rearwardly of said bit, characterized by a cylindrical guide body and the forward portion of said guide body having a diameter chosen for sliding engagement with the interior cylindrical portion of a mouth portion of said casing tu~e means, said guide body having rearwardly e~tending slots provided in the mantle surface of ita forward portion for the discharge of drilling debris rearwardly through an annular space provided between said rotatable drill rod means and said : casing tube means.
According to another aspect, the invention relates to means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which is moved by rotatable drill rod means, said casing tube means having a forward mouth portion with a cylindrical interior surface, said drill rod means and said casing tube means having an annular space therebetween, said drilling tool comprising a central bit, an eccentrically disposed reamer cutting edge means in axial proximity rear-wardly of said ~.it, characterized by a cylindrical guide body, ~ - 2 -'~
-' ~0~716S
wherein the forward portion of said guide ~ody has such a diameter as to provide sliding engagement with the interior cylindrical surface of said mo~th portion of said casing tube means, said guide body having a plurality of rearwardly-extending recesses in the cylindrical surface of its forward portion for the discharge of drilling debris rearwardly to said annular space provided between said rotatable drill rod means and said casing tube means, said recesses being U-shaped in cross-section and the width of each said recess exceeding the radial depth thereof.
In accordance ~ith a further aspect, the invention relates to means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which are moved by rotatable drill rod means, said casing tube means having a forward mouth portion -. ~ .
with a cylindrical interior surface, said drill rod means and :~ -said casing tube means having an annular space therebetween, said drilling tool comprising a bit assembly which is centrally positioned with respect to the axis of said casing tube means, a reamer cutter presenting cutting edge means in axial proximity and rearwardly with respect to said bit assembly, a guide body attached to and supporting said bit assembly and slidably positioned in said forward mouth portion and the ad;acent portion of said casing tube means and presenting a plurality of guide surfaces mating with said interior surface of said forward mouth portion whereby said drilling tool is guided and maintained in precise axial alignment during its movement with respect to said forward mouth portion, said guide body having slot means extending axially throughout the extent of said guide surface of said cylindrical guide body and said bit assembly to said annular space to thereby provide for the ~- 2a -B
.
10~7165 discharge of drilling de~ris rear~ardly from the forward end of said forward mouth portion to said annular space, whereby said guide body provides the functions of holding said bit ~ -assembly in precise alignment during successive axial drilling ~ :
qtrokes of said bit assem~ly and drilling debris is :
forced rearwardly from said bit assembly into said annular space.
In accordance with yet another aspect, the invention relates to means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which are moved by rotatable drill rod means, said casing tube means having a forward mouth portion with a cylindrical interior surface, said drill rod means and said casing tube means having an annular space therebetween, said drilling tool comprising a central bit and an eccentrically disposed reamer cutting edge means in axial proximity rearwardly of said bit, characterized by a cylindrical guide body in coaxial relation to said bit, the forward portion of said guide body having a forward portLon of such a diameter as to provide sliding engagement with the interior cylindrical surface of said mouth portion of said casing tube means, said guide body having a portion of enlarged diameter extending rearwardly from said forward portion which is of substantially the diameter of the adjacent portion of said casing tube means, said guide body having a plurality of recesses which are U-shaped in cross-section and whic~ provide for the passage of drilling debris rearwardly from below said guide body to said annular space between said drill rod and said casing tube means, whereby said guide body provides the functions of holding said bit assembly in precise alignment during successive axial drilling strokes of said bit assembly and drilling debris is ~ - 2b -~ 716S
. . .
forced rearwardly from said bit assembly into said annular space.
In accordance with a still further aspect, the invention provides in a drilling machine of the type having a rotatable drilling tool for drilling a hole in advance of a trailing casing tube which has a cylindrical inner surface and a rotata~le drill rod assembly attached to said drilling tool, wherein said drilling tool includes a central pilot bit and an eccentric cutting bit, and wherein said casing tu~e has a cylindrical mouth portion upon its forward end which is of reduced diameter and forms an annular driving shoulder in the inner surface of said casing tube, and wherein said drilling tool has a cylindrical ~ody with a portion which is snugly --received in said mouth portion and a flange portion whic~
is adjacent thereto and which is snugly received in the casing tube, said body portion holding said drilling tool in axial alignment with said casing tube by the sliding relationship ~etween the cylindrical inner surfaces of said casing tube and said mouth portion and the mating surface portions of said body, said body having a plurality of grooves which extend axially thereof and provide passageways for t~e discharge of drilling debris rearwardly from the leading portion of said drilling tool to the annular space between said drilling tool and said casing tube.
The invention will now be descri~ed more in detail with reference to the accompanying drawings in which one embodiment of the invention is illustrated by way of example, in which:
Fig. 1 is a prior art drilling means for earth drilling, Fig. 2 is a drilling means according to the present invention, Fig. 3 is a side view of a guide mem~er used with the .~4 ~- 2c -- 1~871{~5 drill means of the invention, and Fig. 4 is an end view taken on line A-A in Fig. 3.
