CN118008179A - Screw motor coring structure and coring technology of directional drilling deflecting section thereof - Google Patents
Screw motor coring structure and coring technology of directional drilling deflecting section thereof Download PDFInfo
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- CN118008179A CN118008179A CN202410098719.7A CN202410098719A CN118008179A CN 118008179 A CN118008179 A CN 118008179A CN 202410098719 A CN202410098719 A CN 202410098719A CN 118008179 A CN118008179 A CN 118008179A
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- 238000005553 drilling Methods 0.000 title claims abstract description 236
- 238000005516 engineering process Methods 0.000 title abstract description 7
- 238000000034 method Methods 0.000 claims abstract description 25
- 238000013461 design Methods 0.000 claims abstract description 12
- 239000000523 sample Substances 0.000 claims description 26
- 238000005259 measurement Methods 0.000 claims description 23
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 239000011435 rock Substances 0.000 claims description 7
- 230000005540 biological transmission Effects 0.000 claims description 5
- 239000002002 slurry Substances 0.000 claims description 4
- 229910003460 diamond Inorganic materials 0.000 description 4
- 239000010432 diamond Substances 0.000 description 4
- 238000012546 transfer Methods 0.000 description 4
- 239000003638 chemical reducing agent Substances 0.000 description 3
- 239000002131 composite material Substances 0.000 description 3
- 238000011835 investigation Methods 0.000 description 3
- 230000000712 assembly Effects 0.000 description 2
- 238000000429 assembly Methods 0.000 description 2
- 238000010276 construction Methods 0.000 description 2
- 238000011161 development Methods 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
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Abstract
The invention discloses a screw motor coring structure, and relates to the field of directional drilling and coring drilling processes. The drilling machine comprises a directional drilling rod, a guiding system, a screw drilling tool, a core barrel and a coring bit; the screw drilling tool is a bent screw drilling tool. The invention can make directional deflecting and coring drilling simultaneously, namely the deflecting drilling process is also the coring drilling process, which can ensure that the drilling track extends according to the design track, and can also ensure the core taking rate without being carried out separately. The invention also relates to a coring technology of the directional drilling deflecting section of the screw motor coring structure.
Description
Technical Field
The invention relates to the field of directional drilling and coring drilling processes, in particular to a screw motor coring structure and a coring technology of a directional drilling deflecting section of the screw motor coring structure.
Background
At present, most of coring techniques applied to directional drilling are back-drilling coring techniques, and drilling tool assemblies applied to directional deflecting drilling and coring drilling are respectively two sets of relatively independent drilling tool assemblies.
When directional deflecting drilling is performed, the front end of the drill rod is sequentially connected with a screw drilling tool and a directional drill bit, and full-section broken drilling is adopted in the drilling process; when the core drilling is performed, a conventional hollow drill rod is adopted, the front end of the hollow drill rod is connected with a core barrel and a core drill bit, and a core can be taken in the core drilling process, but the drilling track cannot be controlled in real time.
In general, in order to take a core, directional drilling adopts a method of alternately performing deflecting drilling and coring drilling; the deflecting drilling is full-section crushing drilling, a core is not adopted, after the deflecting drilling is finished, the screw drilling tool is replaced by a coring drilling tool by lifting the drilling tool, the coring drilling is carried out, and the deflecting is not carried out in the process of the deflecting drilling is finished; in some engineering investigation projects with high requirements on core taking, the method cannot accurately control drilling tracks, cannot ensure high core taking rate, reduces the quality of results of engineering investigation, and also can be used for safely burying hidden danger for the construction of subsequent engineering construction projects.
Therefore, in order to solve the problem that the core cannot be simultaneously taken in the process of drilling the deflecting drill, it is necessary to develop a screw motor coring structure and a coring technology of a directional drilling deflecting section thereof.
Disclosure of Invention
A first object of the present invention is to overcome the above-mentioned drawbacks of the related art, and to provide a screw motor coring structure.
A second object of the present invention is to provide a coring technique for a directional drilling whipstock of such a screw motor coring structure
In order to achieve the first object, the technical scheme of the invention is as follows: a screw motor coring structure, characterized in that: the drilling device comprises a directional drill rod, a guide system connected with the directional drill rod, a screw drilling tool connected with the guide system, a core barrel connected with a transmission shaft of the screw drilling tool, and a coring bit connected with the core barrel;
The screw drilling tool is a curved screw drilling tool.
