CN111734318B - Multifunctional hydraulic safety device for oil pipe - Google Patents
Multifunctional hydraulic safety device for oil pipe Download PDFInfo
- Publication number
- CN111734318B CN111734318B CN202010612200.8A CN202010612200A CN111734318B CN 111734318 B CN111734318 B CN 111734318B CN 202010612200 A CN202010612200 A CN 202010612200A CN 111734318 B CN111734318 B CN 111734318B
- Authority
- CN
- China
- Prior art keywords
- pipe section
- pressure
- piston
- inner cylinder
- pressure equalizing
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 239000011148 porous material Substances 0.000 claims description 16
- 238000007789 sealing Methods 0.000 claims description 6
- 230000007246 mechanism Effects 0.000 abstract description 7
- 230000007547 defect Effects 0.000 abstract description 3
- 239000003208 petroleum Substances 0.000 abstract description 2
- 238000005553 drilling Methods 0.000 description 7
- 239000012530 fluid Substances 0.000 description 7
- 239000003129 oil well Substances 0.000 description 4
- 238000010276 construction Methods 0.000 description 2
- 230000000903 blocking effect Effects 0.000 description 1
- 230000005465 channeling Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 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
- E21B17/00—Drilling rods or pipes; Flexible drill strings; Kellies; Drill collars; Sucker rods; Cables; Casings; Tubings
- E21B17/02—Couplings; joints
- E21B17/08—Casing joints
-
- 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
- E21B34/00—Valve arrangements for boreholes or wells
- E21B34/06—Valve arrangements for boreholes or wells in wells
- E21B34/08—Valve arrangements for boreholes or wells in wells responsive to flow or pressure of the fluid obtained
Landscapes
- 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)
- Safety Valves (AREA)
- Actuator (AREA)
Abstract
The invention relates to a multifunctional hydraulic safety device for an oil pipe, which belongs to the technical field of petroleum operation equipment and comprises a discarded pipe section, a pressure equalizing pipe section and a pressure relief pipe section, wherein the discarded pipe section is formed by internally and externally inserting an upper pipe section and a lower pipe section; a pressure equalizing inner cylinder is arranged in the pressure equalizing pipe section; the pressure relief pipe section is connected with the upper end of the pressure equalizing pipe section, and a sliding sleeve is in clearance fit in the pressure relief pipe section. According to the multifunctional hydraulic safety device for the oil pipe, a pressurizing link is omitted, manual energy can be removed through a mechanical mechanism, a hydraulic valve cover structure is adopted by using a pressure difference principle, a safety valve mechanism is adopted, a bypass valve is automatically opened under overpressure, and the safety valve is automatically closed under misoperation, so that the structural design is reasonable, the defects of the prior art are effectively overcome, and the requirements of actual conditions are met.
Description
Technical Field
The invention belongs to the technical field of petroleum operation equipment, and particularly relates to a multifunctional hydraulic safety device for an oil pipe.
Background
The hydraulic safety joint is widely applied to the layered exploitation of oil wells in casing pipes and the gas and water blocking, the implementation of the technology can shorten the well repairing operation time of the oil wells, recover the production of some production-stopped oil wells caused by serious gas channeling and the like, and realize the layered exploitation and selective exploitation of the oil wells completed by small-diameter casing pipes, the hydraulic safety joint is a downhole tool for throwing the embedded clamping part of a well completion pipe column into a well, when the well completion pipe column cannot be taken out, the upper pipe column and the lower pipe column are separated by a release device, so that the upper pipe column is taken out, but the prior art has a design similar to the tool, the implementation of the releasing function requires throwing and pressing, and the prior related tools adopt a one-way valve mechanism which is of a torsion spring and a valve cover in order to prevent the sudden pressure rise of high-pressure gas at the ground and the sudden pressure of the high-pressure oil which is higher than the reverse upward flow of drilling fluid to generate danger, the safety performance is poor, some mechanisms with bypass valves are used, when drilling fluid circulates, a drill bit at the lower part is blocked, overpressure in the pipe is generated, the pump is stopped and a ball is thrown, the pump is started to press a shearing pin, the bypass is opened, the operation is complex, and the time is long.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provides a multifunctional hydraulic safety device for an oil pipe.
