CN102392613A - Automatic splash-proof device for wellhead drilling fluid - Google Patents
Automatic splash-proof device for wellhead drilling fluid Download PDFInfo
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- CN102392613A CN102392613A CN2011103276306A CN201110327630A CN102392613A CN 102392613 A CN102392613 A CN 102392613A CN 2011103276306 A CN2011103276306 A CN 2011103276306A CN 201110327630 A CN201110327630 A CN 201110327630A CN 102392613 A CN102392613 A CN 102392613A
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Abstract
The invention relates to the technical field of drilling fluid splash-proof device for oilfield wellhead, specifically an automatic splash-proof device for wellhead drilling fluid, comprising a gas source, a gas storing tank, a one-way valve, an electric control device, an inflatable pneumatic valve, a pressure relief pneumatic valve and a three-way joint; the gas outlet of the gas source is connected with the gas inlet of the gas storing tank by a high-pressure pipeline; the gas outlet of the gas storing tank is connected with the gas inlet of the one-way valve by the high-pressure pipeline; the gas outlet of the one-way valve is connected with the gas inlet of the inflatable pneumatic valve by the high-pressure pipeline; the structure of the invention is reasonable and compact; the existing resources including gas source and power source in the well site are used; under condition that the existing single root picking operation procedure is not influenced and safety is ensured, mechatronic control system is adopted, the compressed air is used for pressing the drilling liquid in the drilling pole under the drilling platform, which brings safer and clean protection to the drilling work; the invention is featured in safety, reliability, simple and easy operation, and convenience.
Description
Technical field
the present invention relates to the anti-drilling fluid of oil field shaft mouth and spill the device technique field, are a kind of well head drilling fluid splashproof automatic device.
Background technology
In general drill-well operation process, the action need that makes up a joint when creeping into repeats
.In the operating process that makes up a joint; When dismantling screw thread; Drilling fluid in the kelly bar can come down in torrents along with the entering of air; The annular space drilling fluid can make drilling fluid overflow from drill string because of the pressure differential that cutting carring produces simultaneously, and the drilling fluid of ejection often makes on operating personnel, offshore boring island and all kinds of rig tool and spatters full drilling fluid.The working strength that the spilling of well head drilling fluid not only increased operating personnel (drilling fluid on the cleaning rig floor); It also is a serious potential safety hazard; On-the-spot main the employing be with the blowout prevention box or close down the method processing of plug valve, and the former has increased labor intensity of operating staff, and the latter has increased potential safety hazard; Realize manual well head drilling fluid anti-splash device at present, but still do not had automatic device.
Summary of the invention
the invention provides a kind of well head drilling fluid splashproof automatic device, have overcome the deficiency of above-mentioned prior art, and it can effectively solve the well head drilling fluid and spill the problem that is difficult to clear up and cause potential safety hazard.
technical scheme of the present invention realizes through following measure: a kind of well head drilling fluid splashproof automatic device comprises source of the gas, gasholder, ball-and-seat, electric control gear, inflation pneumatic operated valve, release pneumatic operated valve and threeway; The gas outlet of source of the gas is connected with the air inlet port of gasholder through pressure duct; The gas outlet of gasholder is connected with the air inlet port of ball-and-seat through pressure duct; The gas outlet of ball-and-seat is connected through the air inlet port of pressure duct with the inflation pneumatic operated valve; The gas outlet of inflation pneumatic operated valve is connected with first end of threeway through pressure duct; Second end of threeway is connected through the air inlet port of pressure duct with the release pneumatic operated valve; The 3rd end of threeway is installed with standpipe and connects pressure duct, on the pressure duct between ball-and-seat and the inflation pneumatic operated valve, is installed with first pressure transmitter, on the pressure duct between threeway and the release pneumatic operated valve, is installed with second pressure transmitter; The signal output part of first pressure transmitter is electrically connected through the signal input part of lead and electric control gear; The signal output part of second pressure transmitter is electrically connected through the signal input part of lead and electric control gear, and the signal output part of inflation pneumatic operated valve and the signal input part of electric control gear are electrically connected, and the signal output part of electric control gear is electrically connected with the signal input part of inflation pneumatic operated valve; The signal output part of release pneumatic operated valve and the signal input part of electric control gear are electrically connected, and the signal input part of the signal output part of electric control gear and release pneumatic operated valve is electrically connected.