In the above technical scheme, the guide system includes non-magnetic drill rod, probe outer tube, lower non-magnetic drill rod and measurement probe, go up non-magnetic drill rod and directional drilling rod and be connected, lower non-magnetic drill rod is connected with the screw rod drilling tool, probe outer tube one end is connected with last non-magnetic drill rod, the other end is connected with lower non-magnetic drill rod, the measurement probe is located probe outer tube, the measurement probe is connected with the cable, the cable stretches out directional drilling rod along last non-magnetic drill rod.
In the technical scheme, the angle range of the elbow of the screw drilling tool is 0-1.5 degrees; the length range of the core tube is 0.5m-3.0m.
In the technical scheme, the larger the angle of the elbow of the screw drilling tool is, the shorter the length of the core barrel is; the longer the core barrel length is, the smaller the angle of the elbow of the screw drilling tool is.
In the technical scheme, the core barrel is connected with the transmission shaft through the reducer union.
In order to achieve the second object, the technical scheme of the invention is as follows:
The coring technique of the directional drilling deflecting section of the screw motor coring structure is characterized by comprising the following steps of:
Step 1: selecting a proper drilling tool assembly; after the directional drilling finishes drilling of the inclined hole section along the inclination angle of the opening and reaches the starting point of the deflecting section, lifting the drilling to the ground surface, and replacing a drilling tool assembly aiming at the deflecting section;
Step 2: the method comprises the steps of sequentially connecting an upper nonmagnetic drill rod, a measuring probe tube and a lower nonmagnetic drill rod in a directional drill rod, sequentially installing a selected screw drilling tool, a core barrel and a coring bit at the front end of the drilling tool, and replacing the directional bit at the front end of the screw drilling tool by the core barrel and the coring bit during conventional directional deflecting;
Step 3: after the drilling tool assembly is installed, connecting a measuring system, resetting and correcting the tool face angle of the drilling tool at an orifice, and drilling down to the bottom of a hole;
step 4: before driller, connecting a measurement while drilling joint behind a drill rod, and measuring a drilling track;
Step 5: calculating the tool face angle of the secondary screw drilling tool according to the drilling design track data, turning the power head of the drilling machine clockwise, simultaneously observing the graphic interface of the measurement while drilling system, and turning the drilling tool to the calculated tool face;
Step 6: removing a measurement while drilling joint behind a drill rod, connecting a water joint, starting a slurry pump, adjusting drilling parameters, performing sliding directional drilling with proper weight on bit and pump amount, enabling a drilling track to extend along the direction of the current tool face, and enabling a core to enter a core barrel by breaking a rock stratum at the front end of a core bit;
Step 7: and (3) drilling forwards until the core is full of the core, removing the water joint, connecting the water joint with the measurement while drilling system again, measuring data of the current measuring point, acquiring drilling track data, and comparing the drilling track data with drilling design track data.
Step 8: after the drilling track data comparison is completed, the drilling tool in the hole is lifted, the core barrel at the front end of the screw drilling tool is disassembled, the coring bit is disassembled, and the core in the core barrel is taken out, so that the secondary directional deflecting and coring drilling are completed.
Step 9: and (3) repeating the steps 2-8, gradually drilling until the directional drilling deflecting section is completely completed, and drilling into a horizontal hole section where the tunnel buries.
Compared with the prior art, the invention has the following advantages:
1) The invention can make directional deflecting and coring drilling simultaneously, namely the deflecting drilling process is also the coring drilling process, which can ensure that the drilling track extends according to the design track, and can also ensure the core taking rate without being carried out separately.
2) Compared with the existing directional drilling technology and coring technology, the full-hole coring method can realize full-hole coring in the drilling process, improves the accuracy degree of drilling tracks and the core sampling rate, and improves the efficiency and the accuracy of reconnaissance work.
Drawings
Fig. 1 is a schematic structural view of the present invention.
The device comprises a 1-directional drill rod, a 2-guiding system, a 21-upper nonmagnetic drill rod, a 22-probe outer tube, a 23-lower nonmagnetic drill rod, a 24-measurement probe, a 241-cable, a 3-screw drilling tool, a 31-transmission shaft, a 4-core barrel, a 41-reducer union, a 5-core bit and a 6-directional bit.
Detailed Description
The following detailed description of the invention is, therefore, not to be taken in a limiting sense, but is made merely by way of example. While the advantages of the invention will become apparent and readily appreciated by reference to the following description.