The invention relates to a multifunctional hydraulic safety device for an oil pipe, which consists of a discarded pipe section, a pressure equalizing pipe section and a pressure relief pipe section, wherein the discarded pipe section consists of an upper pipe section and a lower pipe section which are inserted inside and outside; a pressure equalizing inner cylinder is arranged in the pressure equalizing pipe section, a piston is embedded in an annular gap between the pressure equalizing inner cylinder and the pressure equalizing pipe section, a piston valve cover is radially arranged in the piston, a sliding groove of the piston valve cover is arranged in the middle section of the pressure equalizing inner cylinder, an upper pressure guide hole for communicating the inner cylinder with an upper piston cylinder is arranged on the pipe wall at the upper end of the pressure equalizing inner cylinder, a lower pressure guide hole for communicating the inner cylinder with a lower piston cylinder is arranged on the pipe wall at the lower end of the pressure equalizing inner cylinder, and a pressure equalizing valve for conducting the high pressure at the upper part of the pressure equalizing inner cylinder and the low pressure at the lower part of the pressure equalizing inner cylinder in a one-way manner is arranged on the periphery of the piston valve cover; the pressure relief pipe section is connected with the lower end of the pressure equalizing pipe section, a sliding sleeve is in clearance fit in the pressure relief pipe section, a return spring is arranged on a lower end seat of the sliding sleeve, an upper end seat of the sliding sleeve is arranged on the pressure lifting piston, a constant pressure relief pore valve communicated with a high pressure cavity of the oil pipe is arranged in a piston cylinder on the upper edge of the lifting piston, and a pressure relief pore is radially arranged on the pipe wall of the pressure relief pipe section corresponding to the upper part of the sliding sleeve.
As a further improvement of the invention, the upper end of the pull rod is obliquely pulled and inserted into the lap joint pin of the upper pipe section and the lower pipe section.
As a further improvement of the invention, the balls are arranged in the ball grooves of the sliding sleeve, and the number of the balls arranged in the ball grooves of the sliding sleeve is more than one.
As a further improvement of the invention, the pressure equalizing pipe section and the pressure relief pipe section are connected through threads.
As a further improvement of the invention, a sealing lock nut is fixed on the outer side of the pore passage of the constant pressure relief pore passage valve, a safety valve piston rod is arranged on the inner side of the pore passage, a safety valve piston seal is arranged in a groove of the safety valve piston rod, one end of a safety valve spring is sleeved on the safety valve piston rod, and the other end of the safety valve spring is abutted against the sealing lock nut.
As a further improvement of the invention, the upper end of the sliding sleeve is connected with the locking hook through a joint pin.
According to the multifunctional hydraulic safety device for the oil pipe, a pressing link is omitted, a mechanical mechanism can achieve a releasing function, a hydraulic valve cover structure is adopted by using a pressure difference principle, and meanwhile, a safety valve mechanism is adopted, and a bypass valve is automatically opened by overpressure, so that the multifunctional hydraulic safety device for the oil pipe is reasonable in structural design, effectively overcomes the defects of the prior art, and meets the requirements of actual conditions.
Drawings
FIG. 1 is a schematic structural view of a multifunctional hydraulic safety device for an oil pipe according to the present invention;
FIG. 2 is a schematic view of the construction of a discarded pipe section of the present invention;
FIG. 3 is a schematic view of the construction of a pressure equalizing pipe section according to the present invention;
FIG. 4 is a schematic view of the pressure relief segment of the present invention.