In the drawings, Fig. 1 shows an eccentric drill tool intended for a down-the-hole drill application, comprising a cylindrical guide member 10, an eccentric reamer 11 and a central pilot bit 12. The upper portion of the shaft of the guide is provided as a splined shank 13 and rotatably connected to the lower end portion of a drill pipe 14 that is connected to a drilling machine. The guide member 10 is located in a casing tube means 15 the lower end of which is welded at 16 to be connected with a thickened mouth portion 17 providing internally an upward annular driving shoulder 18 against which a correspondingly thickened flange 19 of said guide member 10 is intended to act so that the impacts of the down-the-hole drill can be transmitted to the casing tube means 15. The lower portion of cylindrîcal guide member 10 has a reduced diameter such as to provide a peripheral annular slot 20 between the member 10 and the thickened mouth portion 17 of the casing tube means 16. Flushing medium and drilling debris is intended to be sifted through the slot 20 into an annular groove 21 in said guide member 10 and then through a plurality of substantially axial bores 22 into an annular space 23 in the casing for elevation and removal by continued flushing. A disadvantage here is that removal of drilling debris rearwardly has too limited capacity in comparison wlth those amounts of flush~ng medium that can be submitted to the drilling tool. Especlally when drilling in mixtures of earth and mud it has been found that said axial bores 22 often become silted-up, thus resulting in more limited removal of debris.
- 2d -~ith the embodiment of the invention, illustrated in Figs. 2-4, identi-cal parts of the structure have been given same reference numerals as in Fig. 1 for reasons of clarity. Hence, the drilling means of the in-vention comprises a cylindrical guide member 10, a reamer 11 having eccentric cutting edge means and a centrally provided pilot bit 12, the arrangement being such that said reamer 11 is mounted on an inter-mediate portion of the rearwardly extending and exteriorly threaded shaft of said bit whereas said cylindrical guide member 10 is disposed on the rear end of said shaft in coaxial relation to said pilot bit 12.
The guide member also has a rearwardly extending shaft portion 13 that is splined similarly as shown in Fig. 1 so as to be rotatable by drill pipe 14. The forward portion 24 of said cylindrical guide member 10 has a diameter chosen for sliding engagement with the interior cylindri- ¦
cal portion of thickened mouth portion 17 of casing tube means 15 wel-ded together at 16. A shoulder 18 is provided interiorly of said mouth portion 17 for cooperation with a flange 19 of the guide member 10 for transmitting impacts to said casing tube means 15.
According to the invention the forward portion 24 of guide member 10 is provided with same diameter as the interior diameter of mouth por-tion 17 of said casingtube means 15 such that sliding engagement occurs therebetween. For the removal of drilling debris rearwardly extending recesses 25 are provided in the mantle surface of said forward portion 24 of the guide member 10. These recesses 25 should preferably be ~pi-rally coiled as illustrated in Figs. 2-4. ~his gives the advantage that very small particles will not have any tendency of wedgingly entraining between said guide portion 24 and said mouth portion 17, they will in-stead effectively be brought rearwardly by the walls of said ~piral curved recesses 25 during rotation of the drillin~ tool. These re~e~ees should extend axially along the whole forwa~U~ ion of said guide member 10, i.e. along portion 24 as well as axially through said flange 19. Further, said recesses should be evenly distributed around the circumference of said guide member 10, for instanoe diametrally opposed as shown in Fig. 4. ~his gives the advantage of eliminating any problem with the location of the entrance of the exterior thread of the shaft of the bit 12 relative to the location of said reces~es when entering said threaded bit shaft into its threaded bore 26 in the guide member 10.
~:, '.
r~~ 4 ln~ 6s ~he recesses 25 should suitably be U-shaped in cross section and the width should exceed the radial depth thereof. Provision of externally provided recesses on the mantle surface of said guide member, as alter-native to the prior art solution di~closed in Fig. 1, has shown to give clear improvement~ to the drilling capacity under various condi-tion~, It should be understood that this embodiment of the invention is only illustrative of the invention and that various modifications thereof may be made within the sco~e of the claims following hereinafter.
, .
" :
MEANS FOR DRILLING
The present invention relates to a means for drilling comprising a rotatable drilling tool adapted to drill a hole in advance of trailing casing tube means which are passed by rotatable drill rod means.
Drilling tools of the above character usually are provided in connec- ;
tion with a down-the-hole drilling machine, for in9tance where drilling a well t said drilling tool usually consisting of a centrally provided pilot bit and a rear excentrically provided reamer. The casing tube does not rotate, it follows the reamer by its own weight while the drill rod string rotates. Flushing medium is supplied to the tool through a central flusing bore provided through the casing and drill pipes.
