CN205605187U - Colliery is screen pipe fixing device for gas drainage in pit - Google Patents
Colliery is screen pipe fixing device for gas drainage in pit Download PDFInfo
- Publication number
- CN205605187U CN205605187U CN201620446200.4U CN201620446200U CN205605187U CN 205605187 U CN205605187 U CN 205605187U CN 201620446200 U CN201620446200 U CN 201620446200U CN 205605187 U CN205605187 U CN 205605187U
- Authority
- CN
- China
- Prior art keywords
- screen casing
- rod body
- main rod
- fixing device
- supporting leg
- 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.)
- Expired - Fee Related
Links
Abstract
The utility model discloses a colliery is screen pipe fixing device for gas drainage in pit, including the mobile jib body, bury the fixed leg that can follow radial direction and stretch out on the mobile jib body underground, fixed leg with be provided with the elastic component that is used for making fixed leg stretch out between the mobile jib body, a serial communication port, the one end of the mobile jib body is connected with the sieve pipe fittings of coaxial setting, can rotate relatively around the axial between the sieve pipe fittings and the mobile jib body, sieve pipe fittings's the screen pipe connecting portion of the other end for being used for the screen pipe to connect. The utility model has the advantages of simple structure, convenient operation connects reliably, and the screen pipe is by the twist -off in the time of can avoiding moving back the drilling rod to reduce collapse hole and the influence of screen pipe fracture to gas drainage, improvement gas drainage efficiency.
Description
Technical field
This utility model relates to coal mine gas drainage frock technical field, in particular to a kind of coal mine gas extraction screen casing fixing device.
Background technology
Along with the expansion of Coal Mining Scale, mining depth is continuously increased, and coal seam geological condition also becomes increasingly complex.The gas extraction hole of construction in the coal seams such as weak seam, broken coal seam, owing to coal seam is soft, poor air permeability and gas pressure big, easily occur deslagging the most freely to cause the problem such as bit freezing, burying in boring procedure；Furthermore, hole wall collapse is easily there is after weak seam Completion of Drilling Hole, that can seriously reduce drilling gas discharge-channel effectively utilizes length, and finally produce the problems such as drilling gas extraction inefficiency, extraction cycle shorten, and then do not reach the gas pumping effect that initial bore hole designs, have a strong impact on Safety of Coal Mine Production.
Collapse for boring after pore-forming and block a difficult problem for gas pumping passage, develop complete opening section and transfer screen casing gas pumping Technology.Its technical process is to ensure the unimpeded of drilling gas passage by entering gas pumping screen casing from drilling rod, drill bit endoporus after pore-forming, avoids, with this, the impact on drawing-off gas passage of collapsing of holing.But find in actual applications, on the one hand, the frictional force produced when the screen casing entered from drill pipe bore can be moved back brill is taken out of, it is impossible to ensure that screen casing is lowered at the bottom of hole completely, affect gas pumping effect；On the other hand, not being fixed at the bottom of hole by screen casing, when big-elevation of constructing wears layer gas pumping hole, screen casing can skid off in hole, have impact on safe construction, it is impossible to realizes complete opening section and transfers screen casing technique.
During construction, need again the end of screen casing to connect a fixing device being inserted into coal seam, make the end of screen casing be fixed at the bottom of hole, prevent screen casing from coming off from boring.But, during moving back brill, between screen casing and drill bit and drill pipe bore wall under frictional force effect, screen casing can rotate with drilling rod.Owing to screen casing one end has been fastened on hole wall, the other end rotates along with drilling rod, causes screen casing to be susceptible to twist off and come off.
Utility model content
For above-mentioned the deficiencies in the prior art, technical problem to be solved in the utility model is: how to provide a kind of simple in construction, easy to operate, connect reliable, can effectively prevent gas drainage under suction screen casing from being twisted off, thus reduce the collapse hole impact on gas pumping, improve the coal mine gas extraction screen casing fixing device of gas pumping efficiency.
In order to solve above-mentioned technical problem, this utility model have employed following technical scheme:
A kind of coal mine gas extraction screen casing fixing device, including main rod body, described main rod body is embedded with the fixed supporting leg that can radially stretch out, is provided with the elastic component for making fixed supporting leg stretch out between described fixed supporting leg and described main rod body；It is characterized in that, one end of described main rod body connects the screen casing connector being coaxially disposed, can be around axially opposing rotation between described screen casing connector and main rod body；The other end of described screen casing connector is the screen casing connecting portion connected for screen casing.
