CN111119775B - Core tube that can be used to clean holes, retrieve gravel and take cores - Google Patents
Core tube that can be used to clean holes, retrieve gravel and take cores Download PDFInfo
- Publication number
- CN111119775B CN111119775B CN202010021349.9A CN202010021349A CN111119775B CN 111119775 B CN111119775 B CN 111119775B CN 202010021349 A CN202010021349 A CN 202010021349A CN 111119775 B CN111119775 B CN 111119775B
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- sand
- section
- core
- core tube
- bailing
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Classifications
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- 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
- E21B25/00—Apparatus for obtaining or removing undisturbed cores, e.g. core barrels or core extractors
-
- 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
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
-
- 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
- E21B27/00—Containers for collecting or depositing substances in boreholes or wells, e.g. bailers, baskets or buckets for collecting mud or sand; Drill bits with means for collecting substances, e.g. valve drill bits
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (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)
- Mechanical Engineering (AREA)
- Rigid Pipes And Flexible Pipes (AREA)
- Earth Drilling (AREA)
Abstract
本发明公开了既可清孔捞取砂砾石又可取芯的岩芯管，包括捞砂段、取芯段和岩芯管连接段；捞砂段内设有内腔管壁形成双层结构；内腔管壁的上端与岩芯管接头连接；捞砂段顶部外形呈弧线形流线；捞砂段靠近上端的外层管壁设有一对进砂口；捞砂段靠近下端设有若干泄水孔；岩芯管连接段的上部设有内腔管壁形成双层结构，下部为单层结构；岩芯管连接段的中部设有环形的隔砂板形成台梯形结构；捞砂段双层结构间的间隙，以及岩芯管连接段上部的双层结构间的间隙与隔砂板围成一个上部开口的储砂室；岩芯管连接段的下端与取芯段连接，取芯段的下端设有钻头。本发明除具备钻进取芯功能外，还具备在各种砂砾石以及风化的岩石碎屑层中捞取砂砾石的功能。
The invention discloses a core tube that can be used for hole cleaning, sand and gravel scooping and core extraction, including a sand scooping section, a core extraction section and a core tube connection section; the sand scooping section is provided with an inner cavity tube wall to form a double-layer structure; the upper end of the inner cavity tube wall is connected to the core tube joint; the top of the sand scooping section is in an arc-shaped streamline; the outer layer tube wall near the upper end of the sand scooping section is provided with a pair of sand inlets; the sand scooping section is provided with a plurality of drainage holes near the lower end; the upper part of the core tube connection section is provided with an inner cavity tube wall to form a double-layer structure, and the lower part is a single-layer structure; the middle part of the core tube connection section is provided with an annular sand isolation plate to form a step-shaped structure; the gap between the double-layer structures of the sand scooping section and the gap between the double-layer structures at the upper part of the core tube connection section and the sand isolation plate form a sand storage chamber with an upper opening; the lower end of the core tube connection section is connected to the core extraction section, and a drill bit is provided at the lower end of the core extraction section. In addition to the drilling and coring functions, the invention also has the function of scooping sand and gravel from various sand and gravel and weathered rock debris layers.
Description
Technical Field
The invention relates to the technical field of geological drilling, in particular to a core barrel capable of clearing Kong Laoqu sand gravel and coring.
Background
In geotechnical engineering investigation, medium coarse sand gravel, cohesive soil sand gravel and weathered rock debris layers are frequently encountered, coarse particle components such as medium coarse sand gravel, weathered rock debris and the like are often unable to be discharged along with circulating slurry in the process of circularly drilling and clearing holes, so that sediment in holes is increased, the clearing holes are not clean, core samples adopted by the rock core tubes disturb the sediment, so that fresh core samples are often rarely adopted, accurate division of stratum layers is affected, accuracy and reliability of in-situ test data (standard penetration test and heavy dynamic penetration test) of the coarse particle soil layers are also affected, in-situ test data (standard penetration test and heavy dynamic penetration test) are critical to engineering mechanical properties of the soil layers, the problem is difficult to solve by the conventional exploration technology and equipment, the problem is difficult to solve, the existing special sand device is adopted, the slurry is firstly used for carrying out the whirl drilling on the core tubes, and then the core tubes are required to be cleared, and then the drilling is carried out, and the risk is often increased, and the risk is not wasted when drilling is increased.
