CN113833918A - Lining structure of high-pressure water injection composite pipeline in oil field - Google Patents
Lining structure of high-pressure water injection composite pipeline in oil field Download PDFInfo
- Publication number
- CN113833918A CN113833918A CN202110992641.XA CN202110992641A CN113833918A CN 113833918 A CN113833918 A CN 113833918A CN 202110992641 A CN202110992641 A CN 202110992641A CN 113833918 A CN113833918 A CN 113833918A
- Authority
- CN
- China
- Prior art keywords
- lining
- flange
- pipeline
- flanging
- water injection
- 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.)
- Pending
Links
- 239000002131 composite material Substances 0.000 title claims abstract description 22
- 238000002347 injection Methods 0.000 title claims abstract description 19
- 239000007924 injection Substances 0.000 title claims abstract description 19
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 19
- 238000007789 sealing Methods 0.000 claims abstract description 38
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 34
- 239000010959 steel Substances 0.000 claims abstract description 34
- 238000003466 welding Methods 0.000 claims abstract description 24
- -1 polytetrafluoroethylene Polymers 0.000 claims abstract description 21
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims abstract description 21
- 239000004810 polytetrafluoroethylene Substances 0.000 claims abstract description 21
- 239000004699 Ultra-high molecular weight polyethylene Substances 0.000 claims description 8
- 229920000785 ultra high molecular weight polyethylene Polymers 0.000 claims description 8
- 238000005242 forging Methods 0.000 claims description 2
- 238000005516 engineering process Methods 0.000 abstract description 4
- 238000003912 environmental pollution Methods 0.000 abstract description 3
- 230000006835 compression Effects 0.000 abstract 2
- 238000007906 compression Methods 0.000 abstract 2
- 239000003921 oil Substances 0.000 description 11
- 238000000034 method Methods 0.000 description 8
- 238000003825 pressing Methods 0.000 description 6
- 230000007797 corrosion Effects 0.000 description 5
- 238000005260 corrosion Methods 0.000 description 5
- 239000010410 layer Substances 0.000 description 4
- 238000004519 manufacturing process Methods 0.000 description 3
- 229920010741 Ultra High Molecular Weight Polyethylene (UHMWPE) Polymers 0.000 description 2
- 239000010779 crude oil Substances 0.000 description 2
- 241000894006 Bacteria Species 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000005536 corrosion prevention Methods 0.000 description 1
- 230000006735 deficit Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000003628 erosive effect Effects 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 231100000252 nontoxic Toxicity 0.000 description 1
- 230000003000 nontoxic effect Effects 0.000 description 1
- 239000002332 oil field water Substances 0.000 description 1
- 239000003129 oil well Substances 0.000 description 1
- 230000035515 penetration Effects 0.000 description 1
- 238000011084 recovery Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L23/00—Flanged joints
- F16L23/16—Flanged joints characterised by the sealing means
- F16L23/18—Flanged joints characterised by the sealing means the sealing means being rings
- F16L23/22—Flanged joints characterised by the sealing means the sealing means being rings made exclusively of a material other than metal
-
- 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
- E21B43/00—Methods or apparatus for obtaining oil, gas, water, soluble or meltable materials or a slurry of minerals from wells
- E21B43/16—Enhanced recovery methods for obtaining hydrocarbons
- E21B43/20—Displacing by water
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
- F16L23/00—Flanged joints
- F16L23/02—Flanged joints the flanges being connected by members tensioned axially
- F16L23/036—Flanged joints the flanges being connected by members tensioned axially characterised by the tensioning members, e.g. specially adapted bolts or C-clamps
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (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)
- Flanged Joints, Insulating Joints, And Other Joints (AREA)
Abstract
The invention discloses a lining structure for a water injection composite pipeline on the ground of an oil field, which mainly comprises a steel pipeline, a neck-equipped concave-butt welding flange, a lining pipe, a flanging lining, a limiting ring, a polytetrafluoroethylene sealing ring and a bolt fastener, wherein the lining pipe with the outer diameter slightly larger than the inner wall of the steel pipe is embedded into the inner wall of the steel pipe by adopting an equal-diameter compression technology, the lining at the joint is pressed into a flange shape by adopting a high-temperature compression device, and the flange is tightly attached to the end face of the neck-equipped concave-butt welding flange. The thickness of the flanging lining is smaller than the depth of the groove of the flange, and the polytetrafluoroethylene sealing ring is embedded into the groove, so that the lining and the sealing ring are jointly pressed and sealed under the action of the pre-tightening force of the bolt. And finally, one end of the limiting ring is welded on the end face of the flange, the other end of the limiting ring is attached to the end face of the flange on the other side under the action of the pre-tightening force of the bolt, and the lining connecting structure is locked, positioned and sealed, so that the overall mechanical property of the pipeline is greatly improved, the economic cost is reduced, and the problem of environmental pollution is solved.
