CN107558940B - A kind of light-duty well repairing device in deep water hydrocarbon field and method - Google Patents
A kind of light-duty well repairing device in deep water hydrocarbon field and method Download PDFInfo
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- CN107558940B CN107558940B CN201710947176.1A CN201710947176A CN107558940B CN 107558940 B CN107558940 B CN 107558940B CN 201710947176 A CN201710947176 A CN 201710947176A CN 107558940 B CN107558940 B CN 107558940B
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Abstract
The present invention relates to a kind of light-duty well repairing device in deep water hydrocarbon field and methods, wherein, the light-duty well repairing device in deep water hydrocarbon field includes that the well workover assembly waterborne that can be connected with the loop wheel machine on working ship, the drilling rod being connected with well workover assembly waterborne and the underwater well workover assembly being connected with the lower end of drilling rod, loop wheel machine have tension and heave compensation function；Underwater well workover assembly includes sequentially connected safety joint from top to bottom, blowout prevention valve, full envelope shear ram preventer, stress joint and tieback device, and the guiding being arranged in inside stress joint is shorted；Underwater well workover assembly is connected by safety joint with drilling rod lower end, and tieback device with subsea production tree for being connected.The present invention can carry out the workover treatment in deep water hydrocarbon field using working ship, without employing large-scale floating drilling platform, can substantially reduce operating cost, improve well workover efficiency, the workover treatment of the subsea production system suitable for fixed tubular column.
Description
Technical field
The invention belongs to the light-duty well workover dresses in the underwater well workover technology field of offshore oil and gas field more particularly to a kind of deep water hydrocarbon field
It sets and method.
Background technique
It can be flat to avoid expensive offshore oil production (gas) is built using the deep water hydrocarbon field of subsea production system development mode
Platform, to save a large amount of construction investments.Increase and strata pressure after oil gas field enters mid-later development phase, with recovery percent of reserves
Decline, oil/gas well will appear various production problems, it is therefore desirable to carry out maintenance and repair to oil/gas well in process of production, and open
Open up the workover treatments such as various augmented injections, volume increase.The workover treatment of conventional subsea production system needs to connect marine riser first, pass through
Subsea production tree is connected to the well head of the water surface by marine riser；Then well workover program is basic and the workover treatment of conventional dry production tree
Program is the same.The workover treatment of conventional subsea production system, which generally requires, mobilizes semisubmersible drilling platform or drill ship, well workover
It is costly.
Summary of the invention
In view of the above-mentioned problems, the object of the present invention is to provide a kind of light-duty well repairing device in deep water hydrocarbon field and method, for
Using the deep water hydrocarbon field of subsea production system development mode, can using function relatively simple, the lower engineering of operating cost
Ship completes the workover treatment of deep water hydrocarbon well, improves well workover efficiency, reduces operating cost.
To achieve the above object, the present invention takes following technical scheme: a kind of light-duty well repairing device in deep water hydrocarbon field, special
Sign is that the device includes the well workover assembly waterborne that can be connected with the loop wheel machine on working ship and the well workover assembly phase waterborne
The drilling rod of connection and the underwater well workover assembly being connected with the lower end of the drilling rod, the loop wheel machine have tension and heave compensation function
Energy；The underwater well workover assembly include sequentially connected safety joint from top to bottom, blowout prevention valve, full envelope shear ram preventer,
Stress joint and tieback device, and the guiding being arranged in inside the stress joint are shorted；The underwater well workover assembly passes through institute
It states safety joint to be connected with the drilling rod lower end, the tieback device with subsea production tree for being connected.
The well workover assembly waterborne includes swivel head.
The well workover assembly waterborne further includes the well-repairing blowout preventor that the swivel head upper end is arranged in.
The well workover assembly waterborne further includes the decentralization short circuit that the well-repairing blowout preventor upper end is arranged in.
The stress joint uses pyramidal structure；The guiding, which is shorted, uses bell shape.
Tieback device two sides are provided with leading arm；The tieback device has hydraulic and mechanical two kinds of lockings, unlocking manners.