As can be seen with reference to the accompanying drawings: a screw motor coring structure, characterized in that: the drilling tool comprises a directional drilling rod 1, a guide system 2 connected with the directional drilling rod 1, a screw drilling tool 3 connected with the guide system 2, a core barrel 4 connected with a transmission shaft 31 of the screw drilling tool 3 and a coring bit 5 connected with the core barrel 4;
The screw drilling tool 3 is a curved screw drilling tool.
The guiding system 2 comprises an upper nonmagnetic drill rod 21, a probe outer tube 22, a lower nonmagnetic drill rod 23 and a measuring probe 24, wherein the upper nonmagnetic drill rod 21 is connected with the directional drill rod 1, the lower nonmagnetic drill rod 23 is connected with the screw drilling tool 3, one end of the probe outer tube 22 is connected with the upper nonmagnetic drill rod 21, the other end of the probe outer tube is connected with the lower nonmagnetic drill rod 23, the measuring probe 24 is positioned in the probe outer tube 22, the measuring probe 24 is connected with a cable 241, and the cable 241 extends out of the directional drill rod 1 along the upper nonmagnetic drill rod 21.
The angle range of the elbow of the screw drilling tool 3 is 0-1.5 degrees, and special manufacturing is not needed; the length of the core barrel 4 ranges from 0.5m to 3.0m, and different lengths are required to be selected according to the screw drilling tool 3 and stratum conditions.
The larger the angle of the elbow of the screw drilling tool 3 is, the shorter the length of the core barrel 4 is; conversely, the longer the core barrel 4, the smaller the angle of the bend of the screw drilling tool 3.
The core barrel 4 is connected to the drive shaft 31 via a reducer union 41.
The coring technique of the directional drilling deflecting section of the screw motor coring structure is characterized by comprising the following steps of:
Step 1: selecting a proper drilling tool assembly; after the directional drilling finishes drilling of the inclined hole section along the inclination angle of the opening and reaches the starting point of the deflecting section, lifting the drilling to the ground surface, and replacing a drilling tool assembly aiming at the deflecting section;
Step 2: the method comprises the steps of sequentially connecting an upper nonmagnetic drill rod 21, a measuring probe 24 and a lower nonmagnetic drill rod 23 in the directional drill rod 1, sequentially installing a selected screw drilling tool 3, a core barrel 4 and a coring bit 5 at the front end of the drilling tool, and replacing the directional bit 6 at the front end of the screw drilling tool by the core barrel 4 and the coring bit 5 during conventional directional deflecting;
Step 3: after the drilling tool assembly is installed, connecting a measuring system, resetting and correcting the tool face angle of the drilling tool at an orifice, and drilling down to the bottom of a hole;
step 4: before driller, connecting a measurement while drilling joint behind a drill rod, and measuring a drilling track;
Step 5: calculating the tool face angle of the secondary screw drilling tool 3 according to the drilling design track data, turning the power head of the drilling machine clockwise, observing the graphic interface of the measurement while drilling system, and turning the drilling tool to the calculated tool face;
Step 6: removing a measurement while drilling joint behind a drill rod, connecting a water joint, starting a slurry pump, adjusting drilling parameters, performing sliding directional drilling with proper weight on bit and pump amount, enabling a drilling track to extend along the current tool face direction, and enabling a core bit 5 to break a rock stratum at the front end and enter a core barrel 4;
Step 7: and after the core is fully filled with the core pipe 4, the water joint is removed, the measurement while drilling system is connected again, the data measurement is carried out on the current measuring point, the drilling track data is obtained, and the drilling track data is compared with the drilling design track data.
Step 8: after the drilling track data comparison is completed, the drilling tool in the hole is put forward, the core barrel 4 at the front end of the screw drilling tool 3 is disassembled, the coring bit 5 is disassembled, the core in the core barrel 4 is taken out, and the directional deflecting and coring drilling of the round is completed.
Step 9: and (3) repeating the steps 2-8, gradually drilling until the directional drilling deflecting section is completely completed, and drilling into a horizontal hole section where the tunnel buries.
In actual use, the core barrel 4 can be a single-pipe core barrel, a double-pipe core barrel, a three-layer pipe and the like; the core drill 5 is selected according to the core tube 4 and stratum conditions, and can be selected from a diamond impregnated drill, a diamond surface insert drill, a diamond composite bit and an electroplated drill. When the directional drilling reaches the starting point of the deflecting section, lifting the drilling to the orifice to replace the drilling tool assembly; the screw drilling tool 3 with a proper angle and the core barrel 4 with a proper length are selected according to the maximum dog leg degree of the drilling design.
