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US2134988A - Core-taking apparatus - Google Patents

Core-taking apparatus Download PDF

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Publication number
US2134988A
US2134988A US88979A US8897936A US2134988A US 2134988 A US2134988 A US 2134988A US 88979 A US88979 A US 88979A US 8897936 A US8897936 A US 8897936A US 2134988 A US2134988 A US 2134988A
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Prior art keywords
core barrel
drill stem
core
drill
sleeve
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US88979A
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John C Stokes
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Reed Roller Bit Co
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Reed Roller Bit Co
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Publication date
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Priority to US88979A priority Critical patent/US2134988A/en
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    • EFIXED CONSTRUCTIONS
    • E21EARTH OR ROCK DRILLING; MINING
    • E21BEARTH OR ROCK DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
    • E21B25/00Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors
    • E21B25/02Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors the core receiver being insertable into, or removable from, the borehole without withdrawing the drilling pipe
    • E21B25/04Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors the core receiver being insertable into, or removable from, the borehole without withdrawing the drilling pipe the core receiver having a core forming cutting edge or element, e.g. punch type core barrels

Definitions

  • Fig. 1 is a vertical cross section illustrating a core barrel latch constructed in accordance with this invention, together with a drill stem and core barrel, and the means for retrieving the core barrel;
  • Fig. 2 is a view similar to Fig. 1, but showing the lower end of the drill stem and bit with the core barrel in place therein;
  • Fig. 3 is an, elevation illustrating the spear or device for retrieving the core barrel
  • Fig. 4 is a horizontal cross section taken along the line 44 of Fig. 1.
  • the numeral 1 indicates the lower end of the lower section of drill pipe
  • the drill collar Adjacent its upper end, the drill collar is formed 5 with an internal shoulder at 5 adapted to receive a sleeve 6, this sleeve being held in place by the pin 1 on the lower end of the drill pipe I. Adjacent one side of the sleeve 6 a small groove 8 is formed for the purpose of receiving a pin 9 welded 10 into the drill collar at III, the purpose of this pin 9 being to prevent the sleeve 6 from rotating within the drill collar. I
  • this sleeve is slotted as illustrated at H for the 18 purpose of receiving'the pawl l2 which serves as the latch proper for holding the core barrel in place.
  • This pawl 12 is pivoted at l3 and springpressed by means of a spring l4 so that it is radially movable, and is, constantly urged toward its 20 innermost position.
  • the spring I4 bears within the. recess l5 formed in the wall of the drill collar opposite the sleeve 6, which recess serves to receive the shank portion l6 of the pawl l2 when the same is in its retracted or outermost position.
  • This shank portion l6 also is adapted to contact with a portion of the sleeve 6 to limit the radial inward movement of the latch portion I! of thispawl.
  • the core barrel consists of a tubular member I8 having a short sleeve-like portion l9 connected at its lower end, provided with an external shoulder adapted'to rest upon the support 2
  • the core barrel At its upper end the core barrel is provided with a fitting 23 having a chamber 24 adjacent its 40 lower end. 1
  • the passageway between this chamber 24 and the body of the core-barrel is con trolled by means of a ball valve 25 bearing against the valve seat member 26, this seat member in turn being held in place by means of the nut 21.
  • the chamber 24 communicates with the interior of the drill collar through a passageway 28.
  • the upper portion of the fitting 23 is of reduced diameter and surrounded by a spring 29, the purpose of which will'be presently set forth. Adjacent its upper end this reduced part of the fitting a washer 32, this washer being secured to the end of the fitting 23 by means of a cap screw 33 or the like.
  • is a fitting having a lower sleeveportion 34, and an intermediate partition 35. Passageways 36 lead from the chamber 31 above this partition into the space surrounding the sleeve 34 within the drill collar.
  • the upper end of this fitting is open as at 38, and a short distance below its upper end the fitting is provided with an in-. ternal latching shoulder 39.
  • the upper end is slotted at 40 for the purpose of receiving the portion I! of the pawl l2 when the core barrel is pushed upwardly in the drill collar as during the taking of a core. It will be seen that when this occurs in the manner illustrated in Fig. 4, the core barrel will be positively held against rotation with respect to the drill stem, so that when the drill stem is rotated in taking the core, the core barrel will also-be rotated.
  • a tool which is used for removing the core barrel and its contents from the well, as well as for lowering the same into the well 44 apair of catcher arms 45.
  • the pin 46 mounted in enlarged holes in the upper ends of the arms 45 limit the outward movement of the lower ends of these arms.
  • Springs 41 are riveted or otherwise secured at their upper ends within the grooves 42 of the head, and at their lower ends fit within notches in the upper ends of the arms 45, respectively. These springs normally tend to force the upper ends of these arms outwardly, thus also forcing the lower ends apart, such movement being limited by the pin 46 as just explained.
  • the lower ends of these arms 45 are provided with hooks or the like 49 adapted to engage with the shoulder 39 at the upper end of the core barrel assembly.