A kind of light-duty method for well fixing in deep water hydrocarbon field, under normal workover treatment operating condition the following steps are included:
1) the tree cap of subsea production tree is removed；
2) the fail- safe valve at closed-in well bottom and production tree produce flutter valve；
3) plug being installed in subsea production tree is taken out；
4) drilling rod connects underwater well workover assembly, and the underwater well workover assembly of tripping in；
5) make underwater well workover assembly production tree top under water, connect well workover assembly and loop wheel machine waterborne using drilling rod；
6) loop wheel machine heave compensation system is opened, continues to transfer underwater well workover assembly to subsea production tree, by water by loop wheel machine
Lower well workover assembly and subsea production tree are locked；
7) fail- safe valve is opened, guiding, tripping in workover treatment tool in Xiang Jingli oil pipe are shorted by guiding；
8) gaslift draining workover treatment or steel wire workover treatment are carried out；
9) above mention workover treatment tool to fail- safe valve upper end, close fail- safe valve, continue on lift the work of well workover out
Industry tool；
10) plug of subsea production tree is installed；
11) tieback device, Recycling of drill rod and underwater well workover assembly are freed；
12) the tree cap for installing subsea production tree, opens fail- safe valve, production tree production flutter valve, and workover treatment terminates.
Workover treatment tool in the step 7) and step 9) is coiled tubing or the underground work for carrying out steel wire operation
Tool.
It further include that emergency frees operating condition, comprising the following steps:
1. closing full envelope shear ram preventer, cuts workover treatment tool and close wellbore；
2. proposing the workover treatment tool on full envelope shear ram preventer top；
3. closing blowout prevention valve；
Drilling rod is mentioned 4. crossing, safety joint disconnects；
5. withdrawing working ship, and recycle the drilling rod of safety joint upper end.
The invention adopts the above technical scheme, which has the following advantages: 1, a kind of deep water hydrocarbon field of the invention is light
Type well repairing device and method can carry out the workover treatment in deep water hydrocarbon field using working ship, without employing large-scale floating type well drilling
Platform can substantially reduce operating cost, improve well workover efficiency.2, the light-duty well repairing device in a kind of deep water hydrocarbon field of the invention and
Method, it is quickly and reliably interim to abandon when can encounter the bad working environments such as typhoon in operation by the way that emergency disposal equipment is arranged
Well withdraws working ship, can reduce operation safety risk.3, the light-duty well repairing device in a kind of deep water hydrocarbon field of the invention and side
Method, the workover treatment of the subsea production system suitable for fixed tubular column can be widely applied to develop using subsea production system
The workover treatment in the deep water hydrocarbon field of mode.
Detailed description of the invention
Fig. 1 is structural schematic diagram of the invention；
Fig. 2 is normal operation well workover operating condition schematic diagram of the invention；
Fig. 3 is that emergency of the invention frees operating condition schematic diagram.
Specific embodiment
The present invention is described in detail below with reference to the accompanying drawings and embodiments.
As depicted in figs. 1 and 2, the light-duty well repairing device 100 in a kind of deep water hydrocarbon field provided by the invention comprising drilling rod 1,
Underwater well workover assembly 2 and well workover assembly 3 waterborne, the upper end of drilling rod 1 pass through (or the drilling well of well workover assembly 3 waterborne and working ship 200
Platform or drill ship) on loop wheel machine 300 be connected, loop wheel machine 300 should have tension and heave compensation function, for control deep water oil
The promotion and decentralization of the light-duty well repairing device 100 in gas field；Underwater well workover assembly 2 is connected with the lower end of drilling rod 1, by drilling rod 1
Mention or transfer underwater well workover assembly 2.Wherein, underwater well workover assembly 2 includes sequentially connected safety joint 21, blowout prevention from top to bottom
Valve 22, full envelope shear ram preventer 23, stress joint 24 and tieback device 25, and the guiding inside stress joint 24 is set
It is shorted 26；Underwater well workover assembly 2 is connected by safety joint 21 with the lower end of drilling rod 1, in case of emergency can be by disconnected
Safety joint 21 is opened, separates working ship 200 with the underwater well workover assembly 2 of lower part；When blowout prevention valve 22 is used in well without tubing string
Close wellbore；Full envelope shear ram preventer 23 is in case of emergency cutting off the steel wire of coiled tubing 400 or steel wire operation
It restricts or other is used for the tubing string of well workover, close wellbore；Tieback device 25 with subsea production tree 500 for being connected.
In above-described embodiment, stress joint 24 uses pyramidal structure, the moment of flexure generated for resisting the offset of working ship 200.