During work, being connected to by screen casing on screen casing connector, then fixed supporting leg is embedded in main rod body by compression elastic piece, main rod body is put in the endoporus of drilling rod, is deep at the bottom of hole with drilling rod.When moving back brill, first being drawn back slightly by drilling rod, then utilize screen casing that to direction at the bottom of hole, main rod body is released drill pipe bore, fixed supporting leg radially stretches out under the effect of elastic component and inserts coal seam, prevents screen casing from coming off from boring.Then proceeding to move back brill, screen casing rotates under the drive of drilling rod, owing to screen casing connector can rotate relative to main rod body.As such, it is possible to make screen casing entirety all rotate with drilling rod, without twisting, solve screen casing when moving back drilling rod and fix the problem that when being connected, screen casing is twisted off with fixing device.
As optimization, described screen casing connector is overall in cylinder, and has, towards one end of described main rod body, the annular boss the most outwardly formed；Described main rod body was covered towards one end fixed cover of described screen casing connector equipped with columnar connection, and described connection is covered the one end away from described main rod body and had the annular retaining ring extending inwardly in a radial direction formation；The diameter of described annular retaining ring is less than the diameter of described annular boss；The annular boss of described screen casing connector is positioned at the described cover that connects, and the other end is through the described annular retaining ring connecting cover.
So, diameter due to annular retaining ring is less than the diameter of annular boss, and annular boss is positioned at connection cover so that annular boss cannot pass from annular retaining ring, and connect cover and be fixedly set in main rod body, so that screen casing connector is connected in main rod body by connecting cover.Owing to radial direction is carried out spacing only by annular boss and annular retaining ring with being connected between cover by screen casing connector so that screen casing connector can rotate, so that screen casing connector is installed in rotation in main rod body freely relative to connecting cover.Said structure is simple, it is easy to manufacture.
As optimization, described screen casing connector is cylindrical screen casing connecting portion away from one end of described main rod body, and the described diameter of screen casing connecting portion matches with the internal diameter of screen casing, enables the connection of screen casing and described screen casing connecting portion interference fit.
During use, only need to being connected to screen casing interference fit on screen casing connecting portion, it is possible to complete the connection of screen casing and fixing device.Aforesaid operations is convenient.
As optimization, described screen casing connecting portion is away from the guide part that end is the truncated cone-shaped that diameter tapers into of described main rod body, and minimum diameter is less than the internal diameter of screen casing.
So, screen casing can be sleeved on screen casing connecting portion under the guiding function of guide part, reduces operation easier, improves screen casing and transfers efficiency.
As optimization, between the opposite face of the annular retaining ring of described connection cover and the annular boss of described screen casing connector, it is additionally provided with ball.
As such, it is possible to make sliding friction therebetween become rolling friction, be conducive to reducing abrasion therebetween, improve service life.Improve smooth rotation therebetween.
As optimization, described main rod body also having the bearing pin radially running through setting, the two ends of described bearing pin connect cover through described, make connection cover be fixed in described main rod body.
As such, it is possible to prevent the connection cover being sleeved in main rod body from coming off, improve the reliability connected.
As optimization, one end of described fixed supporting leg is arranged in described main rod body by hinge, and described hinge is arranged along the axis direction being perpendicular to described main rod body；Described fixed supporting leg is positioned at the side of hinged end and is provided with limiting section, enables described fixed supporting leg radially to fix；Described screen casing connector is connected to described main rod body one end near described fixed supporting leg folded sides.
During use, fixed supporting leg is folded towards screen casing connector place end, against main rod body, then main rod body is put in the endoporus of drilling rod, hole to be drilled put in place after, main rod body is released forward the endoporus of drilling rod, fixed supporting leg is flared out, and during moving back brill, main rod body is pulled outwardly by screen casing, make fixed supporting leg be inserted deeper into coal seam, thus main rod body is fixed at the bottom of hole.