  • these bifurcations are joined to form a bullet end 50 for enabling the tool upon being lowered into the well to pass freely by any obstruction that might be encountered, and for guiding the tool into the opening 38 at the upper end of the core barrel assembly when the same is being lowered for the purpose of retrieving the core barrel.
  • the tool illustrated in the upper portion of Fig. 1 and in Fig. 3 may be employed for either lowering the core barrel, or for raising the same, or for both.
  • the tool In the lowering of the core barrel, the tool is let down with the core barrel engaged with the hooks 49 until it reaches the lower end of the drill stem and the collar on the sleeve l8 *rests against the support 20 in the drill head.
  • the drill stem is then lowered until the core cutter 2
  • the core barrel assembly will be forced up slightly to the dotted line position indicated in Fig. 1, in which position one. of the slots 40 will engage the latch I1 and cause rotation of the drill stem to also rotate the core barrel and the core cutter.
  • the core is then taken, forcing the fluid within the core barrel upwardly past the valve 25 and out through the passage 28 during this process.
  • the retrieving tool When the core has been taken, the retrieving tool is again lowered into the well and guided by its bullet head 50 into the space provided therefor in the upper end of the fitting 34.
  • the hooks 49 willagain engage the shoulder 39 for the purpose of lifting the core barrel.
  • the enlarged portion 52 When this tool is lowered as just described, the enlarged portion 52 will encounter the lower portion of the latching arm l2 and will force it radially outwardly, thus disengaging this latching arm and moving it to such a position that the core barrel may readily be withdrawn from the hole.
  • the core barrel may be permitted to yield and move upwardly within the bit by compressing the spring 29. "The barrel is normally held by this spring, however, so that the cutter 2
  • a drill stem a core barrel adapted to move longitudinally within said drill stem, means in said drill stem movable with respect to the drill stem to engage a part of said core barrel to limit its upward movement in said drill stem, and means on said core barrel adapted to interengage with said first mentioned means when said core barrel is moved upwardly a relatively slight amount in said drill stem to prevent relative rotation of said drill stem and core barrel.
  • a drill stem 9. core barrel adapted to move longitudinally within said drill stem, a latch non-rotatable with respect to said drill stem adapted to normally overlie a portion of said core barrel to limit upward movement thereof, and means on said core barrel adapted to engage saLllatch to cause rotation of said core barrel with said drill steni during the coring operation.
  • a drill stem adapted to move longitudinally within said drill, stem, a radially mov: able latch non-rotatable with respect to said dril stern adapted when in its inner position to overlie '8, portion of said core barrel to limit upwari movement thereof, means yieldably urging s ai radially movable latch to its inner position, am means on said core barrel adapted to engage saic latch to cause rotation of said core barrel with said drill stem during the coring operation.
  • a drill stem adapted to move longitudinally within said drill stem, a sleeve non-rotatably mounted within said drill stem and having a lateral opening therethrough, a latch mounted within said opening for radial movement with respect to said sleeve and adapted when in its inner position to overlie a portion of such core barrel to limit upward movement thereof, and means yieldably urging said radially movable latch to its inner position.
  • a drill stem adapted to move longitudinally within said drill stem, a sleeve non-rotatably mounted within said drill stem and having a lateral opening therethrough, a latch mounted within said opening for radial movement with respect to said sleeve, and'adapted when in its inner position to overlie a portion of said core barrel-to limit upward movement thereof, means yieldably urging said radially movable latch to its inner position, and means on said core barrel adapted to engage said latch to cause rotation of said core barrel with saiddrill stem during the coring operation.
  • a drill stem adapted to move longitudinally within said drill stem, a sleeve mounted within said drill stem and having a lateral opening therethrough, means for preventing said sleeve from rotation with respect to said drill stem, a
  • latch mounted within said opening for radial means on said core barrel adapted to engage said latch to cause rotation of said core barrel with said drill stem during the coring operation.
  • a drill stem a core barrel adapted to move longitudinally within said drill stem, a sleeve mounted within said drill stem and having a lateral opening therethrough, key means for preventing said sleeve from rotation with respect to said drill stem, a latch mounted within said opening for radial movement with respect to said sleeve and adapted when in its inner position to overlie a portion of said core barrel to limit upward movement thereof, spring means yieldably urging said radially movable latch to its inner position, and an upwardly projecting part on said core barrel adapted to engage said latch to cause rotation of said barrel within said drill stem during the coring operation.
  • a drill stem a core barrel adapted to move longitudinally within said drill stem, means movably mounted within said drill stem for limiting upward movement of said core barrel in said drill stem, and means effective upon relatively slight upward movement of said core barrel within said drill stem to prevent relative rotation of said-drill stem and core barrel during coring operation.
  • a drill stem adapted to move longitudinally within said drill stem, means movably mounted within said drill stem for limiting upward movement of said core barrel in said drill stem, and means on said core barrel engageable by said first means to prevent relative rotation of said drill stem and core barrel during the coring