Description
Technical Field
The invention relates to a lining connection anticorrosion structure for a high-pressure water injection ground pipeline in an oil field, which can effectively solve the problem of water inflow of a lining and a steel pipe interlayer, greatly improve the anticorrosion performance and the pressure resistance of the pipeline and provide reference for the application of a composite pipeline in practical engineering.
Background
After the oil field is put into development, the energy of the oil layer is continuously consumed along with the increase of the exploitation time, so that the pressure of the oil layer is continuously reduced, underground crude oil is greatly degassed, the viscosity is increased, the yield of the oil well is greatly reduced, even the injection and production stop can be realized, and a large amount of underground residual dead oil cannot be extracted. In order to make up for the underground deficit caused by the production of crude oil, maintain or improve the pressure of an oil layer, realize high and stable yield of an oil field and obtain higher recovery ratio, water must be injected into the oil field.
A ground pipeline for carrying oil field water injection generally adopts the steel and does not have interior tubular product of preventing, has the perforation problem of corruption, causes very big influence to production, can cause environmental pollution simultaneously. The corrosion prevention and joint coating technology in the water injection pipeline has the problems of no erosion resistance, no pressure resistance, easy brittle fracture, pinhole effect, difficult control of construction quality, high cost and the like. Therefore, the lining inserting technology is adopted to embed the lining with high strength, low density, high wear resistance, long service life and corrosion resistance into the single steel pipe to form a structural composite pipe with the steel pipe, the external steel pipe plays a role in bearing pressure, and the lining pipe plays roles in internal corrosion resistance, wear resistance and the like.
The lining strength in the composite pipeline is low, in a high-pressure flow transmission pipeline, the vibration damage at the joint of the composite pipeline is most obvious due to unstable pressure or unstable flow speed, and the lining structure at the joint needs to have sufficient strength and tightness in the practical application process.
Disclosure of Invention
In order to ensure that the lining joint of the high-pressure water injection composite pipeline has better sealing property and strength, the invention designs a lining sealing structure for the connection of a high-pressure water injection flange of an oil field. The problem of inside lining, steel pipe intermediate layer intake is solved, the corrosion resisting property and the compressive capacity of pipeline have been improved greatly, economic cost has been reduced, environmental pollution has been reduced, the life of whole pipeline has been improved.
The design structure mainly comprises a steel pipeline 1, a neck butt welding concave flange 2, an inner lining pipe 3, a flanging lining 4, a limiting ring 5, a sealing ring 6 and a bolt fastener 7. Both side parts of the steel pipeline 1 are fixed by neck butt welding concave flanges 2, the inner walls of the steel pipeline 1 and the neck butt welding concave flanges 2 are lining pipes 3, and the two neck butt welding concave flanges 2 are connected through a flanging lining 4; the end part of the flanging lining 4 is provided with a limiting ring 5 and is installed and fixed by a sealing ring 6 and a bolt fastener 7.
The steel pipeline 1 and the neck butt welding flange 2 are made of 20# steel, the lining pipe 3 and the flanging lining 4 are made of ultra-high molecular weight polyethylene (UHMWPE) with high strength, low density and excellent corrosion resistance, the limiting ring is made of A106 tubular products or customized forgings, and the sealing ring is made of polytetrafluoroethylene with excellent sealing performance.
