CN110439499A - Inhibition soluble type blanking plug and its minimizing technology suitable for speed column end - Google Patents
Inhibition soluble type blanking plug and its minimizing technology suitable for speed column end Download PDFInfo
- Publication number
- CN110439499A CN110439499A CN201910834901.3A CN201910834901A CN110439499A CN 110439499 A CN110439499 A CN 110439499A CN 201910834901 A CN201910834901 A CN 201910834901A CN 110439499 A CN110439499 A CN 110439499A
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- CN
- China
- Prior art keywords
- speed column
- blanking plug
- alloy body
- solvable
- seeker
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- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C23/00—Alloys based on magnesium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C23/00—Alloys based on magnesium
- C22C23/02—Alloys based on magnesium with aluminium as the next major constituent
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C30/00—Alloys containing less than 50% by weight of each constituent
- C22C30/02—Alloys containing less than 50% by weight of each constituent containing copper
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C30/00—Alloys containing less than 50% by weight of each constituent
- C22C30/06—Alloys containing less than 50% by weight of each constituent containing zinc
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F1/00—Etching metallic material by chemical means
- C23F1/10—Etching compositions
- C23F1/14—Aqueous compositions
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- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B23/00—Apparatus for displacing, setting, locking, releasing, or removing tools, packers or the like in the boreholes or wells
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/12—Packers; Plugs
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH DRILLING; MINING
- E21B—EARTH DRILLING, e.g. DEEP DRILLING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR A SLURRY OF MINERALS FROM WELLS
- E21B33/00—Sealing or packing boreholes or wells
- E21B33/10—Sealing or packing boreholes or wells in the borehole
- E21B33/12—Packers; Plugs
- E21B33/1208—Packers; Plugs characterised by the construction of the sealing or packing means
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Geology (AREA)
- Mining & Mineral Resources (AREA)
- Organic Chemistry (AREA)
- Metallurgy (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Fluid Mechanics (AREA)
- Geochemistry & Mineralogy (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Physics & Mathematics (AREA)
- Environmental & Geological Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- General Chemical & Material Sciences (AREA)
- Consolidation Of Soil By Introduction Of Solidifying Substances Into Soil (AREA)
Abstract
A kind of inhibition soluble type blanking plug and its minimizing technology suitable for speed column end, it is characterized by: it includes the low-carbon alloy seeker and solvable alloy body being docking together by mutually matched slot, platform structure, bottom portion of groove in low-carbon alloy seeker butt end is machined with the through-hole extended straight down, and the boss bottom in solvable alloy body butt end is machined with the groove for installing relief valve；The relief valve is inlaid in the groove of solvable alloy body boss portion processing, and bottom is sat above the through-hole for being placed on low-carbon alloy seeker；The solvable alloy body is cylindrical structure, diameter≤speed column internal diameter；The low-carbon alloy seeker is the cylindrical body of the arc-shaped structure in bottom, and diameter is identical as the outer diameter of speed column；It surround the periphery of solvable alloy body, be from top to bottom successively machined with several annular grooves for being embedded with sealing ring, and in the outer ring of low-carbon alloy seeker butt end along the sealing ring being provided with for sealing speed column butt end.
Description
Technical field
The present invention relates to natural gas wells to be suitable for using the technical field more particularly to one kind of speed column water pumping gas production
The inhibition soluble type blanking plug and its minimizing technology of speed column end.
Technical background
Currently, speed column water pumping gas production is the common technology in gas field in the production of natural gas well middle and later periods,
Speed column need to install a blanking plug (Fig. 1) in tubing string end, to prevent underground natural gas from passing through speed column before entering well
Overflow.After under speed column to setting position (1000~3000 meters of underground), need to inject high pressure using dedicated liquid nitrogen pump truck
Liquid nitrogen after going out blanking plug by high-pressure liquid nitrogen, can just get through natural gas acquisition channel, to normally be produced.
Traditional blanking plug is mainly accompanied by sealing ring and constitutes (Fig. 2) by materials such as 35CrMo, 45# as main structure body,
The blanking plug in use, the defects of clamping stagnation and sealing ring are revealed during going into the well there are speed column, is brought to production
Big inconvenience and loss.
It is to be removed using mechanical equipment using physical method in addition, being the minimizing technology of traditional blanking plug, it is specific real
The measure of applying is to prepare high-pressure liquid nitrogen, injection rate tubing string, in high-pressure liquid nitrogen using high-pressure liquid nitrogen pump truck (Fig. 3) on the ground
Under effect (Fig. 4), blanking plug blows (Fig. 5) off from speed column end by high-pressure liquid nitrogen, so far completes the removal work of blanking plug
(Fig. 6).Traditional blanking plug removal, needs to be equipped with a special high-pressure liquid nitrogen car, 3~5 operators, project amount is big, applies
It is long between working hour.High production cost, it is cumbersome and there is a certain security risk, the extremely meaningless consumption of manpower, financial resources.In view of
Status, for the cost of operation company is greatly reduced, mitigates the labor intensity of field personnel, my company is perennial according to scene
The practical experience of production carries out technological innovation in conjunction with live needs of production, has invented a quick, easily removal blocking
The technology of device.
