CN213709503U - High-pressure rotary-cut drill bit - Google Patents
High-pressure rotary-cut drill bit Download PDFInfo
- Publication number
- CN213709503U CN213709503U CN202022390998.4U CN202022390998U CN213709503U CN 213709503 U CN213709503 U CN 213709503U CN 202022390998 U CN202022390998 U CN 202022390998U CN 213709503 U CN213709503 U CN 213709503U
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- China
- Prior art keywords
- drill bit
- cutting knife
- sleeve
- rotary
- nozzle
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- Expired - Fee Related
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- 238000005507 spraying Methods 0.000 claims abstract description 39
- 239000002002 slurry Substances 0.000 claims abstract description 20
- 238000009434 installation Methods 0.000 claims description 34
- 230000002093 peripheral effect Effects 0.000 claims description 10
- 230000000149 penetrating effect Effects 0.000 claims description 3
- 230000000694 effects Effects 0.000 abstract description 11
- 238000000034 method Methods 0.000 abstract description 10
- 239000011440 grout Substances 0.000 abstract 1
- 229920000915 polyvinyl chloride Polymers 0.000 description 27
- 239000004800 polyvinyl chloride Substances 0.000 description 27
- 239000002689 soil Substances 0.000 description 14
- 239000004568 cement Substances 0.000 description 9
- 238000005553 drilling Methods 0.000 description 8
- 238000006243 chemical reaction Methods 0.000 description 4
- 238000010276 construction Methods 0.000 description 4
- 238000003756 stirring Methods 0.000 description 4
- 239000007788 liquid Substances 0.000 description 3
- 229920003023 plastic Polymers 0.000 description 3
- 239000004033 plastic Substances 0.000 description 3
- 238000010586 diagram Methods 0.000 description 2
- 239000007921 spray Substances 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000005253 cladding Methods 0.000 description 1
- 238000007596 consolidation process Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 239000012634 fragment Substances 0.000 description 1
- 238000002347 injection Methods 0.000 description 1
- 239000007924 injection Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 238000003466 welding Methods 0.000 description 1
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- Earth Drilling (AREA)
Abstract
The application discloses a high-pressure rotary-cut drill bit, which comprises a rotary-jet drill bit body, wherein a blind hole for slurry to pass through is formed in the rotary-jet drill bit body; the nozzle is arranged on the rotary jet drill bit body, a channel for slurry to pass through is arranged on the nozzle, and the channel is communicated with the blind hole; the cutting knives are arranged on the rotary spraying drill bit body and are distributed opposite to the nozzle; and the cutting knife is positioned above the nozzle by taking the lifting direction of the rotary jet drill bit body as a reference. The application provides a high pressure rotary-cut drill bit, in the jet grouting process, can break the cutting PVC protects the wall pipe more fast, reduces the influence that PVC protects the wall pipe to grout spraying effect to guarantee to become the stake diameter.
Description
Technical Field
The application relates to the field of construction of jet grouting piles, in particular to a high-pressure rotary-cut drill bit.
Background
The jet grouting pile is characterized in that cement slurry is sprayed into a soil layer by a high-pressure rotating nozzle to be mixed with a soil body, so as to form a columnar consolidation body with a certain diameter; the jet grouting pile is suitable for treating foundations such as silt, mucky soil, flow plastic, soft plastic or plastic cohesive soil, silt, sandy soil, loess, plain filling soil, gravel soil and the like.
The construction process of the jet grouting pile comprises the following steps: measuring and positioning, positioning a drilling machine, drilling holes by the drilling machine, detecting final holes, positioning a high-spraying trolley, performing jet grouting and forming piles.
And after the pre-drilling is finished, removing the geological drilling rig, and carrying out in-place rotary spraying operation on the high-spraying trolley. A time difference exists between the working procedures of removing the geological drilling rig and the high-spraying trolley in-place operation, and in the time difference, the preformed hole may collapse, so that the spray head in the hole cannot be lowered, the hole can be drilled again, the phenomenon of forming the hole again for two times or three times often occurs, and the construction period is directly influenced.
In the prior art, a method for pre-protecting a hole collapse is provided, wherein a PVC wall protection pipe is placed after pre-forming of the hole, so that the hole collapse during the interval from hole forming to high-speed trolley grouting is prevented; in the subsequent rotary spraying grouting, the high-pressure cement slurry breaks through and cuts the PVC wall protection pipe, and then is stirred with the surrounding soil body to form a pile body, so that the smooth construction is ensured.