The steel pipeline 1 is connected with a neck butt welding concave flange 2 in a welding mode, an UHMWPE lining pipe 3 with the diameter slightly larger than the inner wall of the steel pipe is temporarily reduced and pulled in by a tractor, a section of length is reserved at the end part of the lining pipe, the lining pipe is pressed into a flange shape by a special high-temperature pressing device, and the flange and the steel flange form a composite flange.
The neck butt welding concave flange 2 adopts the concave surface to carry out sealing connection, and the concave surface thickness is big than turn-ups inside lining 4 thickness, with 6 imbeds the concave surface of polytetrafluoroethylene sealing ring, with the common pressure-bearing of inside lining. The diameter of the concave surface is slightly larger than that of the turned-over edge lining 4, so that stress concentration cannot occur in the pressing process, and the lining is prevented from being crushed.
The polytetrafluoroethylene sealing element is made into a ring shape, the outer diameter of the polytetrafluoroethylene sealing ring 6 is slightly smaller than the diameter of the concave surface of the neck butt welding flange 2, and stress concentration cannot be caused under the action of bolt pre-tightening force. The inner diameter of the sealing ring 6 is the same as that of the lining pipe 3.
The inner diameter of the limiting ring 5 is 1-2 mm larger than the outer diameter of the polytetrafluoroethylene sealing ring, and sliding is avoided in the pressing process. The thickness of the limiting ring is slightly smaller than that of the exposed part of the polytetrafluoroethylene, so that after the liner and the sealing ring are compressed and deformed, the other end of the limiting ring 5 is compressed with the flange on the other side, and the positioning and locking functions are achieved.
The integral composite pipeline is good in integrity, and the lining structure at the joint has good sealing performance and meets the connection requirement.
Drawings
FIG. 1 is a cross-sectional view of a composite pipeline in elevation
Fig. 2 is a right side view of the composite pipeline.
FIG. 3 is a cross-sectional view in elevation of the liner tube.
FIG. 4 is a front view of a polytetrafluoroethylene sealing ring.
FIG. 5 is a front view of the stop collar.
In the figure: 1. the steel-pipe line, 2, take neck butt welding concave flange, 3, inside lining pipe, 4, turn-ups inside lining, 5, spacing ring, 6, sealed dish, 7, bolt fastener.
Detailed Description
The invention is further described with reference to the following figures and detailed description.
As shown in figure 1, the lining structure at the joint of the high-pressure water injection composite pipeline in the oil field comprises a steel pipeline 1, a neck-butt-welding concave flange 2, a lining pipe 3, a flanging lining 4, a limiting ring 5, a sealing ring 6 and a bolt fastener 7. The steel pipeline 1 is welded with the welding flange 2 with the neck, the outer diameter of the flanging lining 4 is larger than the inner diameter of the steel pipeline 1, an isometric compressor is adopted, the diameter of the lining pipe 2 is temporarily reduced, the lining pipe 3 is pulled into the pipe by a tractor, and the steel pipeline is pressed or attached to the inner wall of the steel pipe by depending on the self-resilience characteristic.
As shown in the combined drawings 1 and 3, the flanging thickness of the joint of the lining pipe is slightly smaller than the depth of the concave flange, the polytetrafluoroethylene sealing ring 6 is embedded into the concave flange, the flanging lining and the polytetrafluoroethylene sealing ring are guaranteed to bear pressure and seal together under the action of the pre-tightening force of the bolt, and the sealing performance is guaranteed.
As shown in figure 4, the polytetrafluoroethylene 6 is made into a ring shape, the outer diameter of the sealing ring is 2-3 mm smaller than that of the concave surface, and the pressing deformation process is guaranteed not to be crushed.
As shown in figures 1, 2 and 5, one end of the limiting ring 5 is welded with the end face of the concave flange, and the inner diameter of the limiting ring 5 is 1-2 mm larger than the outer diameter of the polytetrafluoroethylene sealing ring, so that slippage is avoided in the pressing process. The thickness of the limiting ring is slightly smaller than that of the exposed part of the polytetrafluoroethylene, so that after the liner and the sealing ring are compressed and deformed, the other end of the limiting ring 5 is compressed with the flange on the other side, and the positioning and locking functions are achieved.
