EP0015137A1 - Apparatus for directional drilling - Google Patents
Apparatus for directional drilling Download PDFInfo
- Publication number
- EP0015137A1 EP0015137A1 EP80300476A EP80300476A EP0015137A1 EP 0015137 A1 EP0015137 A1 EP 0015137A1 EP 80300476 A EP80300476 A EP 80300476A EP 80300476 A EP80300476 A EP 80300476A EP 0015137 A1 EP0015137 A1 EP 0015137A1
- Authority
- EP
- European Patent Office
- Prior art keywords
- borehole
- deflection member
- housing
- drilling
- deflection
- 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.)
- Granted
Links
- 238000005553 drilling Methods 0.000 title claims abstract description 34
- 229910052500 inorganic mineral Inorganic materials 0.000 claims abstract description 19
- 239000011707 mineral Substances 0.000 claims abstract description 19
- 238000000034 method Methods 0.000 claims abstract description 12
- 238000013459 approach Methods 0.000 claims 2
- 239000003245 coal Substances 0.000 description 14
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 6
- 238000007872 degassing Methods 0.000 description 4
- 238000005065 mining Methods 0.000 description 4
- 239000012530 fluid Substances 0.000 description 3
- 239000000523 sample Substances 0.000 description 3
- 230000015572 biosynthetic process Effects 0.000 description 2
- 230000009467 reduction Effects 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
- E21B7/00—Special methods or apparatus for drilling
- E21B7/04—Directional drilling
- E21B7/06—Deflecting the direction of boreholes
- E21B7/068—Deflecting the direction of boreholes drilled by a down-hole drilling motor
Definitions
- This invention relates to a method and apparatus for drilling generally horizontal boreholes in a subterranean earth formation, and more particularly to a method and apparatus for adjusting the trajectory of such a borehole to maintain same within the upper and lower boundaries of a mineral bed such as a seam of coal.
- the drilling of long generally horizontal gas drainage holes in coal beds is known in the art as a method for degasifying a coal bed in advance of mining.
- the gas drainage holes drilled in this manner are either vented or connected to a vacuum source to remove methane from a coal bed.
- the greatest problem encountered in drilling these gas relief holes is that of maintaining the bit trajectory within the coal seam such that the resulting holes are actually through the coal seam rather than through an overlying or underlying formation. Control of borehole trajectory is also important in exploratory drilling for coal or other minerals.
- a directional drilling system including a drill shaft, a down-hole fluid motor connected to a rotatable bit, and a deflection means is described in U.S. Patent No. 3,260,318.
- the deflection means described therein is a shaft housing having a slight angle formed therein to divert the drill bit from the axis of the drill shaft. Rotation of the drill shaft and housing through part of a turn changes the direction of the borehole relative to the drill shaft.
- this apparatus has been found to give poor results in controlling the trajectory of generally horizontal boreholes.
- the present invention provides drilling apparatus comprising a down-hole motof a rotatable shaft for connecting said motor to a drill bit, a non-rotating housing extending from said motor over said shaft, and a deflection member carried by said housing, said deflection member extending radially beyond said housing at one side thereof sufficiently to apply a deflection force to the wall of a borehole during drilling.
- the deflection member applies a predetermined radial force to a drill bit, causing the trajectory of the borehole being drilled to be deflected in the direction of the applied force.
- the invention provides a method of drilling a substantially horizontal borehole through a subterranean mineral bed with a drilling apparatus having a down-hole motor which provides rotation to a drill bit, wherein:
- Figure 1 shows a drill shaft 10 connected to an orienting sub 11 and a down-hole motor 12.
- Motor 12 is preferably a Moyno type fluid motor having a rotatable shaft (not shown) extending through a shaft housing 14 and connected to drill bit 13.
- Shaft housing 14 extends between motor 12 and bit 13.
- a deflection member 15 is mounted over a section of shaft housing 14, and extends radially beyond shaft housing 14 at one side. The portion of the deflection member extending beyond the shaft housing includes a wall contacting surface 26 which contacts the wall of borehole 16 being drilled through a mineral bed.