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  • 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)
  • Drilling Tools (AREA)
  • Processing Of Stones Or Stones Resemblance Materials (AREA)

Description

J2 .ta I M 4 Nov. 1,1938. Q ES v2,134,983
- CORE TAKING APPARATUS Filed July 6, 1936 I 24- 3 JA 6 3 Z8 .22 2/ o n .Jfokas. FT
Patented Nov. 1, 1938 UNITED STATES- CORE-TAKIN G APPARATUS John C. Stokes, Houston, Tex., assignor to Reed Roller Bit Company, Houston, Tex, a corporation of Texas Application July 6, 1936, Serial No. 88,979
9 Claims.
I securing the core barrel in place within the drill stem while a core is being taken, and for lowering the core barrel into and removing it from the hole.
It is an object of this invention to providea I simple and effective means within the drill stem for latching a core barrel in core taking position within the drill stem, and for preventing the rotation of such core barrel with respect to the drill stem during the taking of a core.
3 It is a further object of this invention to provide a means for retrieving the core barrel and drawing it up through the drill stem, which means will serve to release the device which holds the core barrel in place during the core taking operation so that the core barrel may be drawn up through the drill stem.
It is a. further object to provide a simple and effective latch for securing .the core barrel in place within the drill stem, which latch may be readily removed for replacement or repair.
Other objects and advantages of this invention will become apparent from the following description and the accompanying drawing, in which like numerals indicate corresponding parts throughout, it being understood, however, that said description and drawing are by way of illustration and example only, and are not to be taken as in any way a limitation upon the scope of this invention. This invention is limited in its scope only by the prior art, and by the terms of the appended claims.
In the drawing: Fig. 1 is a vertical cross section illustrating a core barrel latch constructed in accordance with this invention, together with a drill stem and core barrel, and the means for retrieving the core barrel;
Fig. 2 is a view similar to Fig. 1, but showing the lower end of the drill stem and bit with the core barrel in place therein; I
Fig. 3 is an, elevation illustrating the spear or device for retrieving the core barrel;
Fig. 4 is a horizontal cross section taken along the line 44 of Fig. 1.
Referring now to Fig. 1, the numeral 1 indicates the lower end of the lower section of drill pipe,
onto which is threadedly mounted the drill collar 2. At the lower end of the drill collar 2 the drill head 3 carrying blades 4 is threadedly mounted.
Adjacent its upper end, the drill collar is formed 5 with an internal shoulder at 5 adapted to receive a sleeve 6, this sleeve being held in place by the pin 1 on the lower end of the drill pipe I. Adjacent one side of the sleeve 6 a small groove 8 is formed for the purpose of receiving a pin 9 welded 10 into the drill collar at III, the purpose of this pin 9 being to prevent the sleeve 6 from rotating within the drill collar. I
At another point in the wall of the sleeve 6, this sleeve is slotted as illustrated at H for the 18 purpose of receiving'the pawl l2 which serves as the latch proper for holding the core barrel in place. This pawl 12 is pivoted at l3 and springpressed by means of a spring l4 so that it is radially movable, and is, constantly urged toward its 20 innermost position. The spring I4 bears within the. recess l5 formed in the wall of the drill collar opposite the sleeve 6, which recess serves to receive the shank portion l6 of the pawl l2 when the same is in its retracted or outermost position. This shank portion l6 also is adapted to contact with a portion of the sleeve 6 to limit the radial inward movement of the latch portion I! of thispawl.
The core barrel consists of a tubular member I8 having a short sleeve-like portion l9 connected at its lower end, provided with an external shoulder adapted'to rest upon the support 2|] within the drill head. At its lower end, this sleeve l 9 is provided with a core cutter having teeth 2|, and between the core cutter and the end of the sleeve [9 there is carried a core catcher which may be of customary form.
At its upper end the core barrel is provided with a fitting 23 having a chamber 24 adjacent its 40 lower end. 1 The passageway between this chamber 24 and the body of the core-barrel is con trolled by means of a ball valve 25 bearing against the valve seat member 26, this seat member in turn being held in place by means of the nut 21. The chamber 24 communicates with the interior of the drill collar through a passageway 28. I
The upper portion of the fitting 23 is of reduced diameter and surrounded by a spring 29, the purpose of which will'be presently set forth. Adjacent its upper end this reduced part of the fitting a washer 32, this washer being secured to the end of the fitting 23 by means of a cap screw 33 or the like.