The technical principle of lining penetration is as follows: the UHMWPE lining is embedded into a single steel pipeline by adopting a process of inserting an ultrahigh molecular weight polyethylene (UHMWPE) pipe. The UHMWPE pipe has excellent chemical stability, corrosion resistance, wear resistance, temperature resistance, long service life, ultralow friction resistance and the like, and the inner wall of the UHMWPE pipe is smooth, is not easy to scale, is nontoxic and does not breed bacteria. The method comprises the following steps: the method comprises the steps of selecting a proper lining UHMWPE pipe 3, reducing the diameter of the pipe, pulling the pipe into a steel pipeline 1 under the action of certain traction force, and enabling the lining pipe 3 to recover the original physical form under the action of certain external force by adopting a special technology to be tightly attached to the inner wall of an outer steel pipe to form a pipe-in-pipe structure. And a special high-temperature pressing device is adopted to compress the redundant lining pipe into a flange shape, the flange shape is tightly attached to the concave surface of the welding flange with the neck, and the flanging lining 4 and the polytetrafluoroethylene sealing ring 6 are jointly pressed and sealed under the action of the pretightening force of the bolt. The limiting ring locks the exposed part of the polytetrafluoroethylene sealing ring 6 to ensure that the polytetrafluoroethylene sealing ring does not slide. The composite pipeline structure has the comprehensive performance of a steel pipe and an UHMWPE pipe, has good strength, sealing performance and structural stability, and greatly prolongs the service life of a pipeline.
Claims (8)
1. Oil field high pressure water injection composite line inside lining structure, its characterized in that: the device comprises a steel pipeline (1), a neck butt welding concave flange (2), a lining pipe (3), a flanging lining (4), a limiting ring (5), a sealing ring (6) and a bolt fastener (7); both side parts of the steel pipeline (1) are fixed by neck butt welding concave flanges (2), the inner walls of the steel pipeline (1) and the neck butt welding concave flanges (2) are lining pipes (3), and the two neck butt welding concave flanges (2) are connected through a flanging lining (4); the end part of the flanging lining (4) is provided with a limiting ring (5) and is fixedly installed by a sealing ring (6) and a bolt fastener (7).
2. The oilfield high pressure water injection composite pipeline lining structure of claim 1, wherein: the steel pipeline (1) and the neck butt-welding concave flange (2) both adopt 20# steel, the lining pipe (3) and the flanging lining (4) adopt ultrahigh molecular weight polyethylene, the limiting ring (5) adopts A106 tubular product or customized forging, and the sealing ring is made of polytetrafluoroethylene with excellent sealing performance.
3. The oilfield high pressure water injection composite pipeline lining structure of claim 1, wherein: the steel pipeline (1) is connected with the neck butt welding concave flange (2) in a welding mode, the lining pipe (3) with the diameter slightly larger than the inner wall of the steel pipe is temporarily reduced, and the lining pipe is pulled in by a tractor.
4. The oilfield high pressure water injection composite pipeline lining structure of claim 1, wherein: the neck butt welding concave flange (2) is hermetically connected by adopting a concave surface, the thickness of the concave surface is larger than that of the flanging lining (4), and the sealing ring (6) is embedded into the concave surface and bears pressure together with the lining; the diameter of the concave surface is larger than that of the flanging lining (4).
5. The oilfield high pressure water injection composite pipeline lining structure of claim 1, wherein: the outer diameter of the sealing ring (6) is smaller than the diameter of the concave surface of the neck butt welding concave flange (2); the inner diameter of the sealing ring (6) is the same as that of the lining pipe (3).
6. The oilfield high pressure water injection composite pipeline lining structure of claim 1, wherein: the inner diameter of the limiting ring (5) is 1-2 mm larger than the outer diameter of the polytetrafluoroethylene sealing ring; the thickness of the limiting ring is smaller than that of the exposed part of the polytetrafluoroethylene.
