US3743037A - Rig for rotary drilling of holes and shafts - Google Patents
Rig for rotary drilling of holes and shafts Download PDFInfo
- Publication number
- US3743037A US3743037A US00136520A US3743037DA US3743037A US 3743037 A US3743037 A US 3743037A US 00136520 A US00136520 A US 00136520A US 3743037D A US3743037D A US 3743037DA US 3743037 A US3743037 A US 3743037A
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- United States
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- drilling
- shafts
- rig
- tools
- pilot
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- Expired - Lifetime
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- 238000005553 drilling Methods 0.000 title claims abstract description 93
- 239000010432 diamond Substances 0.000 description 4
- 239000011435 rock Substances 0.000 description 4
- 229910003460 diamond Inorganic materials 0.000 description 3
- 238000005520 cutting process Methods 0.000 description 2
- 230000006378 damage Effects 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 241001611950 Tarasa Species 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 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
- 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
- E21B10/28—Drill bits with leading portion, i.e. drill bits with a pilot cutter; Drill bits for enlarging the borehole, e.g. reamers with non-expansible roller cutters
Definitions
- the present invention relates to rigs for the rotary drilling of holes and shafts, particularlyfor holes from 300 to 4,200 mm and more in diameter. This does not exclude the possibility of using the present invention for rigs for the rotary drilling of holes and shafts of smaller and greater diameters.
- a, 14/20 are rigs for rotary drilling of holes and shafts, comprising a drilling stringwith a pilot drilling tool disposed coaxially therewith, and a body mounted on the drilling string by means of bearings and carrying side shafts radially displaced relative to the pilot drilling tool.
- the side shafts are mounted by one of their end portions in bearings in the body and have at the other end portions which protrude from the body, with a drilling tool on such protruding portion disposed above the pilot drilling tool and partially overlapping the the pilot tool in such a manner that in the course of drilling, there takes place a stepwise destruction of the bottom hole along its whole cross section, with the side shafts being imparted rotation by the drilling string through chain drives.
- the present invention has as its object the provision of such a rig that, due to a different arrangement of the body and side shafts, is sufficiently reliable and more efficient in operation, and simpler to manufacture.
- the body is rigidly connected with the drilling string, and the side shafts are mounted in the body loosely, whereby the side shafts can rotate about their axes irrespective of one another.
- a rig for drilling holes and shafts which, as compared to conventional rigs, possesses a number of advantages.
- the present rig operates irrespective of the value of deepening of the drilling tools into the rock and the state of the bottom hole thereby making it possible to vary within a wide range the drilling practices, as well as to ream the sections which were previously drilled. All this raises the efficiency of drilling and makes the operation more economical.
- FIG. 1 shows a general view of the rig for drilling holes and shafts, with one row of side drilling tools, according to the invention, comma the view being partly in elevation and partly in section;
- FIG. 2 shows a general view in elevation of the rig for drilling holes and shafts of a large diameter, with two rows of side drilling tools, according to the invention
- FIG. 3 is a section taken along line III-III of FIG. 2, the view looking in the direction of the arrows;
- FIG. 4 is a section taken along line lV--IV of FIG. 2, the view looking in the direction of the arrows.
- a rig for drilling holes and shafts comprises a drilling string 1, a body 2 with a central pipe 3, shafts 4 with bearings 5, weighting loads 6, a nut 7, a centrally disposed pilot drilling tool 8 and side drilling tools 9.
- the body 2 is rigidly connected with the drilling string 1 by means of the central pipe 3 which is either welded to the body, made integral therewith, or is connected thereto by any other method.
- Mounted on the body 2 in the bearings 5 by one of their end portions are the side shafts 4, so that each of the shafts 4 can rotate about its axis freely and independently of the other shafts.
- drilling tools 9 mounted at one end the same level and radially displaced relative to the pilot drilling tool 8 which is arranged coaxially with respect to the drilling string 1, with the side drilling tools 9 partially overlapping the pilot drilling tool 8.
- Both single-cone, spherical or tapered, three-cone, multicone, and three-disc multi-disc, hits as well as blade or diamond drill bits and heads can be used as the drilling tools 8 and 9.
- the present rig makes it possible to carry out diamond drilling of holes, for which purpose a diamond drill bit, for example, 212-214 mm in diameter can be used as a pilot drilling tool, and heads covered with diamonds as the side tools.
- a diamond drill bit for example, 212-214 mm in diameter can be used as a pilot drilling tool, and heads covered with diamonds as the side tools.