Threadedly engaging the upper end of the sleeve 3| is a fitting having a lower sleeveportion 34, and an intermediate partition 35. Passageways 36 lead from the chamber 31 above this partition into the space surrounding the sleeve 34 within the drill collar. The upper end of this fitting is open as at 38, and a short distance below its upper end the fitting is provided with an in-. ternal latching shoulder 39. The upper end is slotted at 40 for the purpose of receiving the portion I! of the pawl l2 when the core barrel is pushed upwardly in the drill collar as during the taking of a core. It will be seen that when this occurs in the manner illustrated in Fig. 4, the core barrel will be positively held against rotation with respect to the drill stem, so that when the drill stem is rotated in taking the core, the core barrel will also-be rotated.
In Fig. 3, and in the upper portion of Fig, 1
there is illustrated a tool which is used for removing the core barrel and its contents from the well, as well as for lowering the same into the well 44 apair of catcher arms 45. The pin 46 mounted in enlarged holes in the upper ends of the arms 45 limit the outward movement of the lower ends of these arms. Springs 41 are riveted or otherwise secured at their upper ends within the grooves 42 of the head, and at their lower ends fit within notches in the upper ends of the arms 45, respectively. These springs normally tend to force the upper ends of these arms outwardly, thus also forcing the lower ends apart, such movement being limited by the pin 46 as just explained. It will be noted that the lower ends of these arms 45 are provided with hooks or the like 49 adapted to engage with the shoulder 39 at the upper end of the core barrel assembly. At the lower end of the bifurcations of the head 4| these bifurcations are joined to form a bullet end 50 for enabling the tool upon being lowered into the well to pass freely by any obstruction that might be encountered, and for guiding the tool into the opening 38 at the upper end of the core barrel assembly when the same is being lowered for the purpose of retrieving the core barrel.
It is to be noted that the tool illustrated in the upper portion of Fig. 1 and in Fig. 3 may be employed for either lowering the core barrel, or for raising the same, or for both. In the lowering of the core barrel, the tool is let down with the core barrel engaged with the hooks 49 until it reaches the lower end of the drill stem and the collar on the sleeve l8 *rests against the support 20 in the drill head. There is then dropped into the well a sleeve 5| which surrounds the cable or wire line, this sleeve 5| descending until it contactswith the bowed portions of the springs 41, causing prevent the upward movement of the core barrel.
The drill stem is then lowered until the core cutter 2| engages the bottom of the hole and is rotated for the purpose of cutting the core and forcing it to enter the core barrel l8. When the core cutter 2| first encounters the bottom of the hole the core barrel assembly will be forced up slightly to the dotted line position indicated in Fig. 1, in which position one. of the slots 40 will engage the latch I1 and cause rotation of the drill stem to also rotate the core barrel and the core cutter. The core is then taken, forcing the fluid within the core barrel upwardly past the valve 25 and out through the passage 28 during this process.
When the core has been taken, the retrieving tool is again lowered into the well and guided by its bullet head 50 into the space provided therefor in the upper end of the fitting 34. The hooks 49 willagain engage the shoulder 39 for the purpose of lifting the core barrel. When this tool is lowered as just described, the enlarged portion 52 will encounter the lower portion of the latching arm l2 and will force it radially outwardly, thus disengaging this latching arm and moving it to such a position that the core barrel may readily be withdrawn from the hole.
It is noted that if, during the cutting of the core, a hard formation is encountered, the core barrel may be permitted to yield and move upwardly within the bit by compressing the spring 29. "The barrel is normally held by this spring, however, so that the cutter 2| projects below the bit as illustrated in Fig. 2. a
It will be noted from the foregoing that a means has been provided within the drill stem for latching the core barrel in place therein, and for causing its rotation during the taking of a core. It will be further apparent that this latching member may be readily removed for replacement or repair, and that it will be moved out of latching position by the spear or retrieving device when the same is lowered to retrieve the core barrel. It is thus apparent that means has been provided for carrying out all the objects and advantages sought by this invention.
Having described my invention, I claim:
1. In a device of the character described, a drill stem, a core barrel adapted to move longitudinally within said drill stem, means in said drill stem movable with respect to the drill stem to engage a part of said core barrel to limit its upward movement in said drill stem, and means on said core barrel adapted to interengage with said first mentioned means when said core barrel is moved upwardly a relatively slight amount in said drill stem to prevent relative rotation of said drill stem and core barrel.