- the drilling apparatus including the drill shaft orienting sub, motor, shaft housing and drill bit is preferably of the type generally described in U.S. Patent No. 3,260,318. This type of drilling apparatus, without the deflection member of this invention, has been widely used in the drilling industry.
- Shaft housing 14 is machined to provide a reduced section including a top surface 17, sides 18 and 19, and bottom surface 20.
- Shaft housing 14 includes an internal bore 29 through which a rotatable shaft (not shown) connecting the fluid motor and the rotating drill bit extends.
- the main body element 21 of deflection member 15 is formed to fit closely over sides 18 and 19 of the reduced section of shaft housing 14 and to be slidable with respect thereto.
- Recesses 22 and 23 in main body element 21 are provided for containing springs 24 and 25 which urge borehole wall-contacting surface 26 of deflection member 15 radially outward from shaft housing 14.
- Bottom body element 27 attaches to main body element 21 with fasteners 28 to encompass the reduced section of shaft housing 14 and to compress springs 24 and 25.
- the deflection force provided by the springs depends to some extent on the particular drilling appparatus and the rate of direction change desired.
- a deflection force of at least 225 newtons is preferred.
- a deflection force of 450 to 900 newtons is generally adequate.
- Figures 3 and 4 show the assembled deflection member.
- the springs 24 and 25 act to position the deflection member so that bottom body element 27 abuts the bottom surface 20 of housing 14, and wall contacting surface 26 extends outwardly beyond the shaft housing 14 sufficiently to apply the desired deflection force to the wall of a borehole during drilling..
- the apparatus described above is particularly suited for drilling generally horizontal degasification holes in underground coal seams to reduce the methane concentration in a mine working area in advance of mining the seam.
- the degasification holes must be kept within the boundaries of the coal seam.
- the deflection member, properly used, enables an operator to maintain the borehole between the upper and lower boundaries of the coal seam.
- the drilling apparatus is set up, and after drilling an initial surface hole a short distance into the seam, the apparatus as shown in Figure 1 is inserted in the borehole and oriented with the wall-contacting surface 26 of the deflection member oriented against either the top or the bottom of the borehole.
- the apparatus In order to guide the drill bit successfully and contain it in the mineral bed, it is essential to know the position of the bit in relation to the roof and the floor of the mineral bed and the pitch and roll of the borehole. Borehole survey instruments which provide the required information are available.
- These instruments may be pumped down the drill shaft to a position near the motor where they are positioned by an orienting sub, and information as to the position of the borehole may be obtained.
- the survey probe is then removed, and if a change in direction of the borehole is indicated, the drill shaft is rotated through a part of a turn, thereby also rotating the deflection member the same amount, and drilling is resumed.
- the deflection member is oriented to provide either an upward or downward force to the drill bit, although in some cases a side force may be indicated.
- the drill shaft and deflection member are rotated 180. to provide a downward force to the drill bit. Drilling is resumed until the surveying probe indicates that the borehole is approaching the bottom layer of the mineral bed, at which time the drill shaft and deflection member are again rotated 180°. This procedure is repeated until the borehole extends the desired distance into the mineral bed.
- the deflection member in accordance with the invention has proven to be effective in drilling degasification holes in coal seams in advance of mining.
- Several degasification holes have been drilled through coal beds for distances greater than 300 meters, thereby providing significant reductions in methane concentrations at the time of actual mining of the coal bed.
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (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)
- Earth Drilling (AREA)
Abstract
Description
- This invention relates to a method and apparatus for drilling generally horizontal boreholes in a subterranean earth formation, and more particularly to a method and apparatus for adjusting the trajectory of such a borehole to maintain same within the upper and lower boundaries of a mineral bed such as a seam of coal.