- the rig may be constructed as shown in FIGS. 2,3, and 4, and comprise a drilling string la, a pilot drilling tool 10 of, for instance, a cutting type arranged centrally, and a body incorporating a central pipe 11 provided with a support plate 12 and three cross pieces l3, l4 and 15 carrying side shafts l6, l7 and 18, respectively, with tools (bits) 19, 20 and 21 radially displaced relative to the pilot drilling tool 10 which is disposed coaxially to the drilling string 1a;
- the side shafts l6, l7 and 18 are installed in the cross pieces 13, 14 and 15 in a manner similar to the shafts 4.
- the cross pieces l3, l4 and 15 are disposed one above another and are tightened to the support plate 12 by bolts 22 to form a monolithic system.
- the side tools are radially displaced from the tool 10 over various distances so that the tools 19 of the lower cross piece 13 partially overlap the pilot drilling tool 10; the tools 20 of the cross piece 14 partially overlap the tools 19, and the tools 21 of the cross piece partially overlap the tools 20.
- a stepwise destruction of the bottom hole over the entire cross section is provided.
- This embodiment of the rig makes it possible to form a hole of a predetermined diameter either immediately, or by way of preliminary drilling of the hole by this rig with only one cross piece 13 (without using the cross pieces 14 and 15), to be followed by its reaming by means of the same rig using this time also the cross pieces 14 and 15.
- the rig shown in FIG. 1 functions as follows:
- the rig is rotated by means of the drilling string 1, and a pilot hole is drilled by the central tool 8.
- the tools 9 connected to the side shafts 4 are imparted a transfer motion about the axis of the rig by the rotation of the drilling string 1.
- each of the side tools is imparted rotation independently of one another about its axis by contact with the bottom hole while drilling the rock along an annular area around the bore formed by the pilot tool.
- the cuttings are delivered into the drilling string through openings (not shown in the drawing) provided in the pilot tool.
- a rig for the rotary drilling of holes and shafts comprising a drilling string; a pilot drilling tool arranged coaxially relative to said drilling string; a body for said rig rigidly connected to said drilling string, side shafts carried by said body and being displaced radially relative to said pilot drilling tool; said side shafts having opposite end portions, bearings in said body in which one of the end portions of the side shafts is mounted to allow the side shafts to be capable of rotating freely about their axes, other end portions of the side shafts protruding from the body; and drilling tools secured to the protruding end portions of said side shafts and being disposed above said pilot drilling tool so that said side drilling tools partially overlap the pilot drilling tool.
- the rig as claimed in claim 1 including a plurality of vertically spaced sets of side drilling tools, with the uppermost set of side tools overlapping the side drilling tools of the set therebelow.
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Fluid Mechanics (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Earth Drilling (AREA)
Abstract
A rig for rotary drilling, in which a pilot drilling tool is disposed coaxially relative to the drilling string and side drilling tools are radially displaced with respect to the pilot drilling tool, with the side tools rotating freely and partially overlapping the pilot tool drilling tool and disposed above the latter in a body which is rigidly connected to the drilling string.
Description
O Umted States Patent 11 1 1111 3,743,037
Bulakh et al. 1 July 3, 1973 [5 1 RIG FOR ROTARY DRILLING 0F HOLES .323.322 :38: g ve 7/ 23 entice... AND 2.039.551 5/1936 Phipps 175/354 [76] Inventors: Georgy lvanovicll Bulakh, 2,208,530 7/l940 Thompson l75/335 U.S.S.R.
[22] Filed: Apr. 22, 1971 211 Appl.No.: 136520 [521 US. Cl 175/334, 175/391, 175/354 [51] int.Cl 1221b 9/24 [58] Field of Search l75/334, 335, 354, 175/391, 345
[56] References Cited UNITED STATES PATENTS 2,703,698 3/1955 Westerman 175/334 l 1 E I 1 1 f:
1 E a I i i k I l l I l Oktyabrsky prospekt, 365, kv. 29, Ljubertsy Moskovskoi Oblasti; Vladimir Alexnndrovich Vysotsky, naberezhnaya Tarasa Shevchenko, l/2, kv. 270, Moscow, both of France l75/334 Primary Examiner-James A. Leppink Assistant Examiner--Richard E. Favreau Attorney-Holman & Stern ABSTRACT A rig for rotary drilling, in which a pilot drilling tool is disposed coaxially relative to the drilling string and side drilling tools are radially displaced with respect to the pilot drilling tool, with the side tools rotating freely and partially overlapping the pilot tool drilling tool and disposed above the latter in a body which is rigidly connected to the drilling string.