Summary of the invention
The purpose of the present invention is exactly the shortcoming being directed in the presence of the above-mentioned prior art and provides and a kind of be suitable for speed
Spend the inhibition soluble type blanking plug and its minimizing technology of tubing string end.The present invention change material and the structure of traditional blanking plug with
And minimizing technology, keep the sealing function of blanking plug relatively reliable, at the same using chemical method by blanking plug from speed column head
Removal, one can be operated, and be not required to be equipped with engineering vehicles, and project amount is small, and the construction time is short, and production cost is low, operation letter
Singly and without security risk.
The purpose of the present invention can be realized by following technique measures:
Inhibition soluble type blanking plug suitable for speed column end of the invention includes passing through mutually matched slot, platform structure pair
The low-carbon alloy seeker and solvable alloy body being connected together, the bottom portion of groove in low-carbon alloy seeker butt end are machined with perpendicular
The through-hole directly extended downwardly, the boss bottom in solvable alloy body butt end are machined with the groove for installing relief valve；It is described
Relief valve is inlaid in the groove of solvable alloy body boss portion processing, and bottom is sat above the through-hole for being placed on low-carbon alloy seeker；
The solvable alloy body is cylindrical structure, diameter≤speed column internal diameter；The low-carbon alloy seeker is that bottom is in arc
The cylindrical body of shape structure, diameter are identical as the outer diameter of speed column；It surround the periphery of solvable alloy body, from top to bottom successively add
Work has several to be embedded with the annular groove of sealing ring, and is provided on the outer ring of low-carbon alloy seeker butt end edge for sealing speed
Spend the sealing ring of tubing string butt end.
Heretofore described solvable alloy body is prepared by the raw material of following mass percents, in which: aluminium 8%~
40%, copper 3%~30%, magnesium 15%~80%, zinc 5%~25%, lithium 0.1%~8%.
The method and step that the present invention is used to remove inhibition soluble type blanking plug is as follows: the inhibition soluble type blanking plug is pacified
It will be used when speed column and blanking plug arrival production setting position (1000~3000 meters of underground) mounted in speed column end
(or inhibition soluble type blanking plug is mounted on speed column in dissolving the injection at the top of speed column of the lysate of solvable alloy body
Before end, the lysate for dissolving solvable alloy body is pre-loaded into speed column), the solvable alloy body in inhibition soluble type blanking plug
Start to dissolve under the action of lysate, relief valve after solvable alloy body is completely dissolved inside blanking plug is in the conducting shape that floats
State, down-hole high pressure fluid-mixing pass through in relief hole admission velocity tubing string, and pressure in underground and speed column can be made to reach balance,
Then the seeker Automatic-falling of blanking plug, speed column is so far fully on, can be produced；It is described solvable for dissolving
The lytic agent of alloy body is formulated by high concentration chloride and sulphate by molar concentration rate, wherein Cu2+Molar concentration
For 20~27%, Ag+Molar concentration is 3~5%, CL~Molar concentration is 20~24%, Na+Molar concentration is 8~10%, K+It is mole dense
Degree is 10~12%, SO4 2~Molar concentration be 26~30%, by adjusting various ions concentration, it can be achieved that adjusting solvable alloy body
Solution rate, be able to effective control to dissolution time.
The present invention be suitable for bore be 25.40mm(1.0 "), 31.75mm(1.25 "), 38.1 mm(1. 5 "), 44.45
Mm(1. 75 "), 50.8 mm(2.0 ") equal-specification speed column.
The present invention can be by adjusting the component ratio of solvable alloy body, the ingredient of lysate and concentration, adjustment blanking plug knot
The data such as structure size, controllable speed tubing string turn-on time (6~120 hours), effectively meet different clients and lead to speed column
The different of logical time require.
Beneficial effects of the present invention are as follows:
1, inhibition soluble type blanking plug of the invention uses pressure-relief valve structure, can within the set time, in the work of external pressure
It is voluntarily connected under, realizes pressure self-balancing, promote the seeker Automatic-falling of blanking plug；
2, inhibition soluble type blanking plug and its minimizing technology of the present invention are to be carried out using the method for chemistry, are not needed special-purpose vehicle
With professional construction personnel, low temperature, operation with high pressure security risk is not present, greatly reduces production cost, improves production efficiency,
Lysate and dissolved compound are nontoxic, will not environment and equipment, personnel be polluted and be endangered.