As optimization, described main rod body has the groove of the described fixed supporting leg that can accommodate folding.As such, it is possible to reduce the volume of the fixing device after folding, conveniently fixing device is put in drill pipe bore.
As optimization, described elastic component is the torsion spring being arranged on described hinge, and described one end is connected in described main rod body, and the other end is connected to the folded sides of described fixed supporting leg.So, fixed supporting leg can be made more easily to open by torsion spring.
As optimization, described main rod body, fixed supporting leg, connects cover and screen casing connector all uses anti-electrostatic fire retardant crushibility material to make.
So, during the mechanical coal mining of later stage work face, clash into coal winning machine cutting bit and will not produce spark, improve the safety of coal mining.
In sum, the beneficial effects of the utility model are: the first, screen casing is fixing: thrust coal seam by fixed supporting leg after being opened, fixing device is fixed in boring, solves in screen casing is taken out of in hole with drilling rod under drilling rod radial frictional force effect and worn layer gas pumping hole from big-elevation the problem skidded off.The second, the anti-of screen casing twists off: be connected by rotating between screen casing connector and main rod body, when moving back brill, under drilling rod radial frictional force effect, screen casing connector rotates with drilling rod together with screen casing, and when solving to move back drilling rod, the problem that when being connected, screen casing is twisted off fixed by screen casing with fixing device.
Accompanying drawing explanation
Fig. 1 is the structural representation of this utility model one embodiment open configuration.
Fig. 2 is the structural representation of folded state in Fig. 1.
Detailed description of the invention
The utility model is described in further detail below in conjunction with the accompanying drawings.
When being embodied as, as shown in Fig. 1 ~ Fig. 2, a kind of coal mine gas extraction screen casing fixing device, including main rod body 1, it is embedded with the fixed supporting leg 2 that can radially stretch out in described main rod body 1, between described fixed supporting leg 2 and described main rod body 1, is provided with the elastic component 4 for making fixed supporting leg stretch out；One end of described main rod body 1 connects the screen casing connector 8 being coaxially disposed, can be around axially opposing rotation between described screen casing connector 8 and main rod body 1；The other end of described screen casing connector 8 is the screen casing connecting portion connected for screen casing.
During work, being connected to by screen casing on screen casing connector, then fixed supporting leg is embedded in main rod body by compression elastic piece, main rod body is put in the endoporus of drilling rod, is deep at the bottom of hole with drilling rod.When moving back brill, first being drawn back slightly by drilling rod, then utilize screen casing that to direction at the bottom of hole, main rod body is released drill pipe bore, fixed supporting leg radially stretches out under the effect of elastic component and inserts coal seam, prevents screen casing from coming off from boring.Then proceeding to move back brill, screen casing rotates under the drive of drilling rod, owing to screen casing connector can rotate relative to main rod body.As such, it is possible to make the entirety of screen casing all rotate with drilling rod, without twisting, solve screen casing when moving back drilling rod and fix the problem that when being connected, screen casing is twisted off with fixing device.
During enforcement, described screen casing connector 8 entirety is cylinder, and has, towards one end of described main rod body 1, the annular boss the most outwardly formed；Described main rod body 1 is towards one end fixed cover of described screen casing connector 8 equipped with columnar connection cover 6, and the described cover 6 that connects has the annular retaining ring extending inwardly in a radial direction formation away from one end of described main rod body 1；The diameter of described annular retaining ring is less than the diameter of described annular boss；The annular boss of described screen casing connector 8 is positioned at the described cover 6 that connects, and the other end is through the described annular retaining ring connecting cover 6.
So, diameter due to annular retaining ring is less than the diameter of annular boss, and annular boss is positioned at connection cover so that annular boss cannot pass from annular retaining ring, and connect cover and be fixedly set in main rod body, so that screen casing connector is connected in main rod body by connecting cover.Owing to radial direction is carried out spacing only by annular boss and annular retaining ring with being connected between cover by screen casing connector so that screen casing connector can rotate, so that screen casing connector is installed in rotation in main rod body freely relative to connecting cover.Said structure is simple, it is easy to manufacture.
During enforcement, described screen casing connector 8 is cylindrical screen casing connecting portion away from one end of described main rod body 1, and the described diameter of screen casing connecting portion matches with the internal diameter of screen casing, enables the connection of screen casing and described screen casing connecting portion interference fit.