Be to the further optimization of foregoing invention technical scheme below or/and improve:
above-mentioned standpipe connects on the pressure duct can be installed with hand-operated valve.
Can be installed with air pressurizing unit on the pressure duct between
above-mentioned source of the gas and the gasholder.
above-mentioned inflation pneumatic operated valve can be pneumatic high-voltage inflation ball valve; The release pneumatic operated valve is a pneumatic high-voltage release ball valve.
The outer end that
above-mentioned standpipe connects pressure duct can be installed with standpipe.
above-mentioned electric control gear can be PLC and HMI.
reasonable and compact in structure of the present invention; Utilize situ of drilling well existing resource such as source of the gas, power supply etc.; Not influencing the existing operational procedure and guaranteeing under the safe situation of making up a joint, adopt electromechanical integration control system, with compressed air with the drilling hydraulic in the drill string below the rig floor face; Brought more safety and clean guarantee to drilling well work, have safe and reliable, operate simple and easy, characteristics easily.
Description of drawings
accompanying drawing 1 is the structural representation of most preferred embodiment of the present invention when installing and using.
accompanying drawing 2 is the control flow block diagram of electric control gear in the accompanying drawing 1.
Coding in
accompanying drawing is respectively: 1 is source of the gas, and 2 is gasholder, and 3 is ball-and-seat, and 4 is electric control gear, and 5 are the inflation pneumatic operated valve; 6 are the release pneumatic operated valve, and 7 are threeway, and 8 is high pressure line, and 9 for standpipe connects pressure duct, and 10 is first pressure transmitter; 11 is second pressure transmitter, and 12 is hand-operated valve, and 13 is air pressurizing unit, and 14 is standpipe, and 15 is battery or well site mains lighting supply; 16 is drill string, and 17 is slush pump, and 18 is screw thread, and 19 is kelly bar, and 20 is waste liquid pool.
The specific embodiment
the present invention does not receive the restriction of following embodiment, can confirm concrete embodiment according to technical scheme of the present invention and actual conditions.
in the present invention; For the ease of describing; The description of the relative position relation of each parts all is to describe according to the Butut mode of Figure of description, as: the position relation of upper and lower, left and right etc. is what to confirm according to the Butut direction of Figure of description.
Below in conjunction with embodiment and accompanying drawing the present invention is further described:
like accompanying drawing 1, shown in 2, this well head drilling fluid splashproof automatic device comprises source of the gas 1, gasholder 2, ball-and-seat 3, electric control gear 4, inflation pneumatic operated valve 5, release pneumatic operated valve 6 and threeway 7; The gas outlet of source of the gas 1 is connected through the air inlet port of pressure duct 8 with gasholder 2; The gas outlet of gasholder 2 is connected through the air inlet port of pressure duct 8 with ball-and-seat 3; The gas outlet of ball-and-seat 3 is connected through the air inlet port of pressure duct 8 with inflation pneumatic operated valve 5; The gas outlet of inflation pneumatic operated valve 5 is connected with first end of threeway 7 through pressure duct 8; Second end of threeway 7 is connected through the air inlet port of pressure duct 8 with release pneumatic operated valve 6; The 3rd end of threeway 7 is installed with standpipe and connects pressure duct 9; On the pressure duct 8 between ball-and-seat 3 and the inflation pneumatic operated valve 5, be installed with first pressure transmitter 10; The signal output part that on the pressure duct 8 between threeway 7 and the release pneumatic operated valve 6, is installed with second pressure transmitter, 11, the first pressure transmitters 10 is electrically connected through the signal input part of lead and electric control gear 4, and the signal output part of second pressure transmitter 11 is electrically connected through the signal input part of lead and electric control gear 4; The signal output part of inflation pneumatic operated valve 5 and the signal input part of electric control gear 4 are electrically connected, and the signal output part of electric control gear 4 is electrically connected with the signal input part of inflation pneumatic operated valve 5; The signal input part of the signal output part of release pneumatic operated valve 6 and electric control gear 4 is electrically connected, and the signal input part of the signal output part of electric control gear 4 and release pneumatic operated valve 6 is electrically connected.Wherein, electric control gear 4 is existing known various control device.