Detailed description of the invention
Fig. 1 is the scheme of installation of prior art blanking plug.
Fig. 2 is the structure chart of prior art blanking plug.
Fig. 3 is prior art blanking plug removal Ground Operation schematic diagram.
Fig. 4 is injection high-pressure liquid nitrogen stage schematic diagram.
Fig. 5 is blanking plug by high-pressure liquid nitrogen blow-off phase schematic diagram.
Fig. 6 is that blanking plug is completely removed stage schematic diagram.
Fig. 7 is the structure chart of blanking plug of the present invention.
Fig. 8 is lysate prepackage and blanking plug erection stage schematic diagram of the invention.
Fig. 9 is that solvable alloy body of the invention is in dissolution phase schematic diagram.
Figure 10 is relief valve of the invention in floating on state stage schematic diagram.
Figure 11 is seeker Automatic-falling stage schematic diagram of the invention.
Figure 12 is that blanking plug of the invention is completely removed stage schematic diagram.
Serial number in figure: 1 is high-pressure liquid nitrogen pump truck, and 2 be well head christmas tree, and 3 be operator, and 4 be gas-bearing formation, and 5 be set
Pipe, 6 be speed column, and 7 be down-hole high pressure fluid-mixing, and 8 be blanking plug, and 9 be sealing ring, and 10 be high-pressure liquid nitrogen, and 11 be solvable
Alloy body, 12 be sealing ring, and 13 be relief valve, and 14 be seeker, and 15 be dedicated lysate.
Figure 13 is the raw material proportioning subordinate list of solvable alloy body.
Figure 14,15 are raw material proportioning subordinate lists for dissolving the lytic agent of solvable alloy body.
Specific embodiment
The present invention is further described below with reference to embodiment (attached drawing):
As shown in fig. 7, the inhibition soluble type blanking plug suitable for speed column end of the invention includes by mutually matched
The low-carbon alloy seeker 14 and solvable alloy body 11 that slot, platform structure are docking together, in low-carbon alloy seeker butt end
Bottom portion of groove is machined with the through-hole extended straight down, and the boss bottom in solvable alloy body butt end is machined with to be let out for installing
The groove of pressure valve；The relief valve 13 is inlaid in the groove of solvable alloy body boss portion processing, and bottom is sat and is placed on low-carbon alloy
Above the through-hole of seeker；The solvable alloy body is cylindrical structure, the internal diameter of diameter≤speed column 6；The low-carbon closes
Golden seeker is the cylindrical body of the arc-shaped structure in bottom, and diameter is identical as the outer diameter of speed column；Around the outer of solvable alloy body
Disc is from top to bottom successively machined with several annular grooves for being embedded with sealing ring 9, and in the outer of low-carbon alloy seeker butt end
Ring is along the sealing ring 12 being provided with for sealing speed column butt end.
Heretofore described solvable alloy body is prepared by the raw material of following mass percents, in which: aluminium 8%~
40%, copper 3%~30%, magnesium 15%~80%, zinc 5%~25%, lithium 0.1%~8%.(being detailed in Figure 13)
The method and step that the present invention is used to remove inhibition soluble type blanking plug is as follows: the inhibition soluble type blanking plug is mounted on
Speed column end (Fig. 8) will be used when speed column and blanking plug arrival production setting position (1000~3000 meters of underground)
(or inhibition soluble type blanking plug is mounted on speed column in dissolving the injection at the top of speed column of the lysate of solvable alloy body
Before end, the lysate for dissolving solvable alloy body is pre-loaded into speed column), the solvable alloy body in inhibition soluble type blanking plug
Start to dissolve (Fig. 9) under the action of lysate, relief valve after solvable alloy body is completely dissolved inside blanking plug is in floating
On state (Figure 10), down-hole high pressure fluid-mixing is by that can make in underground and speed column in relief hole admission velocity tubing string
Pressure reaches balance, and then the seeker Automatic-falling (Figure 11) of blanking plug, speed column are so far fully on (Figure 12)
It is produced；The lytic agent for dissolving solvable alloy body is by high concentration chloride and sulphate by molar concentration rate
It is formulated, wherein Cu2+Molar concentration is 20~27%, Ag+Molar concentration is 3~5%, CL~Molar concentration is 20~24%, Na+
Molar concentration is 8~10%, K+Molar concentration is 10~12%, SO4 2~Molar concentration is 26~30%, by adjusting various ions
Concentration is able to effective control (being detailed in Figure 14,15) to dissolution time, it can be achieved that adjust the solution rate of solvable alloy body.
The present invention be suitable for bore be 25.40mm(1.0 "), 31.75mm(1.25 "), 38.1 mm(1. 5 "), 44.45
Mm(1. 75 "), 50.8 mm(2.0 ") equal-specification speed column.
