US761332A - Core-drill. - Google Patents

Core-drill. Download PDF

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Publication number
US761332A
US761332A US16815303A US1903168153A US761332A US 761332 A US761332 A US 761332A US 16815303 A US16815303 A US 16815303A US 1903168153 A US1903168153 A US 1903168153A US 761332 A US761332 A US 761332A
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core
barrel
drill
shell
water
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US16815303A
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Frederick Stone
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DIAMOND DRILL CONTRACTING Co
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DIAMOND DRILL CONTRACTING Co
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    • EFIXED CONSTRUCTIONS
    • E21EARTH DRILLING; MINING
    • E21BEARTH DRILLING, e.g. DEEP 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, core extractors
    • E21B25/10Formed core retaining or severing means
    • E21B25/12Formed core retaining or severing means of the sliding wedge type

Definitions

  • My invention relates tok improvements in drilling apparatus of the type employedusually in prospecting for precious metals, coal, andthe likeandV which is adapted in penetrating into the earth to remove a solid section or core of allstratapassed through for the purpose 'ofvdetermining their depth and character.
  • Figure 1 is a verticalcentral section of my invention.
  • Fig. 2 is a vertical central section of a modification.
  • Fig. 3 is a vertical central section of a second modification.
  • Fig. 4 is a transverse section on line m Fig. l.
  • Fig. 5 is a 'transverse section on line y y, Fig. 1.
  • Fig. 6 is a-transversesection on line p 1J, Fig. 2;
  • Fig. 7 is a transverse section on line e e, Fig. 2.
  • v 1 is a verticalcentral section of my invention.
  • Fig. 2 is a vertical central section of a modification.
  • Fig. 3 is a vertical central section of a second modification.
  • Fig. 4 is a transverse section on line m Fig. l.
  • Fig. 5 is a 'transverse section on line y y, Fig. 1.
  • Fig. 6 is a-transversesection on line
  • A represents a core-barrel casing or shell adapted to be connected rigidly to and to be rotatable with the hollow drill-rod B, by which the drill is operated from the surface.
  • the core-barrel is the core-barrel, supported inside of and concentric withcasing A and out of Contact therewith, so as to leave an intervening space 3, through which water is fed to the point of the drill.
  • the casing and core-barrel are of suitable length and diameter, dependent on the size. of the core to be extracted and the nature of the formation encountered.
  • the drills are adapted to bore a hole from one andone-half to two or more inches in diameter and to remove a core from one to two or more inches thick, according to the size of the drill, and three to four or more feet in length.
  • the core-lifter comprises a cylindrical section with an annular series of ioles V5 bored in its walls lengthwise of the section and communicating with the water-space 3 when the section is in position on the end ofthe casing.
  • the lifter has an annular thickened portion- 6 intermediate of its threaded ends, in Which are one or more (here shown three) holes, as 7, inclined downwardly and inwardly and in which the balls 8 are reciprocable.
  • a ball is inserted into each hole 7 before the lifter is screwed into the casing, the end/of the latter serving to close the upper ends of the holes and keep in the balls.
  • holes are slightly reduced to prevent the balls falling out, but stilll allowingthem to project into the core-space to engage the sides of the core and insure' its being drawn out with the drill when the latter is removed from the hole.
  • FIG. 9 is an annular bit provided with an .inte. rior-threaded portion engaging the correspondingly-threaded lower end of the core-
  • the lowerends of the lifter Yand having a thickened lower portion with a central opening coincident and of api'v yproizirnately equal diameter with the opening inthe core-barrel and lifter.
  • the inner surportion andthe reinforced portion is beveled,-
  • the bit' is set with the usual diamond or carbonl abrading members on 'its lower face and inner and outer edges.l .As the bit is rotated and fed forward by the turning and advancement of the drill-rods and casing the diamonds chip and grind away the i rock in an annular hole, leaving a solid cylindrical core intact ⁇ in the center', which gradually passes up into the core-barrel.
  • the gravity-actuated balls 8 grip the core to cause it to be broken offand heldin the barrel and carried out with it.
  • the balls are normally retracted within the inclined holes, being pushed'back by the core and giving free entry to the core within the barrel.
  • the drill-rod is of eXtra heavy pipe and is made in sections of suitable lengths, usually of five or ten feet, and put together with hol-A low steel couplings.
  • the current of water is pumped through the drill-rod,corebarrel, and bit and returns to the surface outside of the casing and drill-rod sections.