7. The oilfield high pressure water injection composite pipeline lining structure of claim 1, wherein: under the condition of high-pressure water injection, the flanging lining (4) is guaranteed to be tightly pressed with the polytetrafluoroethylene sealing ring (6) under the action of bolt pre-tightening force, and the limiting ring locks the flanging lining.
8. The oilfield high pressure water injection composite pipeline lining structure of claim 1, wherein: the ultra-high molecular weight polyethylene lining pipe (3) is pulled into the steel pipe under the action of a tractor, and is tightly attached to the inner wall of the pipeline in a pressurizing mode, the diameter of the flanging lining is smaller than that of the concave surface of the flange, and the thickness of the flanging is smaller than that of the concave surface of the flange.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110992641.XA CN113833918A (en) | 2021-08-27 | 2021-08-27 | Lining structure of high-pressure water injection composite pipeline in oil field |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110992641.XA CN113833918A (en) | 2021-08-27 | 2021-08-27 | Lining structure of high-pressure water injection composite pipeline in oil field |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN113833918A true CN113833918A (en) | 2021-12-24 |
Family
ID=78961488
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110992641.XA Pending CN113833918A (en) | 2021-08-27 | 2021-08-27 | Lining structure of high-pressure water injection composite pipeline in oil field |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113833918A (en) |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3216745A (en) * | 1962-02-16 | 1965-11-09 | Lummus Nederland N V | Flange coupling and method for assembling the same |
| EP0100580A1 (en) * | 1982-08-02 | 1984-02-15 | The Dow Chemical Company | Plastic lined pipe joint and method of joining |
| CN2849411Y (en) * | 2005-05-27 | 2006-12-20 | 康庆刚 | Flange jointed teflon liner pipeline, bend and three-way reducing pipe |
| CN201339768Y (en) * | 2008-12-12 | 2009-11-04 | 煌盛集团有限公司 | Composite pipe internally lined with ultra-high molecular weight polyethylene pipe |
| CN201561199U (en) * | 2009-12-17 | 2010-08-25 | 河北金菱管业股份有限公司 | Mining wear-resistant steel-plastic composite pipeline |
| CN204785307U (en) * | 2015-05-07 | 2015-11-18 | 山东柯林瑞尔管道工程有限公司 | Anticorrosive plastic tubing pipeline of inside lining |
| CN205877497U (en) * | 2016-06-27 | 2017-01-11 | 永嘉县特富隆防腐设备有限公司 | High strength tetrafluoro inside lining pipe joint |
| CN206708600U (en) * | 2017-03-07 | 2017-12-05 | 河南中拓石油工程技术股份有限公司 | A kind of outer fixed ring type HDPE Flange attachment means |
-
2021
- 2021-08-27 CN CN202110992641.XA patent/CN113833918A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3216745A (en) * | 1962-02-16 | 1965-11-09 | Lummus Nederland N V | Flange coupling and method for assembling the same |
| EP0100580A1 (en) * | 1982-08-02 | 1984-02-15 | The Dow Chemical Company | Plastic lined pipe joint and method of joining |
| CN2849411Y (en) * | 2005-05-27 | 2006-12-20 | 康庆刚 | Flange jointed teflon liner pipeline, bend and three-way reducing pipe |
| CN201339768Y (en) * | 2008-12-12 | 2009-11-04 | 煌盛集团有限公司 | Composite pipe internally lined with ultra-high molecular weight polyethylene pipe |
| CN201561199U (en) * | 2009-12-17 | 2010-08-25 | 河北金菱管业股份有限公司 | Mining wear-resistant steel-plastic composite pipeline |
| CN204785307U (en) * | 2015-05-07 | 2015-11-18 | 山东柯林瑞尔管道工程有限公司 | Anticorrosive plastic tubing pipeline of inside lining |
| CN205877497U (en) * | 2016-06-27 | 2017-01-11 | 永嘉县特富隆防腐设备有限公司 | High strength tetrafluoro inside lining pipe joint |
| CN206708600U (en) * | 2017-03-07 | 2017-12-05 | 河南中拓石油工程技术股份有限公司 | A kind of outer fixed ring type HDPE Flange attachment means |
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| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20211224 |
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| RJ01 | Rejection of invention patent application after publication |