2 Claims, 4 Drawing Figures RIG FOR ROTARY DRILLING OF HOLES AND SHAFTS BACKGROUND OF THE INVENTION The present invention relates to rigs for the rotary drilling of holes and shafts, particularlyfor holes from 300 to 4,200 mm and more in diameter. This does not exclude the possibility of using the present invention for rigs for the rotary drilling of holes and shafts of smaller and greater diameters.
PRIOR ART Already known in the art, for instance, from GFR Patent No. 881,484, of June 29, 1953, C1. a, 14/20, are rigs for rotary drilling of holes and shafts, comprising a drilling stringwith a pilot drilling tool disposed coaxially therewith, and a body mounted on the drilling string by means of bearings and carrying side shafts radially displaced relative to the pilot drilling tool. The side shafts are mounted by one of their end portions in bearings in the body and have at the other end portions which protrude from the body, with a drilling tool on such protruding portion disposed above the pilot drilling tool and partially overlapping the the pilot tool in such a manner that in the course of drilling, there takes place a stepwise destruction of the bottom hole along its whole cross section, with the side shafts being imparted rotation by the drilling string through chain drives. With the body connected to the drilling string by means of bearings, there can no longer be effected any control over the rotation of the body since, with the drilling tools somewhat penetrated into the rock, or in case there is an obstacle (unevennes, large pieces of rock, etc.) in the bottom hole, the resistance offered to the transfer motion of the side drilling tools may exceed the torque arising on the body due to the reaction forces of the bottom, and the body will come to a stop, thus resulting in axial depending of the side drilling tool and discontinuation of the process of the hole sinking, although the pilot and side drilling tools will continue to rotate. Besides, the fact that each side shaft is provided with a chain drive which make the operation of the drilling tools dependent on one another, results in a more complicated design of the rig and less reliability in its operation.
It is an object of the present invention to eliminate the above-mentioned disadvantages.
SUMMARY OF THE INVENTION The present invention has as its object the provision of such a rig that, due to a different arrangement of the body and side shafts, is sufficiently reliable and more efficient in operation, and simpler to manufacture.
This object is accomplished in that in a rig according to the present invention, the body is rigidly connected with the drilling string, and the side shafts are mounted in the body loosely, whereby the side shafts can rotate about their axes irrespective of one another.
As a result of the present invention, there is provided a rig for drilling holes and shafts, which, as compared to conventional rigs, possesses a number of advantages.
Due to the fact that the body is rigidly connected with the drilling string and the side shafts are mounted loosely, the present rig operates irrespective of the value of deepening of the drilling tools into the rock and the state of the bottom hole thereby making it possible to vary within a wide range the drilling practices, as well as to ream the sections which were previously drilled. All this raises the efficiency of drilling and makes the operation more economical.
The following description of exemplary embodiments of the present invention is given with reference to the accompanying drawings, in which:
BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows a general view of the rig for drilling holes and shafts, with one row of side drilling tools, according to the invention, comma the view being partly in elevation and partly in section;
FIG. 2 shows a general view in elevation of the rig for drilling holes and shafts of a large diameter, with two rows of side drilling tools, according to the invention;
FIG. 3 is a section taken along line III-III of FIG. 2, the view looking in the direction of the arrows; and
FIG. 4 is a section taken along line lV--IV of FIG. 2, the view looking in the direction of the arrows.
DETAILED DESCRIPTION OF THE INVENTION As shown in FIG. 1, a rig for drilling holes and shafts comprises a drilling string 1, a body 2 with a central pipe 3, shafts 4 with bearings 5, weighting loads 6, a nut 7, a centrally disposed pilot drilling tool 8 and side drilling tools 9. The body 2 is rigidly connected with the drilling string 1 by means of the central pipe 3 which is either welded to the body, made integral therewith, or is connected thereto by any other method. Mounted on the body 2 in the bearings 5 by one of their end portions are the side shafts 4, so that each of the shafts 4 can rotate about its axis freely and independently of the other shafts.
Secured to the end portions of the shafts 4 protruding from the body 2, are drilling tools 9 mounted at one end the same level and radially displaced relative to the pilot drilling tool 8 which is arranged coaxially with respect to the drilling string 1, with the side drilling tools 9 partially overlapping the pilot drilling tool 8. Both single-cone, spherical or tapered, three-cone, multicone, and three-disc multi-disc, hits as well as blade or diamond drill bits and heads can be used as the drilling tools 8 and 9.