  • the difficulty with the core-drills ordinarily in use is as follows, according as the drill is a single-tube drill .or a so-called doubletube drill: In the single-tube drills the heavy pressure of the water column in the core-barrel and upon the core (except in very rare cases Where the rock is solid and the core remains intact) forces the broken pieces of the core against the bit and diamonds and against the core-piece that is still unbroken from the solid rock, and the grinding and blocking of these pieces destroy a great percentage of core, which instead of coming up in the corebarrel when the rod is pulled up is washed up in the cuttings. This process in addition to destroying a considerable portion of the core is destructive of the diamonds, inasmuch as where the rock is hard and broken the water forces the small fragments to the bottom of the hole into contact with the inside diamonds, chipping and breaking them.
  • the core-barrel admits the water from the rod at a point adjacent to the bit, but returns it all to the surface, just as with the single-tube drill, beneath the bit and outside the shell and rod.
  • the objection here is that on the drill being lowered into the hole and drilling operations commenced the core-barrel is filled with water under pressure of from seventy to eighty pounds or more per square inch, which acts as a cushion above the forming core to prevent the free progress of the core to the top of the barrel.
  • the full pressure of the water being on the core near the bottom of the hole causes the broken pieces to bind and .block and wear away the core and destroy the diamonds, as with the single-tube barrel.
  • the main object of the present invention is to provide a core-barrel wherein a portion of the water entering the barrel above the bit will be returned to the surface through the core-barrel to assist rather than retard in the upward progress of the core and to prevent the broken pieces from wedging and grinding and to keepthe bottom of the hole clear, and thus protect the diamonds.
  • Fig. 3 shows a modification in which the shell and core-barrel are both rotatable. In either case the return water is divided and part returned beneath the bits and outside the shell and rod and part through the shell and outside the rod-sections. r1 ⁇ his upward circu lation of the water may be effected in a variety of ways. In the present instance l have shown the following means for admitting water from the rod to the space 3 and after delivering it to the core-barrel returning a portion of it thence through the upper part of the barrel and outside the rod to the surface.
  • a centraliy-perforated plug 11 is screwed into the upper end of shell A just below the point of attachment of the lower drill-rod section. This central perforation is screw-threaded to receive the threaded stud or hanger 12, which is to support the core-barrel.
  • the stud 12 has a fiange or head 13, which in Fig. 1 is shown as provided with an annular groove or race to accommodate a row of balls 14C.
  • rIhe core-barrel is formed with an interior annular projection 15, adapted to embrace the stud. Between the latter and projection 15 is intel'- posed a bearing plate having an annular groove on its under side corresponding with the groove in head 13 to receive the balls 14, which thus support the core-barrel.
  • a suitable packing 16 affords a water-tight joint hetween the part 15 and the stud and at the same time does not prevent the stud turning relative to the core-barrel.
  • the space above plug 11 is in communication with space 3 below through a series of inclined ports 19.
  • the shell A, the plug 11, and the stud or hanger 12 are perforated coincidently and correspondingly threaded to receive a threaded centrally-perforated plug 20, whose outer ends are fiush with the sides of the shell.
  • ',lhe portion of hanger 12 between its head and the perforation made for the reception of the hori- Zontal plug 2O is centrally perforated, as at 21, while plug 20 has a perforation 22, adapted to register with passage-way 21 and forming the communication between the latter and the horizontal passage-way 23 of plug 20.
  • '.lihus water may pass from the rod through ports 19 down into space 3 between the shell -and core-barrel, thence through holes 5 in the core-lifter into the core-barrel just above the bit.
  • part of the water passes down around the bit and up outside the shell and rod.
  • the rest finds its way up between the core and the inside of the core-barrel to the top of the barrel, whence it passes through passage-way 21 of the hanger, through the radial opening 22 in plug 2() into the longitudinal passage-way 23 of plug 20, and thence discharges from opposite sides of the shell and passes up finally to the surface outside the drill-rod sections.
  • Fig. 2 a modified form of con- IOO ⁇ and has lateral. perforations registering with the transverse perforations 23 in plug 11.
  • a perforated cap 24 screws onto the lower end of the hanger-pin 12, and arow of balls 18 is interposed between. cap 24 and the adjacent end-of plug 11.
  • Suitable packing 16 is provided to prevent leakage between the rotatable part 11 and the non-rotatable hanger.
  • the core-barrel 2 is carried by cap 24. Water passes from the space above the connection 11 through cored passages 19 into the annular space 3 between the shell and core, passes into the core-barrel, and part returns to the riorly to the shell and pump-rod.
  • theV combination with a rotatable hollow rod and la shell rigid therewith; a concentric inner core-barrel, means for delivering water into the core-barrel from the rod, and means for discharging water from the top of the corebarrel exterior to the said rod.