In above-described embodiment, 25 two sides of tieback device are provided with leading arm 27, when being easily installed by guide steel wire rope 600 with
The contraposition docking of subsea production tree 500, tieback device 25 have hydraulic and mechanical two kinds of locking unlocking manner.
In above-described embodiment, guiding is shorted 26 and uses bell shape, convenient for coiled tubing 400 when well workover or steel wire operation
Wirerope or other tubing strings for well workover pass through oil pipe 700 in well to shaft bottom.24 lower end of stress joint is provided with internal screw thread,
Guiding is shorted 26 upper ends and is provided with external screw thread, and stress joint 24 and guiding are shorted 26 and are together by a threaded connection.
In above-described embodiment, well workover assembly 3 waterborne includes swivel head 31, and swivel head 31 can overcome turning for working ship 200
It is dynamic.
In above-described embodiment, well workover assembly 3 waterborne further includes the well-repairing blowout preventor 32 that 31 upper end of swivel head is arranged in, and is used for
In workover treatment the wirerope of clamping coiled tubing 400 or steel wire operation or other be used for the tubing string of well workover, and annular space is risen
To sealing function.
In above-described embodiment, well workover assembly 3 waterborne further includes the decentralization short circuit 33 that 32 upper end of well-repairing blowout preventor is arranged in,
When workover treatment, the wirerope or other tubing strings for being used for well workover of coiled tubing 400 or steel wire operation are shorted under 33 by decentralization
It puts.
The light-duty well repairing device 100 in deep water hydrocarbon field provided in based on the above embodiment, the invention also provides a kind of depths
The light-duty method for well fixing in aqueous hydrocarbon field, the workover treatment of the subsea production system suitable for fixed tubular column comprising normal well workover is made
Industry operating condition and emergency free operating condition.
Wherein, by the gaslift of deep water gas field drain well workover for, normal workover treatment operating condition the following steps are included:
1) the tree cap that subsea production tree 500 is removed using underwater robot is placed in mud face nearby；
2) the fail- safe valve 800 at closed-in well bottom and production tree produce flutter valve 502；
3) steel wire operation takes out the plug 501 being installed in subsea production tree 500；
4) guide steel wire rope 600 is fixed on subsea production tree 500 using underwater robot, is connected with drilling rod 1 and is repaired under water
Well assembly 2 is oriented to, the underwater well workover assembly 2 of 1 tripping in of jointed rod using guide steel wire rope 600；
5) underwater well workover assembly 2 is sequentially connected swivel head using jointed rod 1 under water at 500 top 10m of production tree
31, well-repairing blowout preventor 32, decentralization are shorted 33 and loop wheel machine 300；
6) 300 heave compensation system of loop wheel machine is opened, continues to transfer underwater well workover assembly 2 to submerged production by loop wheel machine 300
Tree 500, is locked underwater well workover assembly 2 with subsea production tree 500 using underwater robot, recycles guide steel wire rope 600；
7) fail- safe valve 800 is opened, coiled tubing 400 is transferred, 26 is shorted by guiding and is directed into oil pipe 700 in well
To shaft bottom；
8) to nitrogen is injected inside coiled tubing 400, gas well plug-ging is discharged, induced flow gas well reproduces；
9) fail- safe valve 800 is closed, acts coiled tubing 400；
10) plug 501 of subsea production tree 500 is installed by steel wire operation；
11) tieback device 25, Recycling of drill rod 1 and underwater well workover assembly 2 are freed using underwater robot；
12) it using the tree cap of underwater robot installation subsea production tree 500, opens production tree and produces flutter valve 502, marine gas
Gaslift draining workover treatment in field terminates.
By taking the steel wire operation well workover of deep water hydrocarbon field as an example, normal workover treatment operating condition the following steps are included:
I~VI, with the gaslift of deep water gas field drain workover treatment when step 1)~6)；
VII, wirerope carry downhole tool and are oriented to by guiding short circuit 26, on the fail- safe valve 800 of tripping in shaft bottom
Side, wherein downhole tool includes: underground sliding bush switching tool, fishing sand tool etc., and downhole tool requires to select according to different well workovers
With；
VIII, the fail- safe valve 800 for opening shaft bottom continue to transfer downhole tool to designated position, pass through the work of carrying
Tool carries out the different workover treatments such as switching sliding sleeve or fishing sand；
IX, it acts downhole tool, closes fail- safe valve 800；
X, the plug 501 of subsea production tree 500 is installed by steel wire operation；
XI, tieback device 25, Recycling of drill rod 1 and underwater well workover assembly 2 are freed using underwater robot；
XII, the tree cap of underwater robot installation subsea production tree 500, opening fail- safe valve 800, production tree life are used
Flutter valve 502 is produced, steel wire operation well workover terminates.