Detailed Description
The invention relates to a multifunctional hydraulic safety device for an oil pipe, which consists of a discarded pipe section 1, a pressure equalizing pipe section 2 and a pressure relief pipe section 3, wherein the discarded pipe section 1 consists of an upper pipe section 25 and a lower pipe section 26 which are inserted inside and outside, the upper opening of the upper pipe section 25 is connected with the lower part of the previous oil pipe, a hydraulic impact hammer 4 in clearance fit is arranged at the axis of the upper inner cavity of the upper pipe section 25, an inner cylinder 5 is arranged at the axis of the lower part of the lower pipe section 26, a sliding sleeve 6 is in clearance fit in the annular clearance between the inner cylinder 5 and the lower pipe section 26, a thrust spring 8 is embedded between the lower end of the sliding sleeve 6 and a limiting seat 7, the upper end of the sliding sleeve 6 is connected with a lock hook 9, the lock hook 9 is buckled by a lock catch 10, a pull rod 11 is hinged to the upper edge of the inner cylinder 5, and the upper end of the pull rod 11 is pulled and inserted into a pin 12 at the overlapping opening of the upper pipe section 25 and the lower pipe section 26; a pressure equalizing inner cylinder 13 is arranged in the pressure equalizing pipe section 2, a piston 14 is embedded in an annular gap between the pressure equalizing inner cylinder 13 and the pressure equalizing pipe section 2, a piston valve cover 15 is radially arranged in the piston 14, a sliding groove 16 of the piston valve cover 15 is arranged in the middle section of the pressure equalizing inner cylinder 13, an upper pressure guide hole 17 for communicating the inner cylinder 5 with an upper cylinder of the piston 14 is arranged on the pipe wall at the upper end of the pressure equalizing inner cylinder 13, a lower pressure guide hole 18 for communicating the inner cylinder 5 with a lower cylinder of the piston 14 is arranged on the pipe wall at the lower end of the pressure equalizing inner cylinder 13, and a pressure equalizing valve 19 for conducting the upper high pressure and the lower low pressure of the pressure equalizing inner cylinder 13 in a one-way is arranged around the piston valve cover 15; the pressure relief pipe section 3 is connected with the lower end of the pressure equalizing pipe section 2, a sliding sleeve 20 is in clearance fit in the pressure relief pipe section 3, the lower end of the sliding sleeve 20 is seated with a return spring 21, the upper end of the sliding sleeve is seated on a pressure lifting piston 22, a constant pressure relief pore valve 23 communicated with a high pressure cavity of an oil pipe is arranged in a piston cylinder at the upper edge of the lifting piston 22, and a pressure relief pore 24 is radially arranged on the pipe wall of the pressure relief pipe section 3 corresponding to the upper part of the sliding sleeve 20.
When the abandoned pipe section 1 is separated from the lower oil pipe, the sliding sleeve 6 is provided with a part which extrudes the pull rod 11 to separate the upper pipe section 25 from the lower pipe section 26, the sliding sleeve 6 provides elastic force under the action of pre-tightening and compressing the thrust spring 8 through the limiting seat 7, the upper end of the sliding sleeve 6 is connected with the latch hook 9 through the knuckle pin 32, the latch hook 9 serving as a locking mechanism blocks the sliding sleeve 6 from being locked to the upper edge of the inner cylinder 5, the upper edge of the inner cylinder 5 is hinged with the pull rod 11, the upper end of the pull rod 11 obliquely pulls the pin 12 inserted into the overlapping opening of the upper pipe section 25 and the lower pipe section 26, the pin 12 has the function of connecting the upper pipe section 25 with the lower pipe section 26, the latch hook 9 is locked by the latch 10 of an opening piece which can be communicated with drilling fluid and is arranged at the upper end of the inner cylinder 5, when the impact hammer 4 with unlocking action is thrown through the upper opening of the upper pipe section 25, the front end lance tip of the impact hammer 4 touches the latch 10 to separate the latch hook 10 from the latch hook 9, since one or more balls 27 are installed in the ball grooves of the slide sleeve 6, the slide sleeve 6 moves forward by the elastic force of the thrust spring 8 which acts to compress the elastic force of the slide sleeve 6, and presses the pull rod 11, so that the pull rod 11 retracts and the hooking pin 12 moves inward, and the upper pipe section 25 is separated from the lower pipe section 26.