  • a drill of the character described the combination with a hollow drill-rod and a rotatable shell, of a core-barrel suspended within the shell, and means for delivering water from the rod intothe core-barrel, and means for returning water tothe surface through thel top of the barrel and vexterior to the ⁇ said rod.
  • the combination with a hollow rod and a rotatable shell of an inner core-barrel means for supporting the latter within the barrel, means for delivering water from the space above the core-barrel into the space between the barrel and shell and means for returning Water from the interior of the core-barrel through the top of the barrel and exterior to the casing and drill-rod.
  • a drill of the character described the combination of a rotatable shell, a concentric inner core-barrel, an annular bitconnected with the shell, means for delivering water from the space above the core-barrel-into the core-barrel adjacent to the bit whereby a portion of the water returns to the surface beneath the bit and exterior to the shell, and means for discharging a portionof the Water through the upper part of the core-barrel exterior 'to the casing for the purpose described.
  • the combination with-a rotatable shell of a concentric inner core-barrel and means for supporting said barrel within the shell said means including a central hanger rigidly connected with the shell, and engaging means with said hanger upon the core-barrel, said hanger having passageways communicating with the space exterior to the shell and with the interior of the core-barrel.
  • a drill of the character described With a shell', of a concentric inner core-barrel, and means for su pporting the latter within the shell, said means including a perforated plug as 11 secured in the shell above the core-barrel, a hanger rigid with the plug and having a water-passage connecting the space in the top of the core-barrel with the outside of the shell, an internal 'projection on the core-barrel engaging said hanger, and antifrictional ballbearings supporting the barrel on the hanger.

Description

PATENTED MAY 31, 19,04.
Y i vRSTQNE.
GORE DRILL. APIPLIUATION FILED AUG. 4, 1903.
ZBHEBTS-BEEET 2.
. H0 MODEL.
' wal/Wma,
UNI-TED `STA-Tiss Patented May 3i, 1904, l
PATENT OFFICE.
FREDERICK STONE, OF SPOKANE, lWASHlNGTON, ASSIGNOR TO DIAMOND DRILL OONIRACIINGv COMPANY, OF SPOKANE, WASHINGTON, A OOR- roRATioN. j
SPECIFICATION forminggpart of Letters Patent No. 761,332, dated May 31, 1904.
Y CORE-DRILL.
Applicatiouled August 4,1903. Serial No. 168,153. (Nomodel.) i?, g f' g T 1J/Z whom, it concern: e Y
Beit known that I, FREDERICK STONE, a citizen of the UnitedStates, residing at Spokane,
' in the county of Spokane and State'of Washington, have invented new and useful Improvements in Core-Drills, of which the following isa specification.
My invention relates tok improvements in drilling apparatus of the type employedusually in prospecting for precious metals, coal, andthe likeandV which is adapted in penetrating into the earth to remove a solid section or core of allstratapassed through for the purpose 'ofvdetermining their depth and character.
It consists of the parts and the construction and operation of parts hereinafter more fully described, having reference tothe accompanying drawings, in whichl Figure 1 is a verticalcentral section of my invention. Fig. 2 is a vertical central section of a modification. Fig. 3 isa vertical central section of a second modification. Fig. 4 is a transverse section on line m Fig. l. Fig. 5 is a 'transverse section on line y y, Fig. 1. Fig. 6 is a-transversesection on line p 1J, Fig. 2; Fig. 7 is a transverse section on line e e, Fig. 2. v 1
A represents a core-barrel casing or shell adapted to be connected rigidly to and to be rotatable with the hollow drill-rod B, by which the drill is operated from the surface.
2 is the core-barrel, supported inside of and concentric withcasing A and out of Contact therewith, so as to leave an intervening space 3, through which water is fed to the point of the drill. The casing and core-barrel are of suitable length and diameter, dependent on the size. of the core to be extracted and the nature of the formation encountered. Usually the drills are adapted to bore a hole from one andone-half to two or more inches in diameter and to remove a core from one to two or more inches thick, according to the size of the drill, and three to four or more feet in length.
4 is the core-lifter, screwing into the lower end of casing A and designed to abut against the end of the core-barrel, which latter does not extend quite the full length of the casing.
The core-lifter comprises a cylindrical section with an annular series of ioles V5 bored in its walls lengthwise of the section and communicating with the water-space 3 when the section is in position on the end ofthe casing.