Can according to actual needs above-mentioned well head drilling fluid splashproof automatic device be done further to optimize or/and improve:
are installed with hand-operated valve 12 on standpipe connection pressure duct 9 shown in accompanying drawing 1.Like this, being convenient to when meeting accident can manual-lock hand-operated valve 12, and well head drilling fluid splashproof automatic device and drilling rig are broken away from.
are installed with air pressurizing unit 13 on the pressure duct 8 between source of the gas 1 and the gasholder 2 shown in accompanying drawing 1.
shown in accompanying drawing 1, as required, inflation pneumatic operated valve 5 is pneumatic high-voltage inflation ball valve; Release pneumatic operated valve 6 is a pneumatic high-voltage release ball valve.
shown in accompanying drawing 1, the outer end that standpipe connects pressure duct 9 is installed with standpipe 14.
shown in accompanying drawing 1, electric control gear 4 is PLC and HMI.Wherein PLC is existing known programmable logic controller (PLC), and HMI is a man-machine interface.
above technical characterictic has constituted most preferred embodiment of the present invention, and it has stronger compliance and best implementation result, can increase and decrease non-essential technical characterictic according to actual needs, satisfies the demand of different situations.
The operating principle and the use of
most preferred embodiment of the present invention: the Compressed Gas that the source of the gas 1 in well site provides is stored in the gasholder 2 after air pressurizing unit 13 superchargings, makes gasholder 2 pressure reach required pressure.Gas in the gasholder 2 is through ball-and-seat 3 outputs of protection usefulness, and the pressure size is measured by first pressure transmitter 10 and is sent to electric control gear 4.Inflation pneumatic operated valve 5 is pneumatic high-voltage inflation ball valve; Release pneumatic operated valve 6 is a pneumatic high-voltage release ball valve, and the required source of the gas of its pneumatic actuator is also provided by the well site source of the gas, is opened and closed by electric control gear 4 controls.Hand-operated valve 12 has the safeguard protection effect, can manual-lock when meeting accident, and make device break away from drilling rig.Release pneumatic operated valve 6 and waste liquid pool 20 UNICOMs, the release that is used for gas, drilling fluid mixed thing is discharged, and the pressure during release is kept watch on by second pressure transmitter 11.Electric control gear 4 is made up of PLC (programmable logic controller (PLC)) and HMI (man-machine interface), through the pressure that first pressure transmitter 10 and second pressure transmitter 11 are measured everywhere, accomplishes valve operation through the electromagnetic valve of pneumatic actuator.All manually reach to operate automatically and be provided with all and realize through the touch-screen of HMI.
When use
, battery or connection well site mains lighting supply 15 are installed at first for electric control gear 4, after slush pump 17 terminations of pumping; Open inflation pneumatic operated valve 5, Compressed Gas injects the up water tap that leads in back from the joint of standpipe 14, and the drilling fluid that drives then in the drill string 16 is descending; After the drilling fluid liquid level goes downwards to the appropriate location, close inflation pneumatic operated valve 5, open 6 releases of release pneumatic operated valve; After release is accomplished, just can dismantle screw thread 18 and make up a joint.Because need bigger pressure ability fast driving drilling fluid descending, therefore after drilling fluid arrived correct position, the gas pressure in the kelly bar 19 was still bigger, needed release could dismantle screw thread 18 safely.In this device, use Mechano-electrically integrated control unit, all valve operations all can manually also can carry out automatically.For automatic operating process, shown in accompanying drawing 2: 1, before the operation that makes up a joint, the driller presses the startup button.System gets into operation automatically.2, system detects standpipe 14 pressure less than setting pressure, opens 5 inflations of inflation pneumatic operated valve automatically.3, reach setting pressure or overtime when inflation, close inflation pneumatic operated valve 5, open 6 releases of release pneumatic operated valve.4, be reduced to setting value or overtime when pressure, close release pneumatic operated valve 6.5, light safety and unload an indicator lamp, once-through operation is accomplished.Automatically reaching in the manual operation, can press stop button at any time and stop each generic operation, pressing stop button, inflation pneumatic operated valve 5 and release pneumatic operated valve 6 all automatically shut down.After once operating automatically normally, system automatically resets and waits for next the operation.