When the internal pressure enters the piston cavity of the piston valve cover 15 with the execution function of the differential pressure check valve device through the lower pressure guide holes 17 and the pressure guide holes 18 on the two sides of the pressure equalizing inner cylinder 13, when the pressure before the valve is greater than the pressure after the valve, the pressure equalizing valve 19 is opened, the drilling fluid enters the piston cavity through the lower pressure guide holes 17 to push the piston 14 to move backwards, when the pressure after the valve is greater than the pressure before the valve, the pressure equalizing valve 19 is closed, the drilling fluid enters the piston cavity through the pressure guide holes 18 to push the piston 14 to move forwards, so that the differential pressure check function is achieved, and the lower pressure guide holes 17 and the pressure guide holes 18 are pressure inlets before the valve and after the valve and are connected with the inner side of the piston in a sliding mode.
A sealing lock nut 28 is fixed on the outer side of the pore channel of the constant pressure relief pore channel valve 23, a safety valve piston rod 30 is arranged on the inner side of the pore channel, one end of a safety valve spring 29 is sleeved on the safety valve piston rod 30, and the other end of the safety valve spring abuts against the sealing lock nut 28; when the lower nozzle is blocked, the internal pressure is increased rapidly, the pressure pushes the safety valve piston rod 30 to move upwards, because the safety valve piston seal 31 is arranged in the groove of the safety valve piston rod 30, the safety valve piston rod 30 moves upwards after being pressurized to control the action of the actuator piston, the safety valve spring 29 is compressed, the safety valve spring 29 has the function of controlling the opening force through the elasticity, when the safety valve piston rod 30 moves to the inlet of the pressure lifting piston 22 which has the function of pushing the valve sleeve to the pressure relief pore channel 24, the pressure lifting piston 22 is pushed by the drilling fluid to push the sliding sleeve 20 which has the function of opening the pressure relief pore channel 24 to overcome the elasticity of the homing spring 21, the sliding sleeve moves to the pressure relief pore channel 24, and the overpressure drilling fluid circulates to the upper part of the drill rod through the pressure relief pore channel 24.
Claims (6)
1. A multifunctional hydraulic safety device for an oil pipe comprises a discarded pipe section (1), a pressure equalizing pipe section (2) and a pressure relief pipe section (3), and is characterized in that the discarded pipe section (1) is formed by inserting an upper pipe section (25) and a lower pipe section (26) inside and outside, the upper opening of the upper pipe section (25) is connected with the lower part of a previous oil pipe, a hydraulic impact hammer (4) in clearance fit is arranged at the axis of an upper inner cavity of the upper pipe section (25), an inner cylinder (5) is arranged at the axis of the lower part of the lower pipe section (26), a sliding sleeve (6) is in clearance fit with an annular gap between the inner cylinder (5) and the lower pipe section (26), a thrust spring (8) is embedded between the lower end of the sliding sleeve (6) and a limiting seat (7), a lock hook (9) is connected at the upper end of the sliding sleeve (6), a lock hook (10) is used for locking the opposite lock hook (9), and a pull rod (11) is hinged to the upper edge of the inner cylinder (5), the upper end of the pull rod (11) is pulled and inserted into a pin (12) at the overlapping opening of the upper pipe section (25) and the lower pipe section (26); a pressure equalizing inner cylinder (13) is arranged in the pressure equalizing pipe section (2), a piston (14) is embedded in an annular gap between the pressure equalizing inner cylinder (13) and the pressure equalizing pipe section (2), a piston valve cover (15) is radially arranged in the piston (14), a sliding groove (16) of the piston valve cover (15) is arranged in the middle section of the pressure equalizing inner cylinder (13), an upper pressure guide hole (17) for communicating the inner cylinder (5) with an upper cylinder of the piston (14) is formed in the pipe wall at the upper end of the pressure equalizing inner cylinder (13), a lower pressure guide hole (18) for communicating the inner cylinder (5) with a lower cylinder of the piston (14) is formed in the pipe wall at the lower end of the pressure equalizing inner cylinder (13), and a pressure equalizing valve (19) for conducting the upper high pressure and the lower low pressure of the pressure equalizing inner cylinder (13) in a one-way is arranged on the periphery of the piston valve cover (15); the pressure relief pipe section (3) is connected with the lower end of the pressure equalizing pipe section (2), a sliding sleeve (20) is in clearance fit in the pressure relief pipe section (3), a return spring (21) is arranged on a lower end seat of the sliding sleeve (20), the upper end seat of the sliding sleeve is arranged on a pressure lifting piston (22), a constant pressure relief pore valve (23) communicated with a high pressure cavity of an oil pipe is arranged in a piston cylinder on the upper edge of the lifting piston (22), and a pressure relief pore (24) is radially arranged on the pipe wall of the pressure relief pipe section (3) corresponding to the upper part of the sliding sleeve (20).