The lifter has an annular thickened portion- 6 intermediate of its threaded ends, in Which are one or more (here shown three) holes, as 7, inclined downwardly and inwardly and in which the balls 8 are reciprocable. A ballis inserted into each hole 7 before the lifter is screwed into the casing, the end/of the latter serving to close the upper ends of the holes and keep in the balls. holes are slightly reduced to prevent the balls falling out, but stilll allowingthem to project into the core-space to engage the sides of the core and insure' its being drawn out with the drill when the latter is removed from the hole.
9 is an annular bit provided with an .inte. rior-threaded portion engaging the correspondingly-threaded lower end of the core- The lowerends of the lifter Yand having a thickened lower portion with a central opening coincident and of api'v yproizirnately equal diameter with the opening inthe core-barrel and lifter. The inner surportion andthe reinforced portion is beveled,-
as at 10, to allow` for'water to pass outward and downward from` the openings 7v in the lifter.` i i The bit'is set with the usual diamond or carbonl abrading members on 'its lower face and inner and outer edges.l .As the bit is rotated and fed forward by the turning and advancement of the drill-rods and casing the diamonds chip and grind away the i rock in an annular hole, leaving a solid cylindrical core intact` in the center', which gradually passes up into the core-barrel. When theapparatus is drawn to the surface, the gravity-actuated balls 8 grip the core to cause it to be broken offand heldin the barrel and carried out with it. During theladvancement of the drill into the rock the balls are normally retracted within the inclined holes, being pushed'back by the core and giving free entry to the core within the barrel.
It lis necessary in all diarnond-core-drill` Work when the drill is in operation to force a IOO current of water to the bottom of the hole in order to wash away the cuttings and keep the diamonds cool.
The drill-rod is of eXtra heavy pipe and is made in sections of suitable lengths, usually of five or ten feet, and put together with hol-A low steel couplings. The current of water is pumped through the drill-rod,corebarrel, and bit and returns to the surface outside of the casing and drill-rod sections. p
The difficulty with the core-drills ordinarily in use is as follows, according as the drill is a single-tube drill .or a so-called doubletube drill: In the single-tube drills the heavy pressure of the water column in the core-barrel and upon the core (except in very rare cases Where the rock is solid and the core remains intact) forces the broken pieces of the core against the bit and diamonds and against the core-piece that is still unbroken from the solid rock, and the grinding and blocking of these pieces destroy a great percentage of core, which instead of coming up in the corebarrel when the rod is pulled up is washed up in the cuttings. This process in addition to destroying a considerable portion of the core is destructive of the diamonds, inasmuch as where the rock is hard and broken the water forces the small fragments to the bottom of the hole into contact with the inside diamonds, chipping and breaking them.
I/Vith the ordinary double-tube core-drill the core-barrel admits the water from the rod at a point adjacent to the bit, but returns it all to the surface, just as with the single-tube drill, beneath the bit and outside the shell and rod. The objection here is that on the drill being lowered into the hole and drilling operations commenced the core-barrel is filled with water under pressure of from seventy to eighty pounds or more per square inch, which acts as a cushion above the forming core to prevent the free progress of the core to the top of the barrel. The full pressure of the water being on the core near the bottom of the hole causes the broken pieces to bind and .block and wear away the core and destroy the diamonds, as with the single-tube barrel.
The main object of the present invention is to provide a core-barrel wherein a portion of the water entering the barrel above the bit will be returned to the surface through the core-barrel to assist rather than retard in the upward progress of the core and to prevent the broken pieces from wedging and grinding and to keepthe bottom of the hole clear, and thus protect the diamonds.
Where these drills are to be used in drilling for salt or coal or other friable material, the core-barrel is designed to remain stationary relative to its casing, which alone revolves. Such is the construction contemplated in Fig. 1. Fig. 3 shows a modification in which the shell and core-barrel are both rotatable. In either case the return water is divided and part returned beneath the bits and outside the shell and rod and part through the shell and outside the rod-sections. r1`his upward circu lation of the water may be effected in a variety of ways. In the present instance l have shown the following means for admitting water from the rod to the space 3 and after delivering it to the core-barrel returning a portion of it thence through the upper part of the barrel and outside the rod to the surface.
A centraliy-perforated plug 11 is screwed into the upper end of shell A just below the point of attachment of the lower drill-rod section. This central perforation is screw-threaded to receive the threaded stud or hanger 12, which is to support the core-barrel. The stud 12 has a fiange or head 13, which in Fig. 1 is shown as provided with an annular groove or race to accommodate a row of balls 14C. rIhe core-barrel is formed with an interior annular projection 15, adapted to embrace the stud. Between the latter and projection 15 is intel'- posed a bearing plate having an annular groove on its under side corresponding with the groove in head 13 to receive the balls 14, which thus support the core-barrel. A suitable packing 16 affords a water-tight joint hetween the part 15 and the stud and at the same time does not prevent the stud turning relative to the core-barrel.