The present invention can be by adjusting the component ratio of solvable alloy body, the ingredient of lysate and concentration, adjustment blanking plug knot
The data such as structure size, controllable speed tubing string turn-on time (6~120 hours), effectively meet different clients and lead to speed column
The different of logical time require.
Claims (3)
1. a kind of inhibition soluble type blanking plug suitable for speed column end, it is characterised in that: it includes passing through mutual cooperation
Slot, platform structure the low-carbon alloy seeker and solvable alloy body that are docking together, in the recessed of low-carbon alloy seeker butt end
Trench bottom is machined with the through-hole extended straight down, and the boss bottom in solvable alloy body butt end is machined with for installing pressure release
The groove of valve；The relief valve is inlaid in the groove of solvable alloy body boss portion processing, and bottom, which is sat, is placed on low-carbon alloy guidance
Above the through-hole of head；The solvable alloy body is cylindrical structure, diameter≤speed column internal diameter；The low-carbon alloy guidance
Head is the cylindrical body of the arc-shaped structure in bottom, and diameter is identical as the outer diameter of speed column；Around solvable alloy body periphery, by
Several annular grooves for being embedded with sealing ring are successively machined under, and in the outer ring of low-carbon alloy seeker butt end along setting
There is the sealing ring for sealing speed column butt end.
2. the inhibition soluble type blanking plug according to claim 1 suitable for speed column end, it is characterised in that: described
Solvable alloy body is prepared by the raw material of following mass percents, in which: aluminium 8%~40%, copper 3%~30%, magnesium 15%~
80%, zinc 5%~25%, lithium 0.1%~8%.
3. a kind of method for removing inhibition soluble type blanking plug described in claim 1, it is characterised in that: the method step
It is as follows: the inhibition soluble type blanking plug to be mounted on speed column end, when speed column and blanking plug reach production setting
When position, will be used to dissolve the lysate of solvable alloy body and be injected at the top of speed column, in inhibition soluble type blanking plug can
Molten alloy body starts to dissolve under the action of lysate, and relief valve after solvable alloy body is completely dissolved inside blanking plug is in floating
Dynamic on state, down-hole high pressure fluid-mixing is by that can make pressure in underground and speed column in relief hole admission velocity tubing string
Reach balance, then the seeker Automatic-falling of blanking plug, speed column is so far fully on, can be produced；The use
It is formulated by high concentration chloride and sulphate by molar concentration rate in the lytic agent for dissolving solvable alloy body, wherein
Cu2+Molar concentration is 20~27%, Ag+Molar concentration is 3~5%, CL~Molar concentration is 20~24%, Na+Molar concentration be 8~
10%, K+Molar concentration is 10~12%, SO4 2~Molar concentration be 26~30%, by adjusting various ions concentration, it can be achieved that adjust
The solution rate for saving solvable alloy body is able to effective control to dissolution time.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910834901.3A CN110439499A (en) | 2019-09-05 | 2019-09-05 | Inhibition soluble type blanking plug and its minimizing technology suitable for speed column end |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910834901.3A CN110439499A (en) | 2019-09-05 | 2019-09-05 | Inhibition soluble type blanking plug and its minimizing technology suitable for speed column end |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN110439499A true CN110439499A (en) | 2019-11-12 |
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ID=68439145
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910834901.3A Pending CN110439499A (en) | 2019-09-05 | 2019-09-05 | Inhibition soluble type blanking plug and its minimizing technology suitable for speed column end |
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| CN (1) | CN110439499A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110905437A (en) * | 2019-12-16 | 2020-03-24 | 中国石油天然气股份有限公司西南油气田分公司工程技术研究院 | Soluble plug |
| CN110952949A (en) * | 2019-11-22 | 2020-04-03 | 中国石油天然气股份有限公司 | Soluble plugging tool for tail end of velocity string and using method thereof |
| CN113025857A (en) * | 2021-02-10 | 2021-06-25 | 北京科技大学 | Soluble magnesium alloy material for all-metal bridge plug rubber cylinder and preparation method thereof |
-
2019
- 2019-09-05 CN CN201910834901.3A patent/CN110439499A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110952949A (en) * | 2019-11-22 | 2020-04-03 | 中国石油天然气股份有限公司 | Soluble plugging tool for tail end of velocity string and using method thereof |
| CN110905437A (en) * | 2019-12-16 | 2020-03-24 | 中国石油天然气股份有限公司西南油气田分公司工程技术研究院 | Soluble plug |
| CN113025857A (en) * | 2021-02-10 | 2021-06-25 | 北京科技大学 | Soluble magnesium alloy material for all-metal bridge plug rubber cylinder and preparation method thereof |
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