If meet the bad working environments such as typhoon, interim abandoned well is needed, working ship is withdrawn.As shown in figure 3, meeting the urgent feelings such as typhoon
Emergency under condition free operating condition the following steps are included:
1. closing full envelope shear ram preventer 23, the wirerope or other use of coiled tubing 400 or steel wire operation are cut
In well workover tubing string and close wellbore；
2. proposing the coiled tubing 400 on full envelope 23 top of shear ram preventer or the wirerope of steel wire operation or other use
In the tubing string of well workover；
3. closing blowout prevention valve 22；
Drilling rod 1 is mentioned 4. crossing, safety joint 21 disconnects；
5. withdrawing working ship 200, and recycle the drilling rod 1 of 21 upper end of safety joint.
The various embodiments described above are merely to illustrate the present invention, wherein the structure of each component, setting position and its connection type etc.
It may be changed, all equivalents and improvement carried out based on the technical solution of the present invention should not arrange
In addition in protection scope of the present invention.
Claims (7)
1. a kind of light-duty well repairing device in deep water hydrocarbon field, which is characterized in that the device includes that can be connected with the loop wheel machine on working ship
The well workover assembly waterborne that connects, the drilling rod being connected with the well workover assembly waterborne and it is connected with the lower end of the drilling rod underwater
Well workover assembly, the loop wheel machine have tension and heave compensation function；The underwater well workover assembly includes being sequentially connected from top to bottom
Safety joint, blowout prevention valve, full envelope shear ram preventer, stress joint and tieback device, and be arranged in the stress joint
Internal guiding is shorted；The underwater well workover assembly is connected by the safety joint with the drilling rod lower end, the tieback
Device with subsea production tree for being connected；
The well workover assembly waterborne includes swivel head, the well-repairing blowout preventor of the swivel head upper end is arranged in, and be arranged in institute
The decentralization for stating well-repairing blowout preventor upper end is shorted.
2. a kind of light-duty well repairing device in deep water hydrocarbon field as described in claim 1, which is characterized in that the stress joint uses
Pyramidal structure；The guiding, which is shorted, uses bell shape.
3. a kind of light-duty well repairing device in deep water hydrocarbon field as described in claim 1, which is characterized in that tieback device two sides are set
It is equipped with leading arm；The tieback device has hydraulic and mechanical two kinds of lockings, unlocking manners.
4. a kind of light-duty well repairing device in deep water hydrocarbon field as claimed in claim 2, which is characterized in that tieback device two sides are set
It is equipped with leading arm；The tieback device has hydraulic and mechanical two kinds of lockings, unlocking manners.
5. a kind of light-duty method for well fixing in deep water hydrocarbon field, under normal workover treatment operating condition the following steps are included:
1) the tree cap of subsea production tree is removed；
2) the fail- safe valve at closed-in well bottom and production tree produce flutter valve；
3) plug being installed in subsea production tree is taken out；
4) drilling rod connects underwater well workover assembly, and the underwater well workover assembly of tripping in；
5) make underwater well workover assembly production tree top under water, connect well workover assembly and loop wheel machine waterborne using drilling rod；
6) loop wheel machine heave compensation system is opened, continues to transfer underwater well workover assembly to subsea production tree by loop wheel machine, will repair under water
Well assembly and subsea production tree are locked；
7) fail- safe valve is opened, guiding, tripping in workover treatment tool in Xiang Jingli oil pipe are shorted by guiding；
8) gaslift draining workover treatment or steel wire workover treatment are carried out；
9) above mention workover treatment tool to fail- safe valve upper end, close fail- safe valve, continue on lift workover operations worker out
Tool；
10) plug of subsea production tree is installed；
11) tieback device, Recycling of drill rod and underwater well workover assembly are freed；
12) the tree cap for installing subsea production tree, opens fail- safe valve, production tree production flutter valve, and workover treatment terminates.