The high-pressure cement slurry impacts on the PVC wall protecting pipe, the PVC wall protecting pipe can block the high-pressure cement slurry firstly, and after the impact force of the high-pressure cement slurry on the PVC wall protecting pipe is greater than the bearing capacity of the wall of the PVC wall protecting pipe, the PVC wall protecting pipe is broken and is cut into small fragments by the high-pressure cement slurry.
In the process, the PVC retaining wall pipe obviously interferes the spraying effect of the high-pressure cement slurry, the stirring degree of the high-pressure cement slurry and the surrounding soil body is reduced, and the pile forming diameter of the jet grouting pile is influenced.
SUMMERY OF THE UTILITY MODEL
In order to realize faster breaking and cutting of the PVC wall protection pipe and reduce the influence of the PVC wall protection pipe on the cement paste spraying effect in the rotary spraying grouting process so as to ensure the diameter of a formed pile, the application provides a high-pressure rotary cutting drill bit.
The application provides a high pressure rotary-cut drill bit adopts following technical scheme:
a high-pressure rotary cutting drill bit comprises a rotary spraying drill bit body, wherein a blind hole for slurry to pass through is formed in the rotary spraying drill bit body; the nozzle is arranged on the rotary jet drill bit body, a channel for slurry to pass through is arranged on the nozzle, and the channel is communicated with the blind hole; and the cutting knife is arranged on the rotary spraying drill bit body, the lifting direction of the rotary spraying drill bit body is used as a reference, and the cutting knife is positioned above the nozzle.
Through adopting above-mentioned technical scheme, high-pressure rotary-cut drill bit limit spouts the limit upwards to promote soon, and the cutting knife contacts PVC wall protection pipe earlier than the nozzle, cuts PVC wall protection pipe for the nozzle can not have the PVC wall protection pipe of monolithic to form the obstruction to high-pressure thick liquid in subsequent route of advancing, thereby guarantees the injection effect of high-pressure thick liquid to peripheral soil body, improves the stirring degree of high-pressure thick liquid and peripheral soil body, and then guarantees the stake diameter of forming of spout soon.
The application is further configured to: the cutting knife and the nozzle are distributed oppositely.
Through adopting above-mentioned technical scheme, the produced reaction force of the rotary spraying drill bit body that carries out the high pressure rotary spraying operation is very powerful, provides the power of the quick cutting PVC wall protection pipe for the cutting knife that is located the nozzle back.
The application is further configured to: the cutting knife is welded on the peripheral surface of the rotary jet drill bit body.
Through adopting above-mentioned technical scheme, the cutting knife directly adopts welding mode to fix on the jet-grouting drill bit body outer peripheral face, and fixed mode is the most common use and durable on the workplace, makes things convenient for workman field operation.
The application is further configured to: the rotary spraying drill bit is characterized in that an installation block is welded on the outer peripheral surface of the rotary spraying drill bit body, and the cutting knife is detachably fixed on the installation block.
Through adopting above-mentioned technical scheme, the cutting knife can be dismantled and fix on the installation piece, makes things convenient for the later stage cutting knife to change after wearing and tearing are serious to guarantee the cutting effect of cutting knife.
The application is further configured to: the end part of the cutting knife, which is far away from the tool bit, is fixedly connected with a mounting plate, a sleeve is sleeved outside the cutting knife, one end of the sleeve is provided with a closing structure, and the other end of the sleeve is provided with internal threads; the sleeve is in threaded connection with the mounting block, and the mounting plate is pressed on the mounting block through the closing-up structure.
By adopting the technical scheme, when the cutting knife is installed, the installation plate is pressed against one side of the installation block, which is far away from the rotary spraying drill bit body, the sleeve is sleeved on the cutting knife and is in threaded connection with the installation block, and finally the installation plate is pressed on the installation block through the closing-up structure, so that the fixed installation of the cutting knife on the installation block is realized; when the sleeve is disassembled, the sleeve is reversed. The dismouting process is swift convenient, makes the operation of later stage change cutting knife more quick smooth.
The application is further configured to: the end part of the cutting knife, which is far away from the tool bit, is fixedly connected with a dovetail-shaped fixed block, the end part of the mounting block is provided with a fixed groove, and the fixed block is embedded in the fixed groove; the mounting block is connected with a sleeve in a threaded manner, the sleeve is sleeved on the cutting knife, and the inner wall of the sleeve is abutted to the outer wall of the cutting knife.