For the di3charge of drilling debri~ rearwardly it has been proposed to maintain an annular slot of predetermined and ~ubstantially constant width between the mouth of said Casing tube means and said drilling tool as deqcribed in US Patent 3.848.683. This arrangement enables sifting the flushing medium through said slot for preventing oversized drilling particle6 to be entrained into said slot and casing tube means.
A disadvantage here is that such arrangement not permits sufficiently effective discharge of drilling debris to an amount more proportional to the amount of flushing medium that is able of being 9upplied to the drilling tool which negatively affect~ the drilling capacity.
According to the present invention there i8 proposed a new drilling means of the type incorporating a rotatable drilling tool of the above character comprising a central drill bit and eccentrioally disposed reamer cutting edge means mounted in axial proximity rearwardly of said bit, wherein the improvement comprises a cylindrical guide body disposed in coaxial relation to said bit and ` provided a~ `the inside ofsaid ca-8$ng tube and of a diameter chogen for Bliding engagement with an interiorcylindrical portion of ~aid ¢a~ing tube means, said guide body simul-taneou~ly having rearwardly extending slots provided direotly in the mantle surface thereof for the discharee of drilling debris. ~hese rearwardly extending slots should preferably be spiral-curved. It has been found in practice that such a drilling means provides an es~ential improvement regarding its capacity of removing drilling debris by flushing medium rearwardly through said oasing tube means.
- . . . /~
- -: . . . . . - -: : . -. . . :
. . : .:, . . .
-. . . : -..:
. -.
..
10~7165 Such a drilling means with said guide body in sliding engagement with the interior of said casing tu~e means also promotes better guiding performance of t~e drilling tool within said casing. Such a drilling tool furt~ermore represents a simplification of the previously related construction.
According to one broad aspect, the invention relates to means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of trailing casing tube means through which are passed rotatable drill rod means, said drilling tool comprising a centrally provided bit and eccentricall~ d~sposed reamer cutting edge means in axial proximity rearwardly of said bit, characterized by a cylindrical guide body and the forward portion of said guide body having a diameter chosen for sliding engagement with the interior cylindrical portion of a mouth portion of said casing tu~e means, said guide body having rearwardly e~tending slots provided in the mantle surface of ita forward portion for the discharge of drilling debris rearwardly through an annular space provided between said rotatable drill rod means and said : casing tube means.
According to another aspect, the invention relates to means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which is moved by rotatable drill rod means, said casing tube means having a forward mouth portion with a cylindrical interior surface, said drill rod means and said casing tube means having an annular space therebetween, said drilling tool comprising a central bit, an eccentrically disposed reamer cutting edge means in axial proximity rear-wardly of said ~.it, characterized by a cylindrical guide body, ~ - 2 -'~
-' ~0~716S
wherein the forward portion of said guide ~ody has such a diameter as to provide sliding engagement with the interior cylindrical surface of said mo~th portion of said casing tube means, said guide body having a plurality of rearwardly-extending recesses in the cylindrical surface of its forward portion for the discharge of drilling debris rearwardly to said annular space provided between said rotatable drill rod means and said casing tube means, said recesses being U-shaped in cross-section and the width of each said recess exceeding the radial depth thereof.
In accordance ~ith a further aspect, the invention relates to means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which are moved by rotatable drill rod means, said casing tube means having a forward mouth portion -. ~ .
with a cylindrical interior surface, said drill rod means and :~ -said casing tube means having an annular space therebetween, said drilling tool comprising a bit assembly which is centrally positioned with respect to the axis of said casing tube means, a reamer cutter presenting cutting edge means in axial proximity and rearwardly with respect to said bit assembly, a guide body attached to and supporting said bit assembly and slidably positioned in said forward mouth portion and the ad;acent portion of said casing tube means and presenting a plurality of guide surfaces mating with said interior surface of said forward mouth portion whereby said drilling tool is guided and maintained in precise axial alignment during its movement with respect to said forward mouth portion, said guide body having slot means extending axially throughout the extent of said guide surface of said cylindrical guide body and said bit assembly to said annular space to thereby provide for the ~- 2a -B
.
10~7165 discharge of drilling de~ris rear~ardly from the forward end of said forward mouth portion to said annular space, whereby said guide body provides the functions of holding said bit ~ -assembly in precise alignment during successive axial drilling ~ :
qtrokes of said bit assem~ly and drilling debris is :
forced rearwardly from said bit assembly into said annular space.
In accordance with yet another aspect, the invention relates to means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which are moved by rotatable drill rod means, said casing tube means having a forward mouth portion with a cylindrical interior surface, said drill rod means and said casing tube means having an annular space therebetween, said drilling tool comprising a central bit and an eccentrically disposed reamer cutting edge means in axial proximity rearwardly of said bit, characterized by a cylindrical guide body in coaxial relation to said bit, the forward portion of said guide body having a forward portLon of such a diameter as to provide sliding engagement with the interior cylindrical surface of said mouth portion of said casing tube means, said guide body having a portion of enlarged diameter extending rearwardly from said forward portion which is of substantially the diameter of the adjacent portion of said casing tube means, said guide body having a plurality of recesses which are U-shaped in cross-section and whic~ provide for the passage of drilling debris rearwardly from below said guide body to said annular space between said drill rod and said casing tube means, whereby said guide body provides the functions of holding said bit assembly in precise alignment during successive axial drilling strokes of said bit assembly and drilling debris is ~ - 2b -~ 716S
. . .
forced rearwardly from said bit assembly into said annular space.