2. The multifunctional hydraulic safety device for oil pipe as claimed in claim 1, wherein the upper end of the pull rod (11) is inserted into the lap joint pin (12) of the upper pipe section (25) and the lower pipe section (26) in an inclined pulling manner.
3. The multifunctional hydraulic safety device for oil pipes according to claim 1, wherein the sliding sleeve (6) has balls (27) in the ball grooves, and the sliding sleeve (6) has more than one balls in the ball grooves.
4. The multifunctional hydraulic safety device for oil pipes as claimed in claim 1, wherein the pressure equalizing pipe section (2) is connected with the pressure relief pipe section (3) by screw threads.
5. The multifunctional hydraulic safety device for oil pipes according to claim 1, characterized in that a sealing lock nut (28) is fixed on the outer side of the orifice of the constant pressure relief orifice valve (23), a safety valve piston rod (30) is arranged on the inner side, a safety valve piston seal (31) is arranged in the groove of the safety valve piston rod (30), one end of a safety valve spring (29) is sleeved on the safety valve piston rod (30), and the other end of the safety valve spring abuts against the sealing lock nut (28).
6. The multifunctional hydraulic safety device for oil pipe as claimed in claim 1, wherein the upper end of the sliding sleeve (6) is connected with the latch hook (9) through a joint pin (32).
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202010612200.8A CN111734318B (en) | 2020-06-30 | 2020-06-30 | Multifunctional hydraulic safety device for oil pipe |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
CN202010612200.8A CN111734318B (en) | 2020-06-30 | 2020-06-30 | Multifunctional hydraulic safety device for oil pipe |
Publications (2)
Publication Number | Publication Date |
---|---|
CN111734318A CN111734318A (en) | 2020-10-02 |
CN111734318B true CN111734318B (en) | 2022-01-18 |
Family
ID=72653690
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN202010612200.8A Active CN111734318B (en) | 2020-06-30 | 2020-06-30 | Multifunctional hydraulic safety device for oil pipe |
Country Status (1)
Country | Link |
---|---|
CN (1) | CN111734318B (en) |
Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN201110163Y (en) * | 2007-07-18 | 2008-09-03 | 唐永强 | Ir-kill-job environment protection operation fluid pressure control uncoupling machine for water injection well |
CN102337864A (en) * | 2011-09-09 | 2012-02-01 | 中国海洋石油总公司 | Safety valve in pipe |
CN202152662U (en) * | 2011-07-15 | 2012-02-29 | 中国石油天然气股份有限公司 | Water hammer resistant liquid inlet device of expansion packer |
CN107461174A (en) * | 2017-09-26 | 2017-12-12 | 西南石油大学 | A kind of storm valve |
CN107476781A (en) * | 2016-06-07 | 2017-12-15 | 中国石油大学(华东) | All-hydraulic control storm valve |
CN209568995U (en) * | 2018-11-22 | 2019-11-01 | 中海油能源发展股份有限公司 | A kind of hydraulic selector tool for closedown sliding sleeve |
CN111206904A (en) * | 2019-11-15 | 2020-05-29 | 王凯 | Hydraulic switch capable of automatically realizing reversing balance of oil sleeve pressure |
-
2020
- 2020-06-30 CN CN202010612200.8A patent/CN111734318B/en active Active
Patent Citations (7)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN201110163Y (en) * | 2007-07-18 | 2008-09-03 | 唐永强 | Ir-kill-job environment protection operation fluid pressure control uncoupling machine for water injection well |