- The drilling of long generally horizontal gas drainage holes in coal beds is known in the art as a method for degasifying a coal bed in advance of mining. The gas drainage holes drilled in this manner are either vented or connected to a vacuum source to remove methane from a coal bed. The greatest problem encountered in drilling these gas relief holes is that of maintaining the bit trajectory within the coal seam such that the resulting holes are actually through the coal seam rather than through an overlying or underlying formation. Control of borehole trajectory is also important in exploratory drilling for coal or other minerals.
- A directional drilling system including a drill shaft, a down-hole fluid motor connected to a rotatable bit, and a deflection means is described in U.S. Patent No. 3,260,318. The deflection means described therein is a shaft housing having a slight angle formed therein to divert the drill bit from the axis of the drill shaft. Rotation of the drill shaft and housing through part of a turn changes the direction of the borehole relative to the drill shaft. However this apparatus has been found to give poor results in controlling the trajectory of generally horizontal boreholes.
- Viewed from one aspect the present invention provides drilling apparatus comprising a down-hole motof a rotatable shaft for connecting said motor to a drill bit, a non-rotating housing extending from said motor over said shaft, and a deflection member carried by said housing, said deflection member extending radially beyond said housing at one side thereof sufficiently to apply a deflection force to the wall of a borehole during drilling.
- In operation the deflection member applies a predetermined radial force to a drill bit, causing the trajectory of the borehole being drilled to be deflected in the direction of the applied force.
- Viewed from another aspect the invention provides a method of drilling a substantially horizontal borehole through a subterranean mineral bed with a drilling apparatus having a down-hole motor which provides rotation to a drill bit, wherein:
- (a) a deflection member having an outwardly biased wall contacting surface is provided on said drilling apparatus between said motor and drill bit and oriented relative to said borehole;
- (b) said borehole is extended for a distance into said mineral bed while maintaining the orientation of said deflection member;
- (c) information regarding the trajectory of said borehole is obtained; and
- (d) said deflection member is rotated through part of a turn whereby upon resumption of drilling the trajectory of said borehole is modified.
- An embodiment of the invention will now be described by way of example and with reference to the accompanying drawings, in which:-
- Figure 1 is an illustration of a drilling apparatus showing the relation of a deflection member of the invention to the other parts of the apparatus;
- Figure 2 is an exploded view showing the structural details of a preferred embodiment of the deflection member;
- Figure 3 is an axial cross-sectional view of the apparatus in the region of the deflection member; and
- Figure 4 is a transverse cross-section taken along the line 4-4 of Figure 3.
- The relationship of a deflection member of this invention to the other parts of a drilling apparatus is shown generally in Figure 1.
- Figure 1 shows a
drill shaft 10 connected to an orienting sub 11 and a down-hole motor 12.Motor 12 is preferably a Moyno type fluid motor having a rotatable shaft (not shown) extending through ashaft housing 14 and connected todrill bit 13. Shafthousing 14 extends betweenmotor 12 andbit 13. Adeflection member 15 is mounted over a section ofshaft housing 14, and extends radially beyondshaft housing 14 at one side. The portion of the deflection member extending beyond the shaft housing includes awall contacting surface 26 which contacts the wall ofborehole 16 being drilled through a mineral bed. - The drilling apparatus including the drill shaft orienting sub, motor, shaft housing and drill bit is preferably of the type generally described in U.S. Patent No. 3,260,318. This type of drilling apparatus, without the deflection member of this invention, has been widely used in the drilling industry.
- The details of the preferred version of the deflection member of this invention are shown in Figures 2, 3 and 4.