The present rig makes it possible to carry out diamond drilling of holes, for which purpose a diamond drill bit, for example, 212-214 mm in diameter can be used as a pilot drilling tool, and heads covered with diamonds as the side tools.
To drill holes of larger diameters equalling, for instance, 4200 mm, the rig may be constructed as shown in FIGS. 2,3, and 4, and comprise a drilling string la, a pilot drilling tool 10 of, for instance, a cutting type arranged centrally, and a body incorporating a central pipe 11 provided with a support plate 12 and three cross pieces l3, l4 and 15 carrying side shafts l6, l7 and 18, respectively, with tools (bits) 19, 20 and 21 radially displaced relative to the pilot drilling tool 10 which is disposed coaxially to the drilling string 1a; The side shafts l6, l7 and 18 are installed in the cross pieces 13, 14 and 15 in a manner similar to the shafts 4. The cross pieces l3, l4 and 15 are disposed one above another and are tightened to the support plate 12 by bolts 22 to form a monolithic system. The side tools are radially displaced from the tool 10 over various distances so that the tools 19 of the lower cross piece 13 partially overlap the pilot drilling tool 10; the tools 20 of the cross piece 14 partially overlap the tools 19, and the tools 21 of the cross piece partially overlap the tools 20. Thus, a stepwise destruction of the bottom hole over the entire cross section is provided.
This embodiment of the rig makes it possible to form a hole of a predetermined diameter either immediately, or by way of preliminary drilling of the hole by this rig with only one cross piece 13 (without using the cross pieces 14 and 15), to be followed by its reaming by means of the same rig using this time also the cross pieces 14 and 15.
The rig shown in FIG. 1 functions as follows:
The rig is rotated by means of the drilling string 1, and a pilot hole is drilled by the central tool 8. With the body 2 of the rig rigidly connected to the drilling string 1, the tools 9 connected to the side shafts 4 are imparted a transfer motion about the axis of the rig by the rotation of the drilling string 1. As the shafts 4 carrying the tools 9 can rotate freely, each of the side tools is imparted rotation independently of one another about its axis by contact with the bottom hole while drilling the rock along an annular area around the bore formed by the pilot tool.
When effecting drilling by means of the rig of the present invention, it is possible to use both direct and reverse circulation. When using the reverse circulation,
the cuttings are delivered into the drilling string through openings (not shown in the drawing) provided in the pilot tool.
The rig shown in FIGS. 2, 3 and 4 operates similarly and, therefore, its operation is not described in detail.
We claim:
1. A rig for the rotary drilling of holes and shafts, comprising a drilling string; a pilot drilling tool arranged coaxially relative to said drilling string; a body for said rig rigidly connected to said drilling string, side shafts carried by said body and being displaced radially relative to said pilot drilling tool; said side shafts having opposite end portions, bearings in said body in which one of the end portions of the side shafts is mounted to allow the side shafts to be capable of rotating freely about their axes, other end portions of the side shafts protruding from the body; and drilling tools secured to the protruding end portions of said side shafts and being disposed above said pilot drilling tool so that said side drilling tools partially overlap the pilot drilling tool.
2. The rig as claimed in claim 1 including a plurality of vertically spaced sets of side drilling tools, with the uppermost set of side tools overlapping the side drilling tools of the set therebelow.
Claims (2)
1. A rig for the rotary drilling of holes and shafts, comprising a drilling string; a pilot drilling tool arranged coaxially relative to said drilling string; a body for said rig rigidly connected to said drilling string, side shafts carried by said body and being displaced radially relative to said pilot drilling tool; said side shafts having opposite end portions, bearings in said body in which one of the end portions of the side shafts is mounted to allow the side shafts to be capable of rotating freely about their axes, other end portions of the side shafts protruding from the body; and drilling tools secured to the protruding end portions of said side shafts and being disposed above said pilot drilling tool so that said side drilling tools partially overlap the pilot drilling tool.
2. The rig as claimed in claim 1 including a plurality of vertically spaced sets of side drilling tools, with the uppermost set of side tools overlapping the side drilling tools of the set therebelow.