During use, only need to being connected to screen casing interference fit on screen casing connecting portion, it is possible to complete the connection of screen casing and fixing device.Aforesaid operations is convenient.
During enforcement, described screen casing connecting portion is away from the guide part that end is the truncated cone-shaped that diameter tapers into of described main rod body 1, and minimum diameter is less than the internal diameter of screen casing.
So, screen casing can be sleeved on screen casing connecting portion under the guiding function of guide part, reduces operation easier, improves installation effectiveness.
During enforcement, between the opposite face of the annular retaining ring of described connection cover 6 and the annular boss of described screen casing connector 8, it is additionally provided with ball 7.The present embodiment selects ball 7, it is possible to select other to be used for tumbler in relative rotation, such as bearing etc..
As such, it is possible to make sliding friction therebetween become rolling friction, be conducive to reducing abrasion therebetween, improve service life.Improve smooth rotation therebetween.
During enforcement, described main rod body 1 also having the bearing pin 5 radially running through setting, the two ends of described bearing pin 5 pass described connection cover 6, make connection cover 6 be fixed in described main rod body 1.
As such, it is possible to prevent the connection cover being sleeved in main rod body from coming off, improve the reliability connected.
During enforcement, one end of described fixed supporting leg 2 is arranged in described main rod body 1 by hinge 3, and described hinge 3 is arranged along the axis direction being perpendicular to described main rod body 1；The side that described fixed supporting leg 2 is positioned at hinged end is provided with limiting section, makes described fixed supporting leg 2 radially to fix；Described screen casing connector 8 is connected to described main rod body 1 one end near described fixed supporting leg 2 folded sides.
During use, fixed supporting leg is folded towards screen casing connector place end, against main rod body, then main rod body is put in the endoporus of drilling rod, hole to be drilled put in place after, main rod body is released forward the endoporus of drilling rod, fixed supporting leg is flared out, and during moving back brill, main rod body is pulled outwardly by screen casing, make fixed supporting leg be inserted deeper into coal seam, thus main rod body is fixed at the bottom of hole.
During enforcement, described main rod body 1 has the groove of the described fixed supporting leg 2 that can accommodate folding.As such, it is possible to reduce the volume of the fixing device after folding, conveniently fixing device is put in drill pipe bore.
During enforcement, described elastic component 4 is the torsion spring being arranged on described hinge 3, and described one end is connected in described main rod body 1, and the other end is connected to the folded sides of described fixed supporting leg 2.So, fixed supporting leg can be made more easily to open by torsion spring.
During enforcement, described main rod body 1, fixed supporting leg 2, connects cover 6 and screen casing connector 8 all uses anti-electrostatic fire retardant crushibility material to make.
So, during the mechanical coal mining of later stage work face, clash into coal winning machine cutting bit and will not produce spark, improve the safety of coal mining.
This utility model is mainly used in weak seam and transfers screen casing engineering construction: during lower screen casing, stretch out connection cover one end by screen casing connector 8 to be connected with screen casing, enter from drill pipe bore after connection, fixing device is by under drilling rod, the constraint of drill bit pore space, elastic component 4 stress is compressed, fixed supporting leg 2 is made to fold in the groove of main rod body 1, when fixing device enters foot of hole after drilling rod and drill bit endoporus, unexpected change because of aperture, fixed supporting leg 2 opens and thrusts rib under elastic component 4 elastic force effect and is fixed, thus is fixed at the bottom of hole by screen casing；By screen casing connector 8 be connected cover 6 bottom between arrange ball 7, screen casing connector 8 can rotate relative to main rod body 1, under radial frictional force effect when moving back drilling rod, screen casing connector 8 rotates with drilling rod together with screen casing, thus when solving to move back drilling rod, screen casing twists off problem.
The foregoing is only preferred embodiment of the present utility model, not with this utility model for limiting, all any amendment, equivalent and improvement etc. made within spirit of the present utility model and principle, within should be included in protection domain of the present utility model.