Between the lower end of plug 11 and the upper end of the core-barrel is interposed the annular bearing plates or boxes 17 17', carrying a second supporting-row of balls 18.
The space above plug 11 is in communication with space 3 below through a series of inclined ports 19.
The shell A, the plug 11, and the stud or hanger 12 are perforated coincidently and correspondingly threaded to receive a threaded centrally-perforated plug 20, whose outer ends are fiush with the sides of the shell. ',lhe portion of hanger 12 between its head and the perforation made for the reception of the hori- Zontal plug 2O is centrally perforated, as at 21, while plug 20 has a perforation 22, adapted to register with passage-way 21 and forming the communication between the latter and the horizontal passage-way 23 of plug 20. '.lihus water may pass from the rod through ports 19 down into space 3 between the shell -and core-barrel, thence through holes 5 in the core-lifter into the core-barrel just above the bit. Here part of the water passes down around the bit and up outside the shell and rod. The rest finds its way up between the core and the inside of the core-barrel to the top of the barrel, whence it passes through passage-way 21 of the hanger, through the radial opening 22 in plug 2() into the longitudinal passage-way 23 of plug 20, and thence discharges from opposite sides of the shell and passes up finally to the surface outside the drill-rod sections.
In Fig. 2 is shown a modified form of con- IOO `and has lateral. perforations registering with the transverse perforations 23 in plug 11. A perforated cap 24 screws onto the lower end of the hanger-pin 12, and arow of balls 18 is interposed between. cap 24 and the adjacent end-of plug 11. Suitable packing 16 is provided to prevent leakage between the rotatable part 11 and the non-rotatable hanger. The core-barrel 2 is carried by cap 24. Water passes from the space above the connection 11 through cored passages 19 into the annular space 3 between the shell and core, passes into the core-barrel, and part returns to the riorly to the shell and pump-rod.
Having thus 'described my invention, what I claim, and desire to secure by Letters Patent, is-
surface through passages 21 and 23and exte- 1. In a drill of the character described, theV combination with a rotatable hollow rod and la shell rigid therewith; a concentric inner core-barrel, means for delivering water into the core-barrel from the rod, and means for discharging water from the top of the corebarrel exterior to the said rod.
2. In a drill of the character described the combination with a hollow drill-rod and a rotatable shell, of a core-barrel suspended within the shell, and means for delivering water from the rod intothe core-barrel, and means for returning water tothe surface through thel top of the barrel and vexterior to the `said rod.
3. In a drill of the character' described, the combination with a hollow rod and a rotatable shell of an inner core-barrel, means for supporting the latter within the barrel, means for delivering water from the space above the core-barrel into the space between the barrel and shell and means for returning Water from the interior of the core-barrel through the top of the barrel and exterior to the casing and drill-rod.
:4. In a drill of the character described the combination of a rotatable shell, a concentric inner core-barrel, an annular bitconnected with the shell, means for delivering water from the space above the core-barrel-into the core-barrel adjacent to the bit whereby a portion of the water returns to the surface beneath the bit and exterior to the shell, and means for discharging a portionof the Water through the upper part of the core-barrel exterior 'to the casing for the purpose described.
5. In adrill of the character described,lthe combination of a rotatable shell, a concentric inner core-barrel, means for delivering water between the core-barrel and shell from above, a core-lifterl rotatable with said shell and having Water passage-Ways registering with the space between the barrel and shell and discharging into the core-space, an annular bit below the core-lifter, and'means for the passage of water from the top of the core-barrel exterior to the shell.
6. In a drill of the character described, the combination with-a rotatable shell of a concentric inner core-barrel and means for supporting said barrel within the shell, said means including a central hanger rigidly connected with the shell, and engaging means with said hanger upon the core-barrel, said hanger having passageways communicating with the space exterior to the shell and with the interior of the core-barrel.
7. In a drill of the character described the combination With a shell', of a concentric inner core-barrel, and means for su pporting the latter within the shell, said means including a perforated plug as 11 secured in the shell above the core-barrel, a hanger rigid with the plug and having a water-passage connecting the space in the top of the core-barrel with the outside of the shell, an internal 'projection on the core-barrel engaging said hanger, and antifrictional ballbearings supporting the barrel on the hanger.
In testimony whereof I have hereunto set my hand in presence of two subscribing witnesses.
FREDERICK STONE.
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