By adopting the technical scheme, the fixing block is embedded in the fixing groove, namely, the cutting knife is pre-fixed on the mounting block; then establish the sleeve pipe cover on the cutting knife, the intraductal wall of cover is inconsistent with cutting knife outer wall, and the sleeve pipe is with the partial cladding of cutting knife blade simultaneously, treats sleeve pipe and installation piece threaded connection back, and the sleeve pipe supports the cutting knife blade to improve the whole rigidity of cutting knife, guarantee the cutting effect of cutting knife.
The application is further configured to: all be provided with the latch on the inconsistent plane of installation piece and mounting panel, the latch looks joint of installation piece and mounting panel.
Through adopting above-mentioned technical scheme, back together, the mutual interlock joint of tooth between them is installed with installation piece butt to restriction cutting knife and the relative motion between the installation piece, make more stable the installing on the installation piece of cutting knife.
The application is further configured to: the mounting block and the sleeve are both provided with pin holes in a radial penetrating manner, and split pins penetrate through the pin holes.
Through adopting above-mentioned technical scheme, insert in the pinhole and establish the split pin, utilize the split pin restriction sleeve pipe to rotate to prevent that sleeve pipe and installation piece screw from becoming flexible, guarantee the stability of cutting knife installation.
The application is further configured to: the cutting knife is positioned 5-10cm above the nozzle.
By adopting the technical scheme, the cutting knife is positioned above the nozzle by 5-10cm, and the reaction force of the nozzle can be utilized to the maximum extent so as to realize the rapid cutting of the PVC wall protection pipe by the cutting knife.
In summary, the present application includes at least one of the following beneficial technical effects:
1. the cutter cuts the PVC wall protection pipe before the nozzle, and simultaneously, the reaction force generated by high-pressure rotary spraying provides power for quick cutting for the cutter, so that the nozzle cannot block the high-pressure slurry by the whole PVC wall protection pipe in the subsequent advancing route, the stirring degree of the high-pressure slurry and the surrounding soil body is improved, and the pile forming diameter of the rotary spraying pile is ensured;
2. the cutting knife can be dismantled and fix on spouting the drill bit body soon, makes things convenient for the later stage cutting knife to wear and tear and changes after serious to guarantee the cutting effect of cutting knife.
Drawings
FIG. 1 is a schematic structural diagram of embodiment 1 of the present application;
FIG. 2 is a schematic structural view of a detaching structure of a cutting knife in embodiment 2 of the present application;
fig. 3 is a schematic structural diagram of a detaching structure of a cutting knife in embodiment 3 of the present application.
Description of reference numerals: 1. a jet grouting drill body; 2. a nozzle; 3. a cutting knife; 31. mounting a plate; 32. a fixed block; 4. mounting blocks; 41. fixing grooves; 5. a sleeve; 51. a closing structure; 6. teeth; 7. and a cotter pin.
Detailed Description
The present application is described in further detail below with reference to the attached drawings.
The embodiment of the application discloses a high-pressure rotary-cut drill bit, which is suitable for a high-pressure rotary-spraying process with a PVC (polyvinyl chloride) wall protection pipe arranged below a lead hole.
Example 1
Referring to fig. 1, the high-pressure rotary cutting drill comprises a rotary spraying drill body 1 and a nozzle 2 arranged on the rotary spraying drill body 1, wherein the rotary spraying drill body 1 is provided with a blind hole, the nozzle 2 is provided with a channel, and the channel is communicated with the blind hole; high-pressure slurry enters the rotary jet drill bit body 1 through the blind hole and is jetted from the channel of the nozzle 2.
The outer wall of the rotary spraying drill bit body 1 is horizontally welded with a cutting knife 3, the cutting knife 3 is arranged opposite to the nozzle 2, the lifting direction of the rotary spraying drill bit body 1 is used as a reference, and the cutting knife 3 is located 5-10cm above the nozzle 2. The length of the cutting knife 3 is related to the diameter of the PVC wall protecting pipe, so that the cutter head of the cutting knife 3 is abutted against the inner wall of the PVC wall protecting pipe or the interval of 1-2cm is reserved between the cutter head and the inner wall of the PVC wall protecting pipe.