Claims (10)
1. a coal mine gas extraction screen casing fixing device, including main rod body (1), it is embedded with the fixed supporting leg (2) that can radially stretch out in described main rod body (1), between described fixed supporting leg (2) and described main rod body (1), is provided with the elastic component (4) for making fixed supporting leg stretch out；It is characterized in that, one end of described main rod body (1) connects the screen casing connector (8) being coaxially disposed, can be around axially opposing rotation between described screen casing connector (8) and main rod body (1)；The other end of described screen casing connector (8) is the screen casing connecting portion connected for screen casing.
2. coal mine gas extraction screen casing fixing device as claimed in claim 1, it is characterised in that described screen casing connector (8) is overall in cylinder, and towards one end of described main rod body (1), there is the annular boss the most outwardly formed；Described main rod body (1) is towards one end fixed cover of described screen casing connector (8) equipped with the columnar cover (6) that connects, and the described cover (6) that connects has the annular retaining ring extending inwardly in a radial direction formation away from one end of described main rod body (1)；The diameter of described annular retaining ring is less than the diameter of described annular boss；The annular boss of described screen casing connector (8) is positioned at the described cover (6) that connects, and the other end is through the described annular retaining ring connecting cover (6).
3. coal mine gas extraction screen casing fixing device as claimed in claim 2, it is characterized in that, described screen casing connector (8) is cylindrical screen casing connecting portion away from one end of described main rod body (1), the described diameter of screen casing connecting portion matches with the internal diameter of screen casing, enables the connection of screen casing and described screen casing connecting portion interference fit.
4. coal mine gas extraction screen casing fixing device as claimed in claim 3, it is characterised in that described screen casing connecting portion is away from the guide part that end is the truncated cone-shaped that diameter tapers into of described main rod body (1), and minimum diameter is less than the internal diameter of screen casing.
5. coal mine gas extraction screen casing fixing device as claimed in claim 2, it is characterised in that be additionally provided with ball (7) between the opposite face of the annular retaining ring of described connection cover (6) and the annular boss of described screen casing connector (8).
6. coal mine gas extraction screen casing fixing device as claimed in claim 2, it is characterized in that, also there is in described main rod body (1) bearing pin (5) radially running through setting, the two ends of described bearing pin (5) connect cover (6) through described, make connection cover (6) be fixed in described main rod body (1).
7. coal mine gas extraction screen casing fixing device as claimed in claim 1, it is characterized in that, one end of described fixed supporting leg (2) is arranged in described main rod body (1) by hinge (3), and described hinge (3) is arranged along the axis direction being perpendicular to described main rod body (1)；Described fixed supporting leg (2) is positioned at the side of hinged end and is provided with limiting section, makes described fixed supporting leg (2) radially to fix；Described screen casing connector (8) is connected to described main rod body (1) one end near described fixed supporting leg (2) folded sides.
8. coal mine gas extraction screen casing fixing device as claimed in claim 7, it is characterised in that there is in described main rod body (1) groove of the described fixed supporting leg (2) that can accommodate folding.
9. coal mine gas extraction screen casing fixing device as claimed in claim 7, it is characterized in that, described elastic component (4) is for be arranged on the torsion spring on described hinge (3), and described one end is connected in described main rod body (1), and the other end is connected to the folded sides of described fixed supporting leg (2).