In the prior art, the following solutions for drilling and cleaning holes by using the sand bailing equipment are available:
The Chinese patent of invention with publication number CN 103573202A discloses a drilling sand-bailing mechanism and a drilling tool, the sand-bailing mechanism is annularly arranged outside a drill rod and comprises a sand-bailing barrel which is arranged outside the drill rod and axially arranged along the drill rod, the sand-bailing barrel comprises a closed end connected with the drill rod and an annular side wall which is annularly arranged outside the drill rod and is provided with a gap with the drill rod to form a sand filling space, the upper end of the side wall is provided with an inclined opening communicated with the sand filling space, the side wall is respectively provided with a plurality of sand inlet holes and a plurality of water outlet holes communicated with the sand filling space, and a plurality of sand inlet holes are respectively arranged above the water outlet holes along the direction of the drill rod from top to bottom.
The Chinese patent publication No. CN 207048709U discloses a reverse circulation while-drilling sand dredger, which is connected with the part of the reverse circulation drilling tool structure close to the drill bit, the lower part is connected with the drill collar or the drill bit, and the upper part is connected with the single-wall drilling tool to form a part of the reverse circulation drilling tool, thereby having the functions of sand setting, sand dredging and anti-blocking.
The Chinese patent publication No. CN 204492724U discloses a sand-bailing device, which comprises a milling shoe, a drill bit, a mandrel, a helical blade and a sand storage cylinder, wherein the milling shoe is connected with the sand storage cylinder, the drill bit is fixedly arranged in the milling shoe, the drill bit is fixedly connected with the mandrel, the helical blade is arranged on the mandrel, and the mandrel and the helical blade form a helical conveying mechanism for conveying sand setting to the sand storage cylinder, so that the problem of sand-bailing of a low-pressure leakage oil-gas well is solved.
The Chinese patent publication No. CN 205876248U discloses a valve clack type bailing cylinder, wherein a negative pressure valve is arranged in the valve clack type bailing cylinder, and once sand is leaked from the outside of the body of the bailing cylinder, the valve clack is closed along with the leakage of the sand.
According to analysis of the four schemes, although the utility model patent with the publication number CN 103573202A is mainly aimed at geotechnical engineering investigation and geological investigation, drilling and sticking are easy to be carried out when the sand is fished due to the transverse oblique opening of the sand bailing barrel, gaps are formed between the sand bailing barrel and between the sand bailing barrel and the rock core pipe, large-particle gravel or rock fragments are easy to deposit between the gaps to cause equipment sticking, drilling and burying are easy to be carried out, great limitation and construction risks exist in actual use, the utility model patent with the publication number CN 207048709U is mainly applied to sand setting, sand bailing and anti-blocking on drilling, normal circulation is generally adopted in geotechnical engineering investigation, the utility model patent with the publication number CN 204492724U is applied to sand bailing problem treatment of oil and gas wells on oil fields, no back slurry is adopted, and drilling hole forming function is not provided, and the utility model patent with the publication number CN 205876248U is used for solving sand setting problem of oil well shafts and sand burying problem of downhole tools and no hole forming function.
In addition, other non-exemplified utility models or utility models are basically used for the sand-pumping service of oil extraction wells in oil fields, and are not suitable or practical in geotechnical engineering investigation and geological investigation.
Disclosure of Invention
In view of the above-mentioned defect of the prior art, the invention provides a core barrel capable of clearing Kong Laoqu sand gravel and coring, which not only has the conventional core barrel drilling coring function, but also has the function of taking out sand gravel and rock fragments in the drilling process of medium coarse sand gravel, cohesive soil sand gravel and weathered rock fragment layers, thereby playing a more thorough hole clearing role, and greatly solving the problems that coarse particle sand gravel and rock fragments caused by the conventional drilling process in the medium coarse sand gravel, cohesive soil sand gravel and weathered rock fragment layers are difficult to collect due to the fact that the specific gravity is large and cannot be circulated back along with slurry, so that the sediments are thicker, and the accurate division of soil layer boundaries and the accuracy and reliability of in-situ test data are affected.