Examples
The invention is further invented below in connection with the example of directional drilling of a survey project of a water conveyance tunnel, but the invention is not limited to the following example.
In order to find out the stratum lithology and geological structure, karst phenomenon and development degree, rock mass permeability, development fault zone scale, engineering geological characteristics and the like of the surrounding rock of the tunnel, compound directional drilling holes are arranged for investigation; the composite directional drilling design is used for drilling inclined hole sections by forming holes at an inclined angle of-25 degrees, then entering a horizontal hole section where the embedded depth of the tunnel is located through a track transfer section with a track transfer curvature of 1 degree/3 m, and finally entering a final inclined hole section through the track transfer section with the track transfer curvature of 1 degree/3 m.
The borehole requires Kong Quxin for which the invention is applied to the track section of the borehole.
A coring technique for a directional drilling deflecting section of a screw motor coring structure, comprising the steps of:
Step 1: selecting a proper drilling tool assembly; after the directional drilling finishes drilling of the inclined hole section along the inclination angle of the opening and reaches the starting point of the deflecting section, lifting the drilling to the ground surface, and replacing a drilling tool assembly aiming at the deflecting section; according to the designed drilling track and stratum condition, a screw drilling tool 3 with the angle of 1.25 degrees is selected, a core barrel 4 with the length of 1m, 1.5m, 2m and 3m unequal is adopted, the core barrel 4 is flexibly replaced according to the actual stratum condition and the drilling track, and a diamond composite sheet drill with the diameter of phi 110mm is adopted as the coring drill 5.
Step 2: the method comprises the steps of sequentially connecting an upper nonmagnetic drill rod 21, a measuring probe 24 and a lower nonmagnetic drill rod 23 in the directional drill rod 1, sequentially installing a selected screw drilling tool 3, a core barrel 4 and a coring bit 5 at the front end of the drilling tool, and replacing the directional bit 6 at the front end of the screw drilling tool by the core barrel 4 and the coring bit 5 during conventional directional deflecting;
Step 3: after the drilling tool assembly is installed, connecting a measuring system, resetting and correcting the tool face angle of the drilling tool at an orifice, and drilling down to the bottom of a hole;
step 4: before driller, connecting a measurement while drilling joint behind a drill rod, and measuring a drilling track;
step 5: according to the drilling design track data, calculating the tool face angle of the secondary screw drilling tool 3, turning the power head of the drilling machine clockwise, simultaneously observing the graphic interface of the measurement while drilling system, and turning the drilling tool to the calculated tool face.
Step 6: the measurement while drilling joint at the rear of the drill rod is removed, the water joint is connected, a slurry pump is started, drilling parameters are adjusted, sliding directional drilling is carried out with proper weight on bit and pump amount, a drilling track extends along the direction of the current tool face, and meanwhile, the coring bit 5 breaks the rock stratum at the front end, so that a rock core enters the core barrel 4.
Step 7: and after the core is fully filled with the core pipe 4, the water joint is removed, the measurement while drilling system is connected again, the data measurement is carried out on the current measuring point, the drilling track data is obtained, and the drilling track data is compared with the drilling design track data.
Step 8: after the drilling track data comparison is completed, the drilling tool in the hole is put forward, the core barrel 4 at the front end of the screw drilling tool 3 is disassembled, the coring bit 5 is disassembled, the core in the core barrel 4 is taken out, and the directional deflecting and coring drilling of the round is completed.
Step 9: and (3) repeating the steps 2-8, gradually drilling until the directional drilling deflecting section is completely completed, and drilling into a horizontal hole section where the tunnel buries.
Other non-illustrated parts are known in the art.
Claims (6)
1. A screw motor coring structure, characterized in that: the drilling device comprises a directional drilling rod (1), a guide system (2) connected with the directional drilling rod (1), a screw drilling tool (3) connected with the guide system (2), a core barrel (4) connected with a transmission shaft (31) of the screw drilling tool (3) and a coring bit (5) connected with the core barrel (4);
the screw drilling tool (3) is a bent screw drilling tool.