10. coal mine gas extraction screen casing fixing device as claimed in claim 2, it is characterised in that described main rod body (1), fixed supporting leg (2), connects cover (6) and screen casing connector (8) all uses anti-electrostatic fire retardant crushibility material to make.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620446200.4U CN205605187U (en) | 2016-05-17 | 2016-05-17 | Colliery is screen pipe fixing device for gas drainage in pit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620446200.4U CN205605187U (en) | 2016-05-17 | 2016-05-17 | Colliery is screen pipe fixing device for gas drainage in pit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN205605187U true CN205605187U (en) | 2016-09-28 |
Family
ID=56967820
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201620446200.4U Expired - Fee Related CN205605187U (en) | 2016-05-17 | 2016-05-17 | Colliery is screen pipe fixing device for gas drainage in pit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN205605187U (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106930735A (en) * | 2017-05-02 | 2017-07-07 | 阳泉煤业集团华越机械有限公司 | One kind can open and close type rig screen casing cap |
| CN109653722A (en) * | 2019-01-21 | 2019-04-19 | 中煤科工集团重庆研究院有限公司 | A kind of mash gas extraction device and method of coal seam hydraulic slotted liner technique and the linkage of lower screen casing |
| CN109681152A (en) * | 2018-12-11 | 2019-04-26 | 河南工程学院 | A kind of projecting coal bed aperture guard device and its screen casing pay-off method |
| CN112647877A (en) * | 2020-12-25 | 2021-04-13 | 重庆市能源投资集团科技有限责任公司 | Soft coal seam branch drilling and pipe lowering guiding device and efficient extraction method |
| CN114183075A (en) * | 2021-12-06 | 2022-03-15 | 中国矿业大学(北京) | Underground drilling-expanding-protecting integrated construction device and method |
-
2016
- 2016-05-17 CN CN201620446200.4U patent/CN205605187U/en not_active Expired - Fee Related
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106930735A (en) * | 2017-05-02 | 2017-07-07 | 阳泉煤业集团华越机械有限公司 | One kind can open and close type rig screen casing cap |
| CN109681152A (en) * | 2018-12-11 | 2019-04-26 | 河南工程学院 | A kind of projecting coal bed aperture guard device and its screen casing pay-off method |
| CN109681152B (en) * | 2018-12-11 | 2021-01-12 | 河南工程学院 | Outburst coal seam hole protection device and sieve tube lowering method thereof |
| CN109653722A (en) * | 2019-01-21 | 2019-04-19 | 中煤科工集团重庆研究院有限公司 | A kind of mash gas extraction device and method of coal seam hydraulic slotted liner technique and the linkage of lower screen casing |
| CN112647877A (en) * | 2020-12-25 | 2021-04-13 | 重庆市能源投资集团科技有限责任公司 | Soft coal seam branch drilling and pipe lowering guiding device and efficient extraction method |
| CN114183075A (en) * | 2021-12-06 | 2022-03-15 | 中国矿业大学(北京) | Underground drilling-expanding-protecting integrated construction device and method |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN205605187U (en) | Colliery is screen pipe fixing device for gas drainage in pit | |
| CN104314482B (en) | Closed type helical hole-protecting drill and using method thereof for drilling of soft coal bed | |
| CN206158642U (en) | A core draws drilling tool for prospecting | |
| CN206693921U (en) | The split type bore expanded hole drill bit of gas pumping | |
| CN101122220A (en) | Swelling type screen pipe suspension method and swelling type screen pipe hanger | |
| CN204266948U (en) | Closed spiral guard aperture drilling tool is crept into for weak seam | |
| CN209990483U (en) | Coal seam fracturing anti-reflection device | |
| CN103362449B (en) | A kind of retraction type long stroke hydraulic power pressurizer | |
| CN201258756Y (en) | Telescopic type hole packer for coal mine downhole | |
| CN206957582U (en) | Become track drilling apparatus | |
| CN103939075B (en) | A kind of fracturing process improving coal mine gas drainage effect and device | |
| CN106761443B (en) | The assembled casing of casing deformation when preventing shale gas well fracturing | |
| CN110173232B (en) | Throwing type soluble bridge plug and well cementation sliding sleeve matched with bridge plug for use | |
| CN209556988U (en) | The device of flexible screen casing under a kind of long branch's gas horizontal well suitable for weak seam | |
| CN206957611U (en) | Magnetic steering inserting tube conveying device is used in a kind of " L " type well docking | |
| CN215979337U (en) | Accurate hydraulic fracturing equipment of directional long drilling of pectination wearing layer | |
| CN205477511U (en) | Prevent releasing hydraulic fracturing hole sealing device | |
| CN105804716B (en) | A kind of method of blastingfracture extraction shale gas and swashs and split bullet | |
| CN103590791B (en) | Horizontal well perforation device | |
| CN205314949U (en) | Prevent single action assembly device that inner tube assembly drops | |
| CN203335016U (en) | Pressure bearing type grouting hole packer with pulp returning prevention device | |
| CN201144647Y (en) | Fast joint of plug-in type auger stem | |
| CN204851080U (en) | Mine high efficiency drilling rod | |
| CN207944895U (en) | A kind of telescopic setting of casing segmentation tool | |
| CN204060657U (en) | A kind of layered fracturing pipe string |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| 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: 20160928 |