In accordance with a still further aspect, the invention provides in a drilling machine of the type having a rotatable drilling tool for drilling a hole in advance of a trailing casing tube which has a cylindrical inner surface and a rotata~le drill rod assembly attached to said drilling tool, wherein said drilling tool includes a central pilot bit and an eccentric cutting bit, and wherein said casing tu~e has a cylindrical mouth portion upon its forward end which is of reduced diameter and forms an annular driving shoulder in the inner surface of said casing tube, and wherein said drilling tool has a cylindrical ~ody with a portion which is snugly --received in said mouth portion and a flange portion whic~
is adjacent thereto and which is snugly received in the casing tube, said body portion holding said drilling tool in axial alignment with said casing tube by the sliding relationship ~etween the cylindrical inner surfaces of said casing tube and said mouth portion and the mating surface portions of said body, said body having a plurality of grooves which extend axially thereof and provide passageways for t~e discharge of drilling debris rearwardly from the leading portion of said drilling tool to the annular space between said drilling tool and said casing tube.
The invention will now be descri~ed more in detail with reference to the accompanying drawings in which one embodiment of the invention is illustrated by way of example, in which:
Fig. 1 is a prior art drilling means for earth drilling, Fig. 2 is a drilling means according to the present invention, Fig. 3 is a side view of a guide mem~er used with the .~4 ~- 2c -- 1~871{~5 drill means of the invention, and Fig. 4 is an end view taken on line A-A in Fig. 3.
In the drawings, Fig. 1 shows an eccentric drill tool intended for a down-the-hole drill application, comprising a cylindrical guide member 10, an eccentric reamer 11 and a central pilot bit 12. The upper portion of the shaft of the guide is provided as a splined shank 13 and rotatably connected to the lower end portion of a drill pipe 14 that is connected to a drilling machine. The guide member 10 is located in a casing tube means 15 the lower end of which is welded at 16 to be connected with a thickened mouth portion 17 providing internally an upward annular driving shoulder 18 against which a correspondingly thickened flange 19 of said guide member 10 is intended to act so that the impacts of the down-the-hole drill can be transmitted to the casing tube means 15. The lower portion of cylindrîcal guide member 10 has a reduced diameter such as to provide a peripheral annular slot 20 between the member 10 and the thickened mouth portion 17 of the casing tube means 16. Flushing medium and drilling debris is intended to be sifted through the slot 20 into an annular groove 21 in said guide member 10 and then through a plurality of substantially axial bores 22 into an annular space 23 in the casing for elevation and removal by continued flushing. A disadvantage here is that removal of drilling debris rearwardly has too limited capacity in comparison wlth those amounts of flush~ng medium that can be submitted to the drilling tool. Especlally when drilling in mixtures of earth and mud it has been found that said axial bores 22 often become silted-up, thus resulting in more limited removal of debris.
- 2d -~ith the embodiment of the invention, illustrated in Figs. 2-4, identi-cal parts of the structure have been given same reference numerals as in Fig. 1 for reasons of clarity. Hence, the drilling means of the in-vention comprises a cylindrical guide member 10, a reamer 11 having eccentric cutting edge means and a centrally provided pilot bit 12, the arrangement being such that said reamer 11 is mounted on an inter-mediate portion of the rearwardly extending and exteriorly threaded shaft of said bit whereas said cylindrical guide member 10 is disposed on the rear end of said shaft in coaxial relation to said pilot bit 12.
The guide member also has a rearwardly extending shaft portion 13 that is splined similarly as shown in Fig. 1 so as to be rotatable by drill pipe 14. The forward portion 24 of said cylindrical guide member 10 has a diameter chosen for sliding engagement with the interior cylindri- ¦
cal portion of thickened mouth portion 17 of casing tube means 15 wel-ded together at 16. A shoulder 18 is provided interiorly of said mouth portion 17 for cooperation with a flange 19 of the guide member 10 for transmitting impacts to said casing tube means 15.