Claims (10)
1. a well head drilling fluid splashproof automatic device is characterized in that comprising source of the gas, gasholder, ball-and-seat, electric control gear, inflation pneumatic operated valve, release pneumatic operated valve and threeway; The gas outlet of source of the gas is connected with the air inlet port of gasholder through pressure duct; The gas outlet of gasholder is connected with the air inlet port of ball-and-seat through pressure duct; The gas outlet of ball-and-seat is connected through the air inlet port of pressure duct with the inflation pneumatic operated valve; The gas outlet of inflation pneumatic operated valve is connected with first end of threeway through pressure duct; Second end of threeway is connected through the air inlet port of pressure duct with the release pneumatic operated valve; The 3rd end of threeway is installed with standpipe and connects pressure duct, on the pressure duct between ball-and-seat and the inflation pneumatic operated valve, is installed with first pressure transmitter, on the pressure duct between threeway and the release pneumatic operated valve, is installed with second pressure transmitter; The signal output part of first pressure transmitter is electrically connected through the signal input part of lead and electric control gear; The signal output part of second pressure transmitter is electrically connected through the signal input part of lead and electric control gear, and the signal output part of inflation pneumatic operated valve and the signal input part of electric control gear are electrically connected, and the signal output part of electric control gear is electrically connected with the signal input part of inflation pneumatic operated valve; The signal output part of release pneumatic operated valve and the signal input part of electric control gear are electrically connected, and the signal input part of the signal output part of electric control gear and release pneumatic operated valve is electrically connected.
2. well head drilling fluid splashproof automatic device according to claim 1 is characterized in that being installed with hand-operated valve on the standpipe connection pressure duct.
3. well head drilling fluid splashproof automatic device according to claim 1 and 2 is characterized in that being installed with air pressurizing unit on the pressure duct between source of the gas and the gasholder.
4. well head drilling fluid splashproof automatic device according to claim 1 and 2, it is characterized in that inflating pneumatic operated valve is pneumatic high-voltage inflation ball valve; The release pneumatic operated valve is a pneumatic high-voltage release ball valve.
5. well head drilling fluid splashproof automatic device according to claim 3, it is characterized in that inflating pneumatic operated valve is pneumatic high-voltage inflation ball valve; The release pneumatic operated valve is a pneumatic high-voltage release ball valve.
6. well head drilling fluid splashproof automatic device according to claim 1 and 2 is characterized in that the outer end of standpipe connection pressure duct is installed with standpipe.
7. well head drilling fluid splashproof automatic device according to claim 3 is characterized in that the outer end of standpipe connection pressure duct is installed with standpipe.
8. well head drilling fluid splashproof automatic device according to claim 5 is characterized in that the outer end of standpipe connection pressure duct is installed with standpipe.
9. well head drilling fluid splashproof automatic device according to claim 1 and 2 is characterized in that electric control gear is PLC and HMI.
10. well head drilling fluid splashproof automatic device according to claim 8 is characterized in that electric control gear is PLC and HMI.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103276306A CN102392613A (en) | 2011-10-25 | 2011-10-25 | Automatic splash-proof device for wellhead drilling fluid |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN2011103276306A CN102392613A (en) | 2011-10-25 | 2011-10-25 | Automatic splash-proof device for wellhead drilling fluid |
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| CN102392613A true CN102392613A (en) | 2012-03-28 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN2011103276306A Pending CN102392613A (en) | 2011-10-25 | 2011-10-25 | Automatic splash-proof device for wellhead drilling fluid |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102704908A (en) * | 2012-05-14 | 2012-10-03 | 西南石油大学 | Split-flow automatic control system of coal bed methane horizontal branch well and process thereof |