In order to achieve the purpose, the invention discloses a core pipe capable of clearing Kong Laoqu sand gravel and coring, wherein the upper end of the core pipe is connected with a drill rod female joint through a core pipe joint, the lower end of the core pipe is connected with a drill bit, and the upper end of the drill rod female joint is connected with a drill rod.
The core barrel comprises a sand-bailing section, a coring section and a core barrel connecting section for connecting the sand-bailing section and the coring section;
An inner cavity pipe wall is arranged in the sand bailing section to form a double-layer structure, and the upper end of the inner cavity pipe wall is connected with the core barrel joint;
The outer layer pipe wall of the sand-bailing section close to the upper end is symmetrically provided with a pair of sand inlets extending along the length direction;
the outer diameter of the core pipe connecting section is the same as the outer diameter of the sand bailing section and the outer diameter of the coring section, the upper part is provided with an inner cavity pipe wall to form a double-layer structure, and the lower part is of a single-layer structure;
The middle part of the core tube connecting section is provided with an annular sand separation plate to form a trapezoid structure, the outer diameter of the sand separation plate is matched with the outer layer tube wall of the sand-bailing section and the outer layer tube wall at the upper part of the core tube connecting section, and the inner diameter of the sand separation plate is matched with the inner cavity tube wall of the sand-bailing section and the inner cavity tube wall at the upper part of the core tube connecting section;
The gap between the double-layer structures of the sand bailing section, the gap between the double-layer structures at the upper part of the core tube connecting section and the sand separating plate enclose a sand storage chamber with an opening at the side surface at the upper part;
the lower end of the core tube connecting section is connected with the coring section, and the drill bit is arranged at the lower end of the coring section.
Preferably, the plurality of water discharge holes are provided with at least three layers along the length direction of the sand bailing section, and the plurality of water discharge holes of each layer are uniformly distributed around the axis of the sand bailing section.
Preferably, the upper end and the lower end of the core pipe connecting section are respectively connected with the sand fishing section and the coring section in a threaded connection mode, the inner cavity pipe wall of the core pipe connecting section is connected with the inner cavity pipe wall of the sand fishing section in a trapezoidal splicing mode, and the lower part of the core pipe coring section can be in threaded connection with a drill bit.
More preferably, the threaded connection mode is a flat thread.
Preferably, the core pipe is 4.3m long, the sand-bailing section is 2.0m long, the core pipe connecting section is 20cm long, the core section is 2.0m long, the size of each sand inlet is 30mm x 300mm, the size of the inner cavity pipe wall is 20mm in inner diameter and 3mm in wall thickness, and the sand storage chamber is of a ring column-shaped structure with the width of 36mm and the length of 1.7 m.
The invention has the beneficial effects that:
The invention not only can drill by mud wall protection rotary clear hole, but also can drill by rotary drilling without flushing liquid after clear hole is clear, and the arc streamline at the top of the novel core pipe sand bailing section can effectively avoid the accident of drilling jamming or burying when the sand gravel or weathered rock fragments are bailed.
After gravel or rock fragments are stored in the sand-bailing section at the upper part of the rock core pipe, if the sand-bailing section is blocked or jammed, the sand-bailing section at the upper part of the rock core pipe is only required to be lifted, coarse grain sediment can be conveniently fished out through lightly shaking and hammer flicking, the purposes of Kong Ganjing, thoroughly and conveniently are achieved, meanwhile, the core sample is directly taken by the core-bailing section at the lower part of the rock core pipe, the exploration efficiency is improved, a solid foundation is laid for the accuracy and reliability of in-situ test data, and the method has wide prospects in geotechnical engineering investigation and geological investigation.
The conception, specific structure, and technical effects of the present invention will be further described with reference to the accompanying drawings to fully understand the objects, features, and effects of the present invention.
Drawings
Fig. 1 shows a schematic structural diagram of an embodiment of the present invention.
FIG. 2 is a schematic diagram showing the cross-sectional structure of the AA in FIG. 1 according to the present invention.
Fig. 3 is a schematic diagram showing a cross-sectional structure at BB in fig. 1 according to the present invention.
FIG. 4 is a schematic view showing a cross-sectional structure of the sand screen of FIG. 1 at CC according to the present invention.