According to the invention the forward portion 24 of guide member 10 is provided with same diameter as the interior diameter of mouth por-tion 17 of said casingtube means 15 such that sliding engagement occurs therebetween. For the removal of drilling debris rearwardly extending recesses 25 are provided in the mantle surface of said forward portion 24 of the guide member 10. These recesses 25 should preferably be ~pi-rally coiled as illustrated in Figs. 2-4. ~his gives the advantage that very small particles will not have any tendency of wedgingly entraining between said guide portion 24 and said mouth portion 17, they will in-stead effectively be brought rearwardly by the walls of said ~piral curved recesses 25 during rotation of the drillin~ tool. These re~e~ees should extend axially along the whole forwa~U~ ion of said guide member 10, i.e. along portion 24 as well as axially through said flange 19. Further, said recesses should be evenly distributed around the circumference of said guide member 10, for instanoe diametrally opposed as shown in Fig. 4. ~his gives the advantage of eliminating any problem with the location of the entrance of the exterior thread of the shaft of the bit 12 relative to the location of said reces~es when entering said threaded bit shaft into its threaded bore 26 in the guide member 10.
~:, '.
r~~ 4 ln~ 6s ~he recesses 25 should suitably be U-shaped in cross section and the width should exceed the radial depth thereof. Provision of externally provided recesses on the mantle surface of said guide member, as alter-native to the prior art solution di~closed in Fig. 1, has shown to give clear improvement~ to the drilling capacity under various condi-tion~, It should be understood that this embodiment of the invention is only illustrative of the invention and that various modifications thereof may be made within the sco~e of the claims following hereinafter.
, .
" :
Claims (11)
PROPERTY OR PRIVILEGE IS CLAIMED ARE DEFINED AS FOLLOWS:
1. Means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of trailing casing tube means through which are passed rotatable drill rod means, said drilling tool comprising a centrally provided bit and eccentrically disposed reamer cutting edge means in axial proximity rearwardly of said bit, characterized by a cylindrical guide body and the forward portion of said guide body having a diameter chosen for sliding engagement with the interior cylindrical portion of a mouth portion of said casing tube means, said guide body having rearwardly extending slots provided in the mantle surface of its forward portion for the discharge of drilling debris rearwardly through an annular space provided between said rotatable drill rod means and said casing tube means.
2. Means for drilling as defined in claim 1, characterized in that said rearwardly extending slots provided on said guide body are spiral coiled.
3. Means for drilling as defined in claim 1 or 2, wherein said drilling tool and said guide body are connected to a rotatable drill tube associated with a down-the-hole drilling machine and said casing tube means having at its lower end a thickened mouth portion providing an upward annular driving shoulder for cooperation with a flange on said guide body for transmitting impacts to said casing tube means, characterized in that said guide body is provided with rearwardly extending recesses extending along said forward portion of said guide body and also passing axially through said flange on said guide member.
4. Means for drilling as defined in claim 1, characterized in that said rearwardly extending recesses are evenly distributed around the periphery of said guide body.
5. Means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which is moved by rotatable drill rod means, said casing tube means having a forward mouth portion with a cylindrical interior surface, said drill rod means and said casing tube means having an annular space therebetween, said drilling tool comprising a central bit, an eccentrically disposed reamer cutting edge means in axial proximity rearwardly of said bit, characterized by a cylindrical guide body, wherein the forward portion of said guide body has such a diameter as to provide sliding engagement with the interior cylindrical surface of said mouth portion of said casing tube means, said guide body having a plurality of rearwardly-extending recesses in the cylindrical surface of its forward portion for the discharge of drilling debris rearwardly to said annular space provided between said rotatable drill rod means and said casing tube means, said recesses being U-shaped in cross-section and the width of each said recess exceeding the radial depth thereof.
6. Means for drilling as defined in claim 5, wherein said drilling tool and said guide body are connected to a rotatable drill tube associated with a down-the-hole drilling machine and said casing tube means having at its lower end a thickened mouth portion providing an upward annular driving shoulder for cooperation with a flange on said guide body for transmitting impacts to said casing tube, means characterized in that said rearwardly-extending recesses extend along said forward portion of said guide body and also pass axially through said flange on said guide member.
7. Means as described in claim 5 wherein said recesses are of uniform depth.
8. Means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which are moved by rotatable drill rod means, said casing tube means having a forward mouth portion with a cylindrical interior surface, said drill rod means and said casing tube means having an annular space therebetween, said drilling tool comprising a bit assembly which is centrally positioned with respect to the axis of said casing tube means, a reamer cutter presenting cutting edge means in axial proximity and rearwardly with respect to said bit assembly, a guide body attached to and supporting said bit assembly and slidably positioned in said forward mouth portion and the adjacent portion of said casing tube means and presenting a plurality of guide surfaces mating with said interior surface of said forward mouth portion whereby said drilling tool is guided and maintained in precise axial alignment during its movement with respect to said forward mouth portion, said guide body having slot means extending axially throughout the extent of said guide surface of said cylindrical guide body and said bit assembly to said annular space to thereby provide for the discharge of drilling debris rearwardly from the forward end of said forward mouth portion to said annular space, whereby said guide body provides the functions of holding said bit assembly in precise alignment during successive axial drilling strokes of said bit assembly and drilling debris is forced rearwardly from said bit assembly into said annular space.