In the high-pressure rotary spraying process, after hole guiding of a drilling machine is completed, a PVC wall protection pipe is placed in the hole, the drilling machine is removed, a high-pressure rotary cutting drill bit is placed to the bottom of the hole by a high-pressure rotary cutting trolley provided with the high-pressure rotary cutting drill bit, and then rotary spraying operation is carried out.
Because the high-pressure rotary-cut drill bit is lifted upwards while rotating to spray, the cutting knife 3 contacts the PVC retaining wall pipe before the nozzle 2 to cut the PVC retaining wall pipe; and the reaction force generated by the rotary spraying drill bit body 1 for carrying out the high-pressure rotary spraying operation is very strong, and provides power for rapidly cutting the PVC wall protection pipe for the cutting knife 3 positioned at the back of the nozzle 2, so that the nozzle 2 cannot form a block on the high-pressure slurry by the whole PVC wall protection pipe in the subsequent advancing route, the spraying effect of the high-pressure slurry on the peripheral soil body is ensured, the stirring degree of the high-pressure slurry and the peripheral soil body is improved, and the pile forming diameter of the rotary spraying pile is ensured.
3 cutter heads of cutting knife are worn to a certain degree, utilize the instrument to remove cutting knife 3, weld cutting knife 3 again to guarantee the cutting effect of cutting knife 3.
Example 2
Referring to fig. 2, the present embodiment is different from embodiment 1 in that the cutting blade 3 is detachably and fixedly mounted on the rotary jet drill bit body 1.
The cutting knife 3 and the jet-grouting drill bit body 1 are provided with detachable structures, each detachable structure comprises an installation block 4 and a sleeve 5, and the installation blocks 4 are welded on the outer peripheral surface of the jet-grouting drill bit body 1 and distributed relative to the nozzle 2. Sleeve 5 one end is equipped with binding off structure 51, and the internal thread has been arranged to the other end, has arranged the external screw thread on the installation piece 4 outer wall, makes sleeve 5 threaded connection on installation piece 4.
The tip rigid coupling that cutting knife 3 deviates from the tool bit has mounting panel 31, and mounting panel 31 size is greater than 3 section size of cutting knife.
When the cutting knife 3 is installed, the mounting plate 31 is pressed against one side, away from the rotary spraying drill bit body 1, of the mounting block 4, the sleeve 5 is sleeved on the cutting knife 3 and is in threaded connection with the mounting block 4, and finally the mounting plate 31 is pressed on the mounting block 4 through the closing-up structure 51, so that the fixed installation of the cutting knife 3 on the mounting block 4 is realized; when the sleeve is disassembled, the sleeve 5 is reversed. The dismouting process is swift convenient, makes the operation of later stage change cutting knife 3 more smooth fast.
In order to improve the stability of cutting knife 3 installation on installation piece 4, all be provided with bar tooth 6 in one side of installing panel 31 and installation piece 4 mutual conflict, after installing panel 31 and installation piece 4 butt are in the same place, tooth 6 interlock joint each other between them to the relative motion between restriction cutting knife 3 and the installation piece 4 makes more stable the installing on installation piece 4 of cutting knife 3.
Furthermore, pin holes are formed in the mounting block 4 and the sleeve 5 in a penetrating mode along the radial direction, the sleeve 5 presses the mounting plate 31 on the mounting block 4, the pin holes correspond to each other, then the split pin 7 is inserted into the pin holes, and the sleeve 5 is limited to rotate by the split pin 7, so that the sleeve 5 and the mounting block 4 are prevented from loosening in threads, and the mounting stability of the cutting knife 3 is guaranteed.
Example 3
Referring to fig. 3, the present embodiment is different from embodiment 2 in that the connection manner of the cutting blade 3 and the mounting block 4 is configured to be inserted; the sleeve 5 is a standard straight pipe, and the inner diameter of the sleeve 5 is matched with the outer diameter of the cutting knife 3.
Specifically, a dovetail-shaped fixing block 32 is fixedly connected to the end part of the cutting knife 3, which is far away from the tool bit, a fixing groove 41 which is matched with the end part of the mounting block 4, which is far away from the rotary jet drill bit body 1, is formed in one side of the mounting block 4, and the fixing block 32 is embedded in the fixing groove 41, so that the cutting knife 3 is pre-fixed on the mounting block 4; then establish sleeve pipe 5 cover on cutting knife 3, 5 inner walls of sleeve pipe and 3 outer walls of cutting knife are inconsistent, and sleeve pipe 5 partially wraps the blade of cutting knife 3 simultaneously, treats sleeve pipe 5 and 4 threaded connection backs of installation piece, and sleeve pipe 5 supports the blade of cutting knife 3 to improve the whole rigidity of cutting knife 3, guarantee the cutting effect of cutting knife 3. The sleeve 5 is retained by a cotter pin 7 as in the mounting block 4.