-
Shaft housing 14 is machined to provide a reduced section including atop surface 17,sides bottom surface 20.Shaft housing 14 includes aninternal bore 29 through which a rotatable shaft (not shown) connecting the fluid motor and the rotating drill bit extends. Themain body element 21 ofdeflection member 15 is formed to fit closely oversides shaft housing 14 and to be slidable with respect thereto. Recesses 22 and 23 inmain body element 21 are provided for containingsprings surface 26 ofdeflection member 15 radially outward fromshaft housing 14.Bottom body element 27 attaches tomain body element 21 withfasteners 28 to encompass the reduced section ofshaft housing 14 and to compresssprings - Figures 3 and 4 show the assembled deflection member. When it is assembled and unrestrained, the
springs bottom body element 27 abuts thebottom surface 20 ofhousing 14, andwall contacting surface 26 extends outwardly beyond theshaft housing 14 sufficiently to apply the desired deflection force to the wall of a borehole during drilling.. - The apparatus described above is particularly suited for drilling generally horizontal degasification holes in underground coal seams to reduce the methane concentration in a mine working area in advance of mining the seam. To be effective, the degasification holes must be kept within the boundaries of the coal seam. The deflection member, properly used, enables an operator to maintain the borehole between the upper and lower boundaries of the coal seam.
- The method of drilling a borehole in a mineral bed using the deflection member of this invention will now be described. The drilling apparatus is set up, and after drilling an initial surface hole a short distance into the seam, the apparatus as shown in Figure 1 is inserted in the borehole and oriented with the wall-contacting
surface 26 of the deflection member oriented against either the top or the bottom of the borehole. In order to guide the drill bit successfully and contain it in the mineral bed, it is essential to know the position of the bit in relation to the roof and the floor of the mineral bed and the pitch and roll of the borehole. Borehole survey instruments which provide the required information are available. These instruments may be pumped down the drill shaft to a position near the motor where they are positioned by an orienting sub, and information as to the position of the borehole may be obtained. The survey probe is then removed, and if a change in direction of the borehole is indicated, the drill shaft is rotated through a part of a turn, thereby also rotating the deflection member the same amount, and drilling is resumed. Normally, the deflection member is oriented to provide either an upward or downward force to the drill bit, although in some cases a side force may be indicated. If the borehole is moving upward, and the surveying probe indicates that the borehole is near the top surface of the mineral bed, the drill shaft and deflection member are rotated 180. to provide a downward force to the drill bit. Drilling is resumed until the surveying probe indicates that the borehole is approaching the bottom layer of the mineral bed, at which time the drill shaft and deflection member are again rotated 180°. This procedure is repeated until the borehole extends the desired distance into the mineral bed. - The deflection member in accordance with the invention has proven to be effective in drilling degasification holes in coal seams in advance of mining. Several degasification holes have been drilled through coal beds for distances greater than 300 meters, thereby providing significant reductions in methane concentrations at the time of actual mining of the coal bed.
Claims (12)
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US1358479A | 1979-02-21 | 1979-02-21 | |
US13584 | 1987-02-11 |
Publications (2)
Publication Number | Publication Date |
---|---|