9. Means for drilling as defined in claim 8 wherein said slot means includes recesses which are U-shaped and are separated from each other by surfaces which are in cylindrical alignment with and mate with the interior surface of said casing tube means rearwardly of said forward mouth portion.
10. Means for drilling of the type comprising a rotatable drilling tool adapted to drill a hole in advance of a trailing casing tube means which are moved by rotatable drill rod means, said casing tube means having a forward mouth portion with a cylindrical interior surface, said drill rod means and said casing tube means having an annular space therebetween, said drilling tool comprising a central bit and an eccentrically disposed reamer cutting edge means in axial proximity rearwardly of said bit, characterized by a cylindrical guide body in coaxial relation to said bit, the forward portion of said guide body having a forward portion of such a diameter as to provide sliding engagement with the interior cylindrical surface of said mouth portion of said casing tube means, said guide body having a portion of enlarged diameter extending rearwardly from said forward portion which is of substantially the diameter of the adjacent portion of said casing tube means, said guide body having a plurality of recesses which are U-shaped in cross-section and which provide for the passage of drilling debris rearwardly from below said guide body to said annular space between said drill rod and said casing tube means, whereby said guide body provides the functions of holding said bit assembly in precise alignment during successive axial drilling strokes of said bit assembly and drilling debris is forced rearwardly from said bit assembly into said annular space.
11. In a drilling machine of the type having a rotatable drilling tool for drilling a hole in advance of a trailing casing tube which has a cylindrical inner surface and a rotatable drill rod assembly attached to said drilling tool, wherein said drilling tool includes a central pilot bit and an eccentric cutting bit, and wherein said casing tube has a cylindrical mouth portion upon its forward end which is of reduced diameter and forms an annular driving shoulder in the inner surface of said casing tube, and wherein said drilling tool has a cylindrical body with a portion which is snugly received in said mouth portion and a flange portion which is adjacent thereto and which is snugly received in the casing tube, said body portion holding said drilling tool in axial alignment with said casing tube by the sliding relationship between the cylindrical inner surfaces of said casing tube and said mouth portion and the mating surface portions of said body, said body having a plurality of grooves which extend axially thereof and provide passageways for the discharge of drilling debris rearwardly from the leading portion of said drilling tool to the annular space between said drilling tool and said casing tube.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| SE7704972-4 | 1977-04-29 | ||
| SE7704972A SE411139B (en) | 1977-04-29 | 1977-04-29 | DRILLING DEVICE |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CA1087165A true CA1087165A (en) | 1980-10-07 |
Family
ID=20331165
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CA301,835A Expired CA1087165A (en) | 1977-04-29 | 1978-04-24 | Means for drilling |
Country Status (11)
| Country | Link |
|---|---|
| US (2) | US4408669A (en) |
| AT (1) | AT373359B (en) |
| AU (1) | AU516298B2 (en) |
| CA (1) | CA1087165A (en) |
| CH (1) | CH630995A5 (en) |
| DE (1) | DE2818936C3 (en) |
| FR (1) | FR2388981A1 (en) |
| GB (1) | GB1579093A (en) |
| IE (1) | IE46812B1 (en) |
| IN (1) | IN149904B (en) |
| SE (1) | SE411139B (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4793425A (en) * | 1985-06-26 | 1988-12-27 | White Kenneth M | Profiled body roller-reamer stabilizer |
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| SE454196C (en) * | 1983-09-23 | 1991-10-24 | Jan Persson | EARTH AND MOUNTAIN DRILLING DEVICE CONCERNING BORING AND LINING OF THE DRILL |
| DE8509145U1 (en) * | 1985-03-27 | 1985-05-15 | Ing. Günter Klemm, Spezialunternehmen für Bohrtechnik, 5962 Drolshagen | Drilling device |