6. a kind of light-duty method for well fixing in deep water hydrocarbon field as claimed in claim 5, which is characterized in that the step 7) and step
9) the workover treatment tool in is coiled tubing or the downhole tool for carrying out steel wire operation.
7. such as a kind of light-duty method for well fixing in deep water hydrocarbon field described in claim 5 or 6, which is characterized in that further include emergency solution
De- operating condition, comprising the following steps:
1. closing full envelope shear ram preventer, cuts workover treatment tool and close wellbore；
2. proposing the workover treatment tool on full envelope shear ram preventer top；
3. closing blowout prevention valve；
Drilling rod is mentioned 4. crossing, safety joint disconnects；
5. withdrawing working ship, and recycle the drilling rod of safety joint upper end.
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| CN201710947176.1A CN107558940B (en) | 2017-10-12 | 2017-10-12 | A kind of light-duty well repairing device in deep water hydrocarbon field and method |
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| CN201710947176.1A CN107558940B (en) | 2017-10-12 | 2017-10-12 | A kind of light-duty well repairing device in deep water hydrocarbon field and method |
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| CN107558940B true CN107558940B (en) | 2019-08-09 |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN111561299B (en) * | 2020-05-26 | 2022-05-17 | 中海石油(中国)有限公司 | Liquid drainage and gas production operation system and operation method suitable for engineering ship |
| CN112145095B (en) * | 2020-09-25 | 2022-05-17 | 中海石油(中国)有限公司 | Emergency release device and method with tie-back function |
| CN114198045B (en) * | 2021-12-03 | 2023-10-31 | 中海石油(中国)有限公司 | Inner tree cap device for shallow water underwater Christmas tree and application method thereof |
Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1447876A (en) * | 2000-08-11 | 2003-10-08 | 埃克森美孚上游研究公司 | Subsea intervention system |
| CN103261568A (en) * | 2010-08-20 | 2013-08-21 | 质量干预科学院 | Well repair |
| CN103328756A (en) * | 2010-12-13 | 2013-09-25 | 雪佛龙美国公司 | Method, system and apparatus for deployment of umbilicals in subsea well operations |
| CN105612308A (en) * | 2013-10-09 | 2016-05-25 | 国际壳牌研究有限公司 | Riserless completions |
| CN107218000A (en) * | 2017-07-27 | 2017-09-29 | 中石化石油工程机械有限公司第四机械厂 | Multi-cylinder is lifted and rotation integrated form ocean hydraulic workover unit |
| CN107503706A (en) * | 2017-10-12 | 2017-12-22 | 中国海洋石油总公司 | A kind of underwater well workover assembly |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2009067619A1 (en) * | 2007-11-20 | 2009-05-28 | Millheim Keith K | Offshore coiled tubing deployment vessel |
| US8720584B2 (en) * | 2011-02-24 | 2014-05-13 | Foro Energy, Inc. | Laser assisted system for controlling deep water drilling emergency situations |
-
2017
- 2017-10-12 CN CN201710947176.1A patent/CN107558940B/en active Active
Patent Citations (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1447876A (en) * | 2000-08-11 | 2003-10-08 | 埃克森美孚上游研究公司 | Subsea intervention system |
| CN103261568A (en) * | 2010-08-20 | 2013-08-21 | 质量干预科学院 | Well repair |
| CN103328756A (en) * | 2010-12-13 | 2013-09-25 | 雪佛龙美国公司 | Method, system and apparatus for deployment of umbilicals in subsea well operations |
| CN105612308A (en) * | 2013-10-09 | 2016-05-25 | 国际壳牌研究有限公司 | Riserless completions |
| CN107218000A (en) * | 2017-07-27 | 2017-09-29 | 中石化石油工程机械有限公司第四机械厂 | Multi-cylinder is lifted and rotation integrated form ocean hydraulic workover unit |
| CN107503706A (en) * | 2017-10-12 | 2017-12-22 | 中国海洋石油总公司 | A kind of underwater well workover assembly |
Non-Patent Citations (2)
| Title |
|---|
| 深水修井技术与装备浅谈;刘健等;《内蒙古石油化工》;20110930(第18期);第77-80页 * |
| 深水水下生产技术发展现状与展望;李清平等;《中国工程科学》;20160415;第18卷(第2期);第76-84页 * |
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