2. A screw motor coring structure according to claim 1, wherein: the guiding system (2) comprises an upper nonmagnetic drill rod (21), a probe outer tube (22), a lower nonmagnetic drill rod (23) and a measuring probe tube (24), wherein the upper nonmagnetic drill rod (21) is connected with the directional drill rod (1), the lower nonmagnetic drill rod (23) is connected with a screw drilling tool (3), one end of the probe outer tube (22) is connected with the upper nonmagnetic drill rod (21), the other end of the probe outer tube is connected with the lower nonmagnetic drill rod (23), the measuring probe tube (24) is positioned in the probe outer tube (22), the measuring probe tube (24) is connected with a cable (241), and the cable (241) extends out of the directional drill rod (1) along the upper nonmagnetic drill rod (21).
3. A screw motor coring structure according to claim 1, wherein: the angle range of the elbow of the screw drilling tool (3) is 0-1.5 degrees; the length of the core tube (4) ranges from 0.5m to 3.0m.
4. A screw motor coring structure according to claim 3, wherein: the larger the elbow angle of the screw drilling tool (3) is, the shorter the length of the core barrel (4) is; the longer the length of the core barrel (4), the smaller the elbow angle of the screw drilling tool (3).
5. A screw motor coring structure according to claim 1, wherein: the core barrel (4) is connected with the transmission shaft (31) through a reducing joint (41).
6. The technique for coring a directional drilling whipstock of a screw motor coring structure according to any one of claims 1 to 5, comprising the steps of:
Step 1: selecting a proper drilling tool assembly; after the directional drilling finishes drilling of the inclined hole section along the inclination angle of the opening and reaches the starting point of the deflecting section, lifting the drilling to the ground surface, and replacing a drilling tool assembly aiming at the deflecting section;
step 2: the method comprises the steps of sequentially connecting an upper nonmagnetic drill rod (21), a measuring probe tube (24) and a lower nonmagnetic drill rod (23) in a directional drill rod (1), sequentially installing a selected screw drilling tool (3), a core barrel (4) and a coring bit (5) at the front end of the drilling tool, and replacing the directional bit (6) at the front end of the screw drilling tool by the core barrel (4) and the coring bit (5) during conventional directional deflection;
Step 3: after the drilling tool assembly is installed, connecting a measuring system, resetting and correcting the tool face angle of the drilling tool at an orifice, and drilling down to the bottom of a hole;
step 4: before driller, connecting a measurement while drilling joint behind a drill rod, and measuring a drilling track;
Step 5: calculating the tool face angle of the secondary screw drilling tool (3) according to drilling design track data, turning the power head of the drilling machine clockwise, observing a graphic interface of a measurement while drilling system, and turning the drilling tool to the calculated tool face;
Step 6: removing a measurement while drilling joint behind a drill rod, connecting a water joint, starting a slurry pump, adjusting drilling parameters, performing sliding directional drilling with proper weight on bit and pump amount, enabling a drilling track to extend along the direction of the current tool surface, and simultaneously enabling a core bit (5) to crush a rock stratum at the front end to enable a core to enter a core barrel (4);
Step 7: after the core is fully filled with the core tube (4), the water joint is removed, the measurement while drilling system is connected again, the current measuring point is subjected to data measurement, the drilling track data is obtained, and the drilling track data is compared with the drilling design track data;
step 8: after the drilling track data comparison is completed, a drilling tool in the hole is lifted, a core barrel (4) at the front end of the screw drilling tool (3) is disassembled, a coring bit (5) is disassembled, a core in the core barrel (4) is taken out, and the directional deflecting and coring drilling of the present time are completed;
step 9: and (3) repeating the steps 2-8, gradually drilling until the directional drilling deflecting section is completely completed, and drilling into a horizontal hole section where the tunnel buries.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410098719.7A CN118008179A (en) | 2024-01-24 | 2024-01-24 | Screw motor coring structure and coring technology of directional drilling deflecting section thereof |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410098719.7A CN118008179A (en) | 2024-01-24 | 2024-01-24 | Screw motor coring structure and coring technology of directional drilling deflecting section thereof |
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| Publication Number | Publication Date |
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| CN118008179A true CN118008179A (en) | 2024-05-10 |
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| CN202410098719.7A Pending CN118008179A (en) | 2024-01-24 | 2024-01-24 | Screw motor coring structure and coring technology of directional drilling deflecting section thereof |
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- 2024-01-24 CN CN202410098719.7A patent/CN118008179A/en active Pending
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