Fig. 5 is an enlarged schematic view of a section of the lower part of the bailing segment and the core tube according to an embodiment of the present invention.
Fig. 6 shows a schematic view of the structure of an embodiment of the present invention disposed in a borehole.
Detailed Description
As shown in fig. 1 to 6, a core barrel which can remove Kong Laoqu sand gravel and core is arranged in the drill hole 11, the outer diameter of the core barrel is smaller than that of the drill hole 11, and a gap 12 is formed.
The upper end of the core barrel is connected with the drill rod female joint 2 through the core barrel joint 3, the lower end is connected with the drill bit 10, and the upper end of the drill rod female joint 2 is connected with the drill rod 1.
The rock core pipe comprises a sand-bailing section 4, a coring section 9 and a rock core pipe connecting section 8 for connecting the sand-bailing section 4 and the coring section 9;
the upper end of the inner cavity pipe wall is connected with the core pipe joint 3;
the outer layer pipe wall of the sand bailing section 4 close to the upper end is symmetrically provided with a pair of sand inlets 5 extending along the length direction, and the outer layer pipe wall of the sand bailing section 4 close to the lower end is provided with a plurality of water discharge holes 7;
the outer diameter of the core pipe connecting section 8 is the same as the outer diameters of the sand bailing section 4 and the coring section 9, the upper part is provided with an inner cavity pipe wall to form a double-layer structure, and the lower part is of a single-layer structure;
the middle part of the core tube connecting section 8 is provided with an annular sand separation plate to form a trapezoid structure, the outer diameter of the sand separation plate is matched with the outer layer tube wall of the sand bailing section 4 and the outer layer tube wall at the upper part of the core tube connecting section 8, and the inner diameter of the sand separation plate is matched with the inner cavity tube wall of the sand bailing section 4 and the inner cavity tube wall at the upper part of the core tube connecting section 8;
The gap between the double-layer structures of the sand bailing section 4 and the gap between the double-layer structures at the upper part of the core tube connecting section 8 and the sand separating plate enclose a sand storage chamber 6 with an opening at the side surface at the upper part;
The lower extreme of core pipe linkage segment 8 is connected with coring section 9, and the lower extreme of coring section 9 is equipped with drill bit 10.
The principle of the invention is as follows:
The core tube connecting section 8 is seamlessly connected with the sand-bailing section 4 and the coring section 9 of the core tube, and the sand-bailing section on the upper part of the core tube forms a closed sand storage chamber 6, and flushing fluid in the sand storage chamber 6 is discharged through a plurality of water discharge holes 7.
The coring section 9 is similar to a conventional core barrel and is seamlessly connected with the bailing section 4 through the core barrel connecting section 8.
According to the invention, kong Laoqu sand gravel can be cleaned and core-extracted, as shown in fig. 6, in the process of rotary drilling through a mud guard during drilling, flushing fluid carrying suspended sand gravel or weathered rock fragments enters the sand storage chamber 6 through the sand inlet 5 of the sand-extracting section 4 in the process of upward returning of a gap 12 between a drilling hole 11 and a rock core pipe, and the flushing fluid is discharged along the water discharge hole 7, so that the purpose of cleaning the hole and extracting sand is achieved, and the purpose of directly taking core samples can be achieved by the rock core pipe with the lower part in seamless connection.
After the core pipe is pulled out from the drill hole 11, the core sample is pushed out or shaken by water pressure, a light hammer is taken out from the core pipe and placed in the core box, the sand-bailing section 4, the coring section 9 and the core pipe connecting section 8 are conveniently detached through chain tongs, the sand-bailing section 4 is lifted, the sand gravel, weathered rock fragments and the like which are fished can fall freely, and if the core sample is blocked, coarse grain sediment which is fished can be conveniently poured out through gently shaking and hammer flicking.
In some embodiments, the plurality of drainage holes 7 are provided with at least three layers along the length direction of the bailing segment 4, and the plurality of drainage holes 7 of each layer are uniformly distributed around the axis of the bailing segment 4.
In some embodiments, the upper end and the lower end of the core tube connecting section 8 are respectively connected with the sand-bailing section 4 and the coring section 9 in a threaded connection manner, the inner cavity wall of the core tube connecting section 8 is connected with the inner cavity wall of the sand-bailing section 4 in a trapezoidal splicing manner, and the lower part of the core tube coring section 9 can be in threaded connection with the drill bit 10.