| SE460141B (en) * | 1986-02-24 | 1989-09-11 | Santrade Ltd | DRILLING TOOL FOR ROTATION AND / OR SHIPPING DRILLING INCLUDING AN Eccentric Rifle AND RIDER INCLUDED IN SUCH A DRILLING TOOL |
| DE3620389A1 (en) * | 1986-04-15 | 1987-10-22 | Karl Eischeid | Drill |
| GB2216926B (en) * | 1988-04-06 | 1992-08-12 | Jumblefierce Limited | Drilling method and apparatus |
| SE8901200L (en) * | 1989-04-05 | 1990-10-06 | Uniroc Ab | DEVICE FOR FLUSHING A DRILL |
| SE501988C2 (en) * | 1989-04-05 | 1995-07-10 | Uniroc Ab | Drilling tools for drilling in soil and covered rock |
| SE8901199L (en) * | 1989-04-05 | 1990-10-06 | Uniroc Ab | Eccentric drill bit |
| US4962822A (en) * | 1989-12-15 | 1990-10-16 | Numa Tool Company | Downhole drill bit and bit coupling |
| DE4000691A1 (en) * | 1990-01-12 | 1991-07-18 | Fritz Zimmermann Masch U Appar | Eccentric deep hammer drill - consists of asymmetrical casing for eccentric drill activated by piston |
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| US5074366A (en) * | 1990-06-21 | 1991-12-24 | Baker Hughes Incorporated | Method and apparatus for horizontal drilling |
| US5009271A (en) * | 1990-07-16 | 1991-04-23 | Milan Maric | Drill assembly |
| SE9200563L (en) * | 1992-02-25 | 1993-07-26 | Oesten Edman | SETTING TO EXERCISE DRILLING IN EARTH STORES AND SHOOTING BEFORE SETTING |
| DE9308444U1 (en) * | 1993-06-05 | 1993-08-19 | Bilfinger Berger Bau | Drill bit for drilling in drilling ground with pressurized water |
| US5456326A (en) * | 1994-04-18 | 1995-10-10 | Exxon Production Research Company | Apparatus and method for installing open-ended tubular members axially into the earth |
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| US5992548A (en) * | 1995-08-15 | 1999-11-30 | Diamond Products International, Inc. | Bi-center bit with oppositely disposed cutting surfaces |
| US6106200A (en) * | 1996-11-12 | 2000-08-22 | Techmo Entwicklungs-Und Vertriebs Gmbh | Process and device for simultaneously drilling and lining a hole |
| AT407895B (en) * | 1996-11-12 | 2001-07-25 | Techmo Entw & Vertriebs Gmbh | Method and device for drilling and lining bore holes |
| US6536520B1 (en) | 2000-04-17 | 2003-03-25 | Weatherford/Lamb, Inc. | Top drive casing system |
| SE514113C2 (en) * | 1998-03-23 | 2001-01-08 | Sandvik Ab | Rock drilling tools for striking drilling and holders designed to be included in the tool |
| US6112835A (en) * | 1998-07-23 | 2000-09-05 | Sandvik Ab | Drilling apparatus having a radially displaceable reamer |
| US6857487B2 (en) | 2002-12-30 | 2005-02-22 | Weatherford/Lamb, Inc. | Drilling with concentric strings of casing |
| US6854533B2 (en) | 2002-12-20 | 2005-02-15 | Weatherford/Lamb, Inc. | Apparatus and method for drilling with casing |
| US6394200B1 (en) | 1999-10-28 | 2002-05-28 | Camco International (U.K.) Limited | Drillout bi-center bit |
| DE60100727T2 (en) | 2000-08-21 | 2004-07-22 | Camco International (Uk) Ltd., Stonehouse | Multi-directional cutting elements for bi-central drilling tools for drilling a casing shoe |
| US6899186B2 (en) | 2002-12-13 | 2005-05-31 | Weatherford/Lamb, Inc. | Apparatus and method of drilling with casing |
| US7730965B2 (en) | 2002-12-13 | 2010-06-08 | Weatherford/Lamb, Inc. | Retractable joint and cementing shoe for use in completing a wellbore |
| US7938201B2 (en) | 2002-12-13 | 2011-05-10 | Weatherford/Lamb, Inc. | Deep water drilling with casing |
| USRE42877E1 (en) | 2003-02-07 | 2011-11-01 | Weatherford/Lamb, Inc. | Methods and apparatus for wellbore construction and completion |
| US6926099B2 (en) * | 2003-03-26 | 2005-08-09 | Varel International, L.P. | Drill out bi-center bit and method for using same |
| US7650944B1 (en) | 2003-07-11 | 2010-01-26 | Weatherford/Lamb, Inc. | Vessel for well intervention |
| WO2007134255A2 (en) | 2006-05-12 | 2007-11-22 | Weatherford/Lamb, Inc. | Stage cementing methods used in casing while drilling |
| US8276689B2 (en) | 2006-05-22 | 2012-10-02 | Weatherford/Lamb, Inc. | Methods and apparatus for drilling with casing |
| CA2724677A1 (en) * | 2007-05-25 | 2008-12-04 | Byung Wa Yoon | Hammer bit |
| US8960329B2 (en) * | 2008-07-11 | 2015-02-24 | Schlumberger Technology Corporation | Steerable piloted drill bit, drill system, and method of drilling curved boreholes |