The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.
Claims (9)
1. A high-pressure rotary cutting drill bit is characterized in that: comprises that
The rotary spraying drill bit comprises a rotary spraying drill bit body (1), wherein a blind hole for slurry to pass through is formed in the rotary spraying drill bit body (1);
the nozzle (2) is mounted on the rotary jet drill bit body (1), a channel for slurry to pass through is formed in the nozzle (2), and the channel is communicated with the blind hole;
install cutting knife (3) on spouting drill bit body (1) soon to spout drill bit body (1) lifting direction soon as the benchmark, cutting knife (3) are located nozzle (2) top.
2. The high-pressure rotary cut drill bit of claim 1, wherein: the cutting knife (3) and the nozzle (2) are distributed oppositely.
3. The high-pressure rotary cut drill bit of claim 1, wherein: the cutting knife (3) is welded on the peripheral surface of the rotary jet drill bit body (1).
4. The high-pressure rotary cut drill bit of claim 1, wherein: the rotary spraying drill bit is characterized in that an installation block (4) is welded on the outer peripheral surface of the rotary spraying drill bit body (1), and the cutting knife (3) is detachably fixed on the installation block (4).
5. The high pressure rotary cut drill bit of claim 4, wherein: the end part, away from the tool bit, of the cutting knife (3) is fixedly connected with a mounting plate (31), a sleeve (5) is sleeved outside the cutting knife (3), one end of the sleeve (5) is provided with a closing structure (51), and internal threads are distributed at the other end of the sleeve; the sleeve (5) is in threaded connection with the mounting block (4), and the mounting plate (31) is pressed on the mounting block (4) through the closing-up structure (51).
6. The high pressure rotary cut drill bit of claim 4, wherein: the end part, away from the tool bit, of the cutting knife (3) is fixedly connected with a dovetail-shaped fixing block (32), the end part of the mounting block (4) is provided with a fixing groove (41), and the fixing block (32) is embedded in the fixing groove (41); the mounting block (4) is connected with a sleeve (5) in a threaded manner, the sleeve (5) is sleeved on the cutting knife (3), and the inner wall of the sleeve (5) is abutted to the outer wall of the cutting knife (3).
7. The high pressure rotary cut drill bit of claim 5, wherein: all be provided with the latch on the inconsistent plane of installation piece (4) and mounting panel (31), the latch looks joint of installation piece (4) and mounting panel (31).
8. The high pressure rotary cut drill bit of claim 5 or 6, wherein: the mounting block (4) and the sleeve (5) are provided with pin holes in a radial penetrating manner, and split pins (7) are inserted into the pin holes.
9. The high-pressure rotary cut drill bit according to claim 1 or 2, wherein: the cutting knife (3) is positioned 5-10cm above the nozzle (2).
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022390998.4U CN213709503U (en) | 2020-10-23 | 2020-10-23 | High-pressure rotary-cut drill bit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202022390998.4U CN213709503U (en) | 2020-10-23 | 2020-10-23 | High-pressure rotary-cut drill bit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN213709503U true CN213709503U (en) | 2021-07-16 |
Family
ID=76800508
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202022390998.4U Expired - Fee Related CN213709503U (en) | 2020-10-23 | 2020-10-23 | High-pressure rotary-cut drill bit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN213709503U (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114086547A (en) * | 2021-12-19 | 2022-02-25 | 江苏省无锡探矿机械总厂有限公司 | Rotary mechanism of high pressure jet grouting |
-
2020
- 2020-10-23 CN CN202022390998.4U patent/CN213709503U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114086547A (en) * | 2021-12-19 | 2022-02-25 | 江苏省无锡探矿机械总厂有限公司 | Rotary mechanism of high pressure jet grouting |
| CN114086547B (en) * | 2021-12-19 | 2024-05-03 | 江苏省无锡探矿机械总厂有限公司 | High-pressure rotary spraying rotating mechanism |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20210716 |