2. In a device of the character described, a drill stem, 9. core barrel adapted to move longitudinally within said drill stem, a latch non-rotatable with respect to said drill stem adapted to normally overlie a portion of said core barrel to limit upward movement thereof, and means on said core barrel adapted to engage saLllatch to cause rotation of said core barrel with said drill steni during the coring operation.
3. In a. device of the character described, a drill stem, a core barrel adapted to move longitudinally within said drill, stem, a radially mov: able latch non-rotatable with respect to said dril stern adapted when in its inner position to overlie '8, portion of said core barrel to limit upwari movement thereof, means yieldably urging s ai radially movable latch to its inner position, am means on said core barrel adapted to engage saic latch to cause rotation of said core barrel with said drill stem during the coring operation.
4. In a device of the character described, a drill stem, a core barrel adapted to move longitudinally within said drill stem, a sleeve non-rotatably mounted within said drill stem and having a lateral opening therethrough, a latch mounted within said opening for radial movement with respect to said sleeve and adapted when in its inner position to overlie a portion of such core barrel to limit upward movement thereof, and means yieldably urging said radially movable latch to its inner position.
5. In a device of the character described, a drill stem, a core barrel adapted to move longitudinally within said drill stem, a sleeve non-rotatably mounted within said drill stem and having a lateral opening therethrough, a latch mounted within said opening for radial movement with respect to said sleeve, and'adapted when in its inner position to overlie a portion of said core barrel-to limit upward movement thereof, means yieldably urging said radially movable latch to its inner position, and means on said core barrel adapted to engage said latch to cause rotation of said core barrel with saiddrill stem during the coring operation.
6. In a device of the character described, a drill stem, a core barrel adapted to move longitudinally within said drill stem, a sleeve mounted within said drill stem and having a lateral opening therethrough, means for preventing said sleeve from rotation with respect to said drill stem, a
latch mounted within said opening for radial means on said core barrel adapted to engage said latch to cause rotation of said core barrel with said drill stem during the coring operation.
'7. In a device of the character described, a drill stem, a core barrel adapted to move longitudinally within said drill stem, a sleeve mounted within said drill stem and having a lateral opening therethrough, key means for preventing said sleeve from rotation with respect to said drill stem, a latch mounted within said opening for radial movement with respect to said sleeve and adapted when in its inner position to overlie a portion of said core barrel to limit upward movement thereof, spring means yieldably urging said radially movable latch to its inner position, and an upwardly projecting part on said core barrel adapted to engage said latch to cause rotation of said barrel within said drill stem during the coring operation.
8. In a device of the character described, a drill stem, a core barrel adapted to move longitudinally within said drill stem, means movably mounted within said drill stem for limiting upward movement of said core barrel in said drill stem, and means effective upon relatively slight upward movement of said core barrel within said drill stem to prevent relative rotation of said-drill stem and core barrel during coring operation.
9. In a device of the character described, a drill stem, a core barrel adapted to move longitudinally within said drill stem, means movably mounted within said drill stem for limiting upward movement of said core barrel in said drill stem, and means on said core barrel engageable by said first means to prevent relative rotation of said drill stem and core barrel during the coring
US88979A 1936-07-06 1936-07-06 Core-taking apparatus Expired - Lifetime US2134988A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2890022A (en) * 1957-09-03 1959-06-09 Jr Lothrop L Brown Replaceable drill bit
US3004614A (en) * 1958-10-20 1961-10-17 Sprague & Henwood Inc Core-taking apparatus
US3127943A (en) * 1962-03-05 1964-04-07 Christensen Diamond Prod Co Wire line core barrel
US3420322A (en) * 1966-08-10 1969-01-07 Sprague & Henwood Inc Core taking apparatus

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2890022A (en) * 1957-09-03 1959-06-09 Jr Lothrop L Brown Replaceable drill bit
US3004614A (en) * 1958-10-20 1961-10-17 Sprague & Henwood Inc Core-taking apparatus
US3127943A (en) * 1962-03-05 1964-04-07 Christensen Diamond Prod Co Wire line core barrel
US3420322A (en) * 1966-08-10 1969-01-07 Sprague & Henwood Inc Core taking apparatus

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