EP0015137A1 true EP0015137A1 (en) | 1980-09-03 |
EP0015137B1 EP0015137B1 (en) | 1984-02-22 |
Family
ID=21760692
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
EP80300476A Expired EP0015137B1 (en) | 1979-02-21 | 1980-02-19 | Apparatus for directional drilling |
Country Status (6)
Country | Link |
---|---|
EP (1) | EP0015137B1 (en) |
AU (1) | AU536113B2 (en) |
CA (1) | CA1122965A (en) |
DE (1) | DE3066665D1 (en) |
PL (1) | PL124814B1 (en) |
ZA (1) | ZA797051B (en) |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4471843A (en) * | 1982-04-23 | 1984-09-18 | Conoco Inc. | Method and apparatus for rotary drill guidance |
GB2306529A (en) * | 1995-10-26 | 1997-05-07 | Camco Drilling Group Ltd | Rotary drilling assembly |
WO2000034616A1 (en) * | 1998-12-09 | 2000-06-15 | Devico As | Apparatus for directional drilling |
WO2004113666A1 (en) * | 2003-06-17 | 2004-12-29 | Noble Drilling Services Inc. | Split housing for rotary steerable tool |
US7267184B2 (en) | 2003-06-17 | 2007-09-11 | Noble Drilling Services Inc. | Modular housing for a rotary steerable tool |
US7546209B2 (en) * | 2004-10-28 | 2009-06-09 | Williams Danny T | Formation dip geo-steering method |
US8875806B2 (en) | 2004-10-28 | 2014-11-04 | Danny T. Williams | Formation dip geo-steering method |
US8960326B2 (en) | 2004-10-28 | 2015-02-24 | Danny T. Williams | Formation dip geo-steering method |
US20160281431A1 (en) * | 2015-03-24 | 2016-09-29 | Baker Hughes Incorporated | Self-Adjusting Directional Drilling Apparatus and Methods for Drilling Directional Wells |
US10316638B1 (en) | 2004-10-28 | 2019-06-11 | Danny T. Williams | Formation dip geo-steering method |
US10544666B1 (en) | 2004-10-28 | 2020-01-28 | Danny T. Williams | Formation dip geo-steering method |
US11193331B2 (en) | 2019-06-12 | 2021-12-07 | Baker Hughes Oilfield Operations Llc | Self initiating bend motor for coil tubing drilling |
Families Citing this family (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
BE1003327A4 (en) * | 1990-01-15 | 1992-02-25 | Smet Marc Jozef Maria | STEERABLE BOTTOM DRILLS. |
Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2316409A (en) * | 1941-12-05 | 1943-04-13 | Lloyd R Downing | Oil well straightener |
US3062303A (en) * | 1960-03-21 | 1962-11-06 | Shell Oil Co | Method and apparatus for controlling hole direction and inclination |
US3098534A (en) * | 1960-06-14 | 1963-07-23 | Carr Warren Farrell | Directional drill with hydraulically extended shoe |
US3298449A (en) * | 1963-10-24 | 1967-01-17 | Drilco Oil Tools Inc | Well bore apparatus |
US3561549A (en) * | 1968-06-07 | 1971-02-09 | Smith Ind International Inc | Slant drilling tools for oil wells |
US3593810A (en) * | 1969-10-13 | 1971-07-20 | Schlumberger Technology Corp | Methods and apparatus for directional drilling |
US3888319A (en) * | 1973-11-26 | 1975-06-10 | Continental Oil Co | Control system for a drilling apparatus |
US4040495A (en) * | 1975-12-22 | 1977-08-09 | Smith International, Inc. | Drilling apparatus |
US4046204A (en) * | 1975-11-25 | 1977-09-06 | Agency Of Industrial Science & Technology | Controlled directional drilling tool |
-
1979
- 1979-12-24 AU AU54184/79A patent/AU536113B2/en not_active Ceased
- 1979-12-28 ZA ZA00797051A patent/ZA797051B/en unknown
-
1980
- 1980-01-16 CA CA343,775A patent/CA1122965A/en not_active Expired
- 1980-02-19 DE DE8080300476T patent/DE3066665D1/en not_active Expired
- 1980-02-19 EP EP80300476A patent/EP0015137B1/en not_active Expired
- 1980-02-21 PL PL1980222161A patent/PL124814B1/en unknown
Patent Citations (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US2316409A (en) * | 1941-12-05 | 1943-04-13 | Lloyd R Downing | Oil well straightener |
US3062303A (en) * | 1960-03-21 | 1962-11-06 | Shell Oil Co | Method and apparatus for controlling hole direction and inclination |
US3098534A (en) * | 1960-06-14 | 1963-07-23 | Carr Warren Farrell | Directional drill with hydraulically extended shoe |