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US13652071A | 1971-04-22 | 1971-04-22 |
Publications (1)
Publication Number | Publication Date |
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US3743037A true US3743037A (en) | 1973-07-03 |
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Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
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US00136520A Expired - Lifetime US3743037A (en) | 1971-04-22 | 1971-04-22 | Rig for rotary drilling of holes and shafts |
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Cited By (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4185703A (en) * | 1976-06-18 | 1980-01-29 | Coyne & Bellier, Bureau d' ingenieurs Conseils | Apparatus for producing deep boreholes |
DE3109367A1 (en) * | 1981-03-12 | 1982-10-14 | Hydroc Gesteinsbohrtechnik GmbH, 5960 Olpe | DRILLING TOOL |
EP0087283A1 (en) * | 1982-02-20 | 1983-08-31 | Unicorn Industries Plc | Rotary drilling bits |
US20110023663A1 (en) * | 2009-07-31 | 2011-02-03 | Smith International, Inc. | Manufacturing methods for high shear roller cone bits |
US20110024197A1 (en) * | 2009-07-31 | 2011-02-03 | Smith International, Inc. | High shear roller cone drill bits |
US20110162893A1 (en) * | 2010-01-05 | 2011-07-07 | Smith International, Inc. | High-shear roller cone and pdc hybrid bit |
US9574405B2 (en) | 2005-09-21 | 2017-02-21 | Smith International, Inc. | Hybrid disc bit with optimized PDC cutter placement |
CN108500001A (en) * | 2018-03-19 | 2018-09-07 | 福建工程学院 | A kind of cement bunker library clearing machine spiral cutter head |
Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US759468A (en) * | 1902-11-14 | 1904-05-10 | Stirling Company | Boiler-tube cleaner. |
US2039551A (en) * | 1934-10-29 | 1936-05-05 | S R Bowen Company | Rotary bit |
US2208530A (en) * | 1938-02-03 | 1940-07-16 | Thompson Tool Company Inc | Rotary well drill |
US2370070A (en) * | 1942-05-08 | 1945-02-20 | H C Smith Oil Tool Co | Bit |
US2703698A (en) * | 1951-09-17 | 1955-03-08 | William J B Westerman | Counterboring rotary drill |
FR1278034A (en) * | 1960-10-24 | 1961-12-08 | Drill reducer |
-
1971
- 1971-04-22 US US00136520A patent/US3743037A/en not_active Expired - Lifetime
Patent Citations (6)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US759468A (en) * | 1902-11-14 | 1904-05-10 | Stirling Company | Boiler-tube cleaner. |
US2039551A (en) * | 1934-10-29 | 1936-05-05 | S R Bowen Company | Rotary bit |
US2208530A (en) * | 1938-02-03 | 1940-07-16 | Thompson Tool Company Inc | Rotary well drill |
US2370070A (en) * | 1942-05-08 | 1945-02-20 | H C Smith Oil Tool Co | Bit |
US2703698A (en) * | 1951-09-17 | 1955-03-08 | William J B Westerman | Counterboring rotary drill |
FR1278034A (en) * | 1960-10-24 | 1961-12-08 | Drill reducer |
Cited By (12)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US4185703A (en) * | 1976-06-18 | 1980-01-29 | Coyne & Bellier, Bureau d' ingenieurs Conseils | Apparatus for producing deep boreholes |
DE3109367A1 (en) * | 1981-03-12 | 1982-10-14 | Hydroc Gesteinsbohrtechnik GmbH, 5960 Olpe | DRILLING TOOL |
EP0087283A1 (en) * | 1982-02-20 | 1983-08-31 | Unicorn Industries Plc | Rotary drilling bits |
US9574405B2 (en) | 2005-09-21 | 2017-02-21 | Smith International, Inc. | Hybrid disc bit with optimized PDC cutter placement |
US20110023663A1 (en) * | 2009-07-31 | 2011-02-03 | Smith International, Inc. | Manufacturing methods for high shear roller cone bits |
US20110024197A1 (en) * | 2009-07-31 | 2011-02-03 | Smith International, Inc. | High shear roller cone drill bits |
US8672060B2 (en) | 2009-07-31 | 2014-03-18 | Smith International, Inc. | High shear roller cone drill bits |
US8955413B2 (en) * | 2009-07-31 | 2015-02-17 | Smith International, Inc. | Manufacturing methods for high shear roller cone bits |
US20110162893A1 (en) * | 2010-01-05 | 2011-07-07 | Smith International, Inc. | High-shear roller cone and pdc hybrid bit |
US9033069B2 (en) | 2010-01-05 | 2015-05-19 | Smith International, Inc. | High-shear roller cone and PDC hybrid bit |
CN108500001A (en) * | 2018-03-19 | 2018-09-07 | 福建工程学院 | A kind of cement bunker library clearing machine spiral cutter head |
CN108500001B (en) * | 2018-03-19 | 2020-12-01 | 福建工程学院 | Spiral tool bit of cement silo cleaning machine |
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