| CN102865046A (en) * | 2012-09-13 | 2013-01-09 | 东营天华石油技术开发有限公司 | Fluid anti-splash device for buckling lead-in of oil pipe in mechanical operation under pressure and use method thereof |
| CN103352669A (en) * | 2013-07-23 | 2013-10-16 | 四川宏华石油设备有限公司 | Recycling device of mud generated during well drilling and well repairing |
| CN107208469A (en) * | 2015-01-30 | 2017-09-26 | 海德里尔美国配送有限责任公司 | Reduce the BOP control system loop of flow of pressurized/water hammer |
| CN110107248A (en) * | 2019-05-31 | 2019-08-09 | 宝鸡石油机械有限责任公司 | A kind of spray arrester control device and its method of controlling security |
| CN112049600A (en) * | 2020-09-29 | 2020-12-08 | 中油国家油气钻井装备工程技术研究中心有限公司 | Slurry blowout prevention box control system and control method |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1155613A (en) * | 1996-01-22 | 1997-07-30 | 中原石油勘探局钻井总公司 | Method of nozzling while drilling with controllable negative pressure and apparatus thereof |
| GB2327442A (en) * | 1997-07-17 | 1999-01-27 | Jeffrey Reddoch | Modular system and method for processing and injecting oil and gas drill cuttings |
| US5890549A (en) * | 1996-12-23 | 1999-04-06 | Sprehe; Paul Robert | Well drilling system with closed circulation of gas drilling fluid and fire suppression apparatus |
| CN201843543U (en) * | 2010-11-15 | 2011-05-25 | 中国石油集团西部钻探工程有限公司 | Device for preventing wellhead drilling fluid from splashing |
| CN202012329U (en) * | 2011-02-10 | 2011-10-19 | 天合石油集团汇丰石油装备股份有限公司 | Mud anti-splashing valve for kelly bar |
| CN202249860U (en) * | 2011-10-25 | 2012-05-30 | 中国石油集团西部钻探工程有限公司 | Splash-proof automatic device for wellhead drilling fluid |
-
2011
- 2011-10-25 CN CN2011103276306A patent/CN102392613A/en active Pending
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1155613A (en) * | 1996-01-22 | 1997-07-30 | 中原石油勘探局钻井总公司 | Method of nozzling while drilling with controllable negative pressure and apparatus thereof |
| US5890549A (en) * | 1996-12-23 | 1999-04-06 | Sprehe; Paul Robert | Well drilling system with closed circulation of gas drilling fluid and fire suppression apparatus |
| GB2327442A (en) * | 1997-07-17 | 1999-01-27 | Jeffrey Reddoch | Modular system and method for processing and injecting oil and gas drill cuttings |
| CN201843543U (en) * | 2010-11-15 | 2011-05-25 | 中国石油集团西部钻探工程有限公司 | Device for preventing wellhead drilling fluid from splashing |
| CN202012329U (en) * | 2011-02-10 | 2011-10-19 | 天合石油集团汇丰石油装备股份有限公司 | Mud anti-splashing valve for kelly bar |
| CN202249860U (en) * | 2011-10-25 | 2012-05-30 | 中国石油集团西部钻探工程有限公司 | Splash-proof automatic device for wellhead drilling fluid |
Non-Patent Citations (1)
| Title |
|---|
| 胡永建等: "一种新型接钻具钻井液防溅装置", 《石油矿场机械》 * |
Cited By (11)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102704908A (en) * | 2012-05-14 | 2012-10-03 | 西南石油大学 | Split-flow automatic control system of coal bed methane horizontal branch well and process thereof |
| CN102865046A (en) * | 2012-09-13 | 2013-01-09 | 东营天华石油技术开发有限公司 | Fluid anti-splash device for buckling lead-in of oil pipe in mechanical operation under pressure and use method thereof |
| CN102865046B (en) * | 2012-09-13 | 2014-11-26 | 东营天华石油技术开发有限公司 | Fluid anti-splash device for buckling lead-in of oil pipe in mechanical operation under pressure and use method thereof |
| CN103352669A (en) * | 2013-07-23 | 2013-10-16 | 四川宏华石油设备有限公司 | Recycling device of mud generated during well drilling and well repairing |
| CN103352669B (en) * | 2013-07-23 | 2015-12-16 | 四川宏华石油设备有限公司 | A kind of drilling and repairing well Mud reclamation device |
| CN107208469A (en) * | 2015-01-30 | 2017-09-26 | 海德里尔美国配送有限责任公司 | Reduce the BOP control system loop of flow of pressurized/water hammer |
| CN107208469B (en) * | 2015-01-30 | 2020-11-13 | 海德里尔美国配送有限责任公司 | BOP control system loop for reducing hydraulic flow/water hammer |
| CN110107248A (en) * | 2019-05-31 | 2019-08-09 | 宝鸡石油机械有限责任公司 | A kind of spray arrester control device and its method of controlling security |
| CN110107248B (en) * | 2019-05-31 | 2021-10-15 | 宝鸡石油机械有限责任公司 | Slurry blowout prevention box control device and safety control method thereof |
| CN112049600A (en) * | 2020-09-29 | 2020-12-08 | 中油国家油气钻井装备工程技术研究中心有限公司 | Slurry blowout prevention box control system and control method |
| CN112049600B (en) * | 2020-09-29 | 2022-12-09 | 中油国家油气钻井装备工程技术研究中心有限公司 | Mud blowout prevention box control system and control method |
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Application publication date: 20120328 |