CN202152662U (en) * | 2011-07-15 | 2012-02-29 | 中国石油天然气股份有限公司 | Water hammer resistant liquid inlet device of expansion packer |
CN102337864A (en) * | 2011-09-09 | 2012-02-01 | 中国海洋石油总公司 | Safety valve in pipe |
CN107476781A (en) * | 2016-06-07 | 2017-12-15 | 中国石油大学(华东) | All-hydraulic control storm valve |
CN107461174A (en) * | 2017-09-26 | 2017-12-12 | 西南石油大学 | A kind of storm valve |
CN209568995U (en) * | 2018-11-22 | 2019-11-01 | 中海油能源发展股份有限公司 | A kind of hydraulic selector tool for closedown sliding sleeve |
CN111206904A (en) * | 2019-11-15 | 2020-05-29 | 王凯 | Hydraulic switch capable of automatically realizing reversing balance of oil sleeve pressure |
Also Published As
Publication number | Publication date |
---|---|
CN111734318A (en) | 2020-10-02 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
US10941625B2 (en) | Setting tools and assemblies for setting a downhole isolation device such as a frac plug | |
US10309180B2 (en) | Translocating wedge design for pressure-retaining seal | |
CN113202416B (en) | Multi-channel double-piston mechanical-hydraulic composite hole-making drilling tool and hole-making method | |
CN110173234B (en) | Self-expanding automatic oil drainage device | |
CN108915660B (en) | Fracturing method of coiled tubing with internal blowout prevention function | |
CN104989310B (en) | Horizontal well jarring stuck releasing device and construction method thereof | |
CN201074502Y (en) | Dual-valve plate type subsurface safety valve | |
CN116335579B (en) | Oil field well casing packer and non-cementing injection self-plugging staged fracturing method | |
CN111734318B (en) | Multifunctional hydraulic safety device for oil pipe | |
CN112343539B (en) | Hydraulic delivery steel wire salvage oil pipe inner blocking device and using method thereof | |
CN105178912A (en) | Bypass valve for drilling tools | |
CN108590576B (en) | Double-channel ball-passing type reverse check valve | |
CN108561176B (en) | Automatic blocking and permeability-increasing device and method for gas extraction drilling | |
CN210918982U (en) | Differential pressure sliding sleeve for mechanical locking and hydraulic unlocking | |
CN113513294A (en) | While-drilling water injection fracturing device and method | |
CN210859161U (en) | Hydraulic control blowout preventer for pump oil pipe | |
CN208816071U (en) | A kind of high pressure shut-in well oil-water well punching device under pressure | |
CN111734350A (en) | Separating valve capable of being opened and closed repeatedly | |
CN108222871B (en) | Safety disengaging gear for well inner pipe column | |
CN220599766U (en) | Small-diameter nonmetallic quick-drilling water injection packer | |
RU2537722C2 (en) | Hydraulic-mechanical jar | |
CN221074248U (en) | Top plate hydraulic fracturing anti-backflushing device | |
CN111622710B (en) | High-pressure activation pressure guide mechanism of sliding sleeve tool and use method | |
CN118223823A (en) | Underground test valve based on gas spring structure | |
CN113090219B (en) | Downhole blowout preventer |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
PB01 | Publication | ||
PB01 | Publication | ||
SE01 | Entry into force of request for substantive examination | ||
SE01 | Entry into force of request for substantive examination | ||
GR01 | Patent grant | ||
GR01 | Patent grant |