US3298449A (en) * | 1963-10-24 | 1967-01-17 | Drilco Oil Tools Inc | Well bore apparatus |
US3561549A (en) * | 1968-06-07 | 1971-02-09 | Smith Ind International Inc | Slant drilling tools for oil wells |
US3593810A (en) * | 1969-10-13 | 1971-07-20 | Schlumberger Technology Corp | Methods and apparatus for directional drilling |
US3888319A (en) * | 1973-11-26 | 1975-06-10 | Continental Oil Co | Control system for a drilling apparatus |
US4046204A (en) * | 1975-11-25 | 1977-09-06 | Agency Of Industrial Science & Technology | Controlled directional drilling tool |
US4040495A (en) * | 1975-12-22 | 1977-08-09 | Smith International, Inc. | Drilling apparatus |
Cited By (22)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4471843A (en) * | 1982-04-23 | 1984-09-18 | Conoco Inc. | Method and apparatus for rotary drill guidance |
GB2306529A (en) * | 1995-10-26 | 1997-05-07 | Camco Drilling Group Ltd | Rotary drilling assembly |
US5778992A (en) * | 1995-10-26 | 1998-07-14 | Camco Drilling Group Limited Of Hycalog | Drilling assembly for drilling holes in subsurface formations |
GB2306529B (en) * | 1995-10-26 | 1999-02-10 | Camco Drilling Group Ltd | A drilling assembly for drilling holes in subsurface formations |
WO2000034616A1 (en) * | 1998-12-09 | 2000-06-15 | Devico As | Apparatus for directional drilling |
US6516900B1 (en) | 1998-12-09 | 2003-02-11 | Devico As | Apparatus for directional drilling |
WO2004113666A1 (en) * | 2003-06-17 | 2004-12-29 | Noble Drilling Services Inc. | Split housing for rotary steerable tool |
US7267184B2 (en) | 2003-06-17 | 2007-09-11 | Noble Drilling Services Inc. | Modular housing for a rotary steerable tool |
US8960326B2 (en) | 2004-10-28 | 2015-02-24 | Danny T. Williams | Formation dip geo-steering method |
US10544666B1 (en) | 2004-10-28 | 2020-01-28 | Danny T. Williams | Formation dip geo-steering method |
US7546209B2 (en) * | 2004-10-28 | 2009-06-09 | Williams Danny T | Formation dip geo-steering method |
US8875806B2 (en) | 2004-10-28 | 2014-11-04 | Danny T. Williams | Formation dip geo-steering method |
US9534446B2 (en) | 2004-10-28 | 2017-01-03 | Danny T. Williams | Formation dip geo-steering method |
US10119385B2 (en) | 2004-10-28 | 2018-11-06 | Danny T. Williams | Formation dip geo-steering method |
US10316638B1 (en) | 2004-10-28 | 2019-06-11 | Danny T. Williams | Formation dip geo-steering method |
US20160281431A1 (en) * | 2015-03-24 | 2016-09-29 | Baker Hughes Incorporated | Self-Adjusting Directional Drilling Apparatus and Methods for Drilling Directional Wells |
US11261667B2 (en) * | 2015-03-24 | 2022-03-01 | Baker Hughes, A Ge Company, Llc | Self-adjusting directional drilling apparatus and methods for drilling directional wells |
US11421480B2 (en) | 2015-03-24 | 2022-08-23 | Baker Hughes, A Ge Company, Llc | Drilling apparatus using a sealed self-adjusting deflection device for drilling directional wells |
US11428047B2 (en) | 2015-03-24 | 2022-08-30 | Baker Hughes, A Ge Company, Llc | Drilling assembly using a self-adjusting tilt device and sensors for drilling directional wellbores |
US11459828B2 (en) | 2015-03-24 | 2022-10-04 | Baker Hughes, LLC | Drilling apparatus using a self-adjusting deflection device and deflection sensors for drilling directional wells |
US11643877B2 (en) | 2015-03-24 | 2023-05-09 | Baker Hughes Holdings Llc | Self-adjusting directional drilling apparatus and methods for drilling directional wells |
US11193331B2 (en) | 2019-06-12 | 2021-12-07 | Baker Hughes Oilfield Operations Llc | Self initiating bend motor for coil tubing drilling |
Also Published As
Publication number | Publication date |
---|---|
ZA797051B (en) | 1980-12-31 |
AU5418479A (en) | 1980-08-28 |
CA1122965A (en) | 1982-05-04 |
PL124814B1 (en) | 1983-02-28 |
AU536113B2 (en) | 1984-04-19 |
PL222161A1 (en) | 1980-11-03 |
EP0015137B1 (en) | 1984-02-22 |
DE3066665D1 (en) | 1984-03-29 |
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