In some embodiments, the threaded connection is a flat thread.
In some embodiments, the core pipe is 4.3m long, the sand bailing section 4 is 2.0m long, the core pipe connecting section 8 is 20cm long, the core section 9 is 2.0m long, the size of each sand inlet 5 is 30mm x 300mm, the size of the inner cavity pipe wall is 20mm in inner diameter and 3mm in wall thickness, and the sand storage chamber 6 is of a ring column-shaped structure with the width of 36mm and the length of 1.7 m.
The foregoing describes in detail preferred embodiments of the present invention. It should be understood that numerous modifications and variations can be made in accordance with the concepts of the invention by one of ordinary skill in the art without undue burden. Therefore, all technical solutions which can be obtained by logic analysis, reasoning or limited experiments based on the prior art by the person skilled in the art according to the inventive concept shall be within the scope of protection defined by the claims.
Claims (4)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010021349.9A CN111119775B (en) | 2020-01-09 | 2020-01-09 | Core tube that can be used to clean holes, retrieve gravel and take cores |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010021349.9A CN111119775B (en) | 2020-01-09 | 2020-01-09 | Core tube that can be used to clean holes, retrieve gravel and take cores |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN111119775A CN111119775A (en) | 2020-05-08 |
| CN111119775B true CN111119775B (en) | 2025-02-11 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202010021349.9A Active CN111119775B (en) | 2020-01-09 | 2020-01-09 | Core tube that can be used to clean holes, retrieve gravel and take cores |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN111119775B (en) |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101037859A (en) * | 2006-03-13 | 2007-09-19 | 中交第三航务工程勘察设计院有限公司 | Double-tubes single-action valve type coring earth borrowing device |
| CN202832330U (en) * | 2012-07-24 | 2013-03-27 | 深圳市工勘岩土工程有限公司 | Sand mechanism and drilling tool |
| CN211598581U (en) * | 2020-01-09 | 2020-09-29 | 上海市城市建设设计研究总院（集团）有限公司 | Novel rock core pipe capable of clearing hole, fishing sand and gravel and taking core |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| SU759699A1 (en) * | 1978-07-18 | 1980-08-30 | Sp K B N Proizv Obedineniya Ge | Removable core-reciever fisher |
| RU2017931C1 (en) * | 1990-09-21 | 1994-08-15 | Сургутское отделение Западно-Сибирского научно-исследовательского и проектно-конструкторского института технологии глубокого разведочного бурения | Device for well drilling with retrievable core receiver |
| JP3983345B2 (en) * | 1997-07-01 | 2007-09-26 | 株式会社キャプティ | Sediment collector and sediment collection method |
| CN103573202A (en) * | 2012-07-24 | 2014-02-12 | 深圳市工勘岩土工程有限公司 | Sand bailing mechanism and drilling tool |
| CN203894076U (en) * | 2014-05-07 | 2014-10-22 | 青海省电力设计院 | Desert-region fixed-point sand sampler |
| CN203981430U (en) * | 2014-07-03 | 2014-12-03 | 宁波浙东地质器材制造有限责任公司 | Exploration sand extractor |
| RU178080U1 (en) * | 2017-12-25 | 2018-03-22 | Федеральное государственное автономное образовательное учреждение высшего образования "Северо-Восточный федеральный университет имени М.К.Аммосова" | Core drill for large diameter wells |
-
2020
- 2020-01-09 CN CN202010021349.9A patent/CN111119775B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101037859A (en) * | 2006-03-13 | 2007-09-19 | 中交第三航务工程勘察设计院有限公司 | Double-tubes single-action valve type coring earth borrowing device |
| CN202832330U (en) * | 2012-07-24 | 2013-03-27 | 深圳市工勘岩土工程有限公司 | Sand mechanism and drilling tool |
| CN211598581U (en) * | 2020-01-09 | 2020-09-29 | 上海市城市建设设计研究总院（集团）有限公司 | Novel rock core pipe capable of clearing hole, fishing sand and gravel and taking core |
Also Published As
| Publication number | Publication date |
|---|---|
| CN111119775A (en) | 2020-05-08 |
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