| WO2011079339A2 (en) * | 2009-12-23 | 2011-07-07 | Dywidag-Systems International Gmbh | Drill bit for the drilling, in particular percussion drilling or rotary percussion drilling, of holes in soil material or rock material |
| AT511616B1 (en) | 2011-09-08 | 2013-01-15 | Tmt Bbg Res And Dev Gmbh | DEVICE FOR SUPPLYING DISHWASHER IN A DRILLING HAMMER |
| US10538983B2 (en) * | 2014-08-06 | 2020-01-21 | Schlumberger Technology Corporation | Milling tools with a secondary attrition system |
| CN114109277A (en) * | 2020-08-31 | 2022-03-01 | 中国石油化工股份有限公司 | Self-adaptive rotary guide shoe |
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| US2163932A (en) * | 1937-12-06 | 1939-06-27 | Estelle B Kleaver | Casing protector |
| US2250671A (en) * | 1940-04-30 | 1941-07-29 | Joy Mfg Co | Drilling apparatus |
| US2485826A (en) * | 1948-04-19 | 1949-10-25 | Peter J Harinck | Well drilling means |
| DE1188014B (en) * | 1962-07-09 | 1965-03-04 | Atlas Copco Ab | Rock drill with eccentric drilling tool |
| FR1357144A (en) * | 1963-02-28 | 1964-04-03 | Skanska Cementgjuteriet Ab | Advanced training in eccentric trephine drills |
| AT262190B (en) * | 1964-08-11 | 1968-06-10 | Stabilator Ab | Method of knocking down the drill bit of a drill bit and drill bit |
| US3420323A (en) * | 1967-02-23 | 1969-01-07 | Land & Marine Rental Co | Drill stabilizer tool |
| US3416616A (en) * | 1967-03-01 | 1968-12-17 | Skanska Cementgjuteriet Ab | Deep drills with eccentric bits |
| FR1562342A (en) * | 1968-03-15 | 1969-04-04 | ||
| US3560060A (en) * | 1968-12-18 | 1971-02-02 | Nate Morris | Rod guide and centralizer |
| DE1927672C3 (en) * | 1969-05-30 | 1974-04-25 | Ing. Guenter Klemm Spezialunternehmen Fuer Bohrtechnik, 5962 Drolshagen | Device for overlay drilling |
| BE750586A (en) * | 1969-05-30 | 1970-11-03 | Klemm Bohrtech | DRILLING MACHINE FOR COVERING GROUNDS, CALLED "WAGON-DRILL" AND METHOD FOR ITS USE |
| US3734214A (en) * | 1971-09-24 | 1973-05-22 | Pengo Corp | Head for horizontal boring |
| US3825083A (en) * | 1972-02-02 | 1974-07-23 | Christensen Diamond Prod Co | Drill bit and stabilizer combination |
| BE795205A (en) * | 1972-02-10 | 1973-05-29 | Atlas Copco Ab | METHOD AND APPARATUS FOR ROTARY DRILLING |
| CA964640A (en) * | 1973-02-26 | 1975-03-18 | Luther G. Reaugh | Non-rotating sleeve stabilizer for drilling strings |
| US3870114A (en) * | 1973-07-23 | 1975-03-11 | Stabilator Ab | Drilling apparatus especially for ground drilling |
| US4091884A (en) * | 1976-11-15 | 1978-05-30 | Smith International, Inc. | Rotary air percussion bit |
-
1977
- 1977-04-29 SE SE7704972A patent/SE411139B/en not_active IP Right Cessation
-
1978
- 1978-04-14 AU AU35112/78A patent/AU516298B2/en not_active Expired
- 1978-04-18 GB GB15203/78A patent/GB1579093A/en not_active Expired
- 1978-04-24 US US05/899,170 patent/US4408669A/en not_active Expired - Lifetime
- 1978-04-24 CA CA301,835A patent/CA1087165A/en not_active Expired
- 1978-04-25 IN IN449/CAL/78A patent/IN149904B/en unknown
- 1978-04-27 CH CH459478A patent/CH630995A5/en not_active IP Right Cessation
- 1978-04-27 AT AT0304078A patent/AT373359B/en not_active IP Right Cessation
- 1978-04-28 FR FR7812632A patent/FR2388981A1/en active Granted
- 1978-04-28 IE IE855/78A patent/IE46812B1/en unknown
- 1978-04-28 DE DE2818936A patent/DE2818936C3/en not_active Expired
-
1983
- 1983-06-10 US US06/493,059 patent/US4545443A/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4793425A (en) * | 1985-06-26 | 1988-12-27 | White Kenneth M | Profiled body roller-reamer stabilizer |
Also Published As
| Publication number | Publication date |
|---|---|
| ATA304078A (en) | 1980-04-15 |
| AU516298B2 (en) | 1981-05-28 |
| IE46812B1 (en) | 1983-10-05 |
| AT373359B (en) | 1984-01-10 |
| US4545443A (en) | 1985-10-08 |
| GB1579093A (en) | 1980-11-12 |
| CH630995A5 (en) | 1982-07-15 |
| FR2388981A1 (en) | 1978-11-24 |
| DE2818936C3 (en) | 1982-10-21 |
| AU3511278A (en) | 1979-10-18 |
| FR2388981B1 (en) | 1983-06-24 |
| IE780855L (en) | 1978-10-29 |
| US4408669A (en) | 1983-10-11 |
| DE2818936A1 (en) | 1978-11-02 |
| IN149904B (en) | 1982-05-29 |
| DE2818936B2 (en) | 1980-12-04 |
| SE411139B (en) | 1979-12-03 |
| SE7704972L (en) | 1978-10-30 |
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| Date | Code | Title | Description |
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| MKEX | Expiry |