CN116446831A - Water injection well layered measuring and adjusting device and method using pressure wave as carrier - Google Patents
Water injection well layered measuring and adjusting device and method using pressure wave as carrier Download PDFInfo
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- CN116446831A CN116446831A CN202210014210.0A CN202210014210A CN116446831A CN 116446831 A CN116446831 A CN 116446831A CN 202210014210 A CN202210014210 A CN 202210014210A CN 116446831 A CN116446831 A CN 116446831A
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- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 title claims abstract description 131
- 238000002347 injection Methods 0.000 title claims abstract description 81
- 239000007924 injection Substances 0.000 title claims abstract description 81
- 238000000034 method Methods 0.000 title claims abstract description 17
- 230000001105 regulatory effect Effects 0.000 claims abstract description 22
- 238000005259 measurement Methods 0.000 claims abstract description 20
- 239000000969 carrier Substances 0.000 claims abstract description 7
- 230000005540 biological transmission Effects 0.000 claims abstract description 6
- 238000004891 communication Methods 0.000 claims description 10
- 238000012545 processing Methods 0.000 claims description 3
- 238000002360 preparation method Methods 0.000 claims description 2
- 238000000605 extraction Methods 0.000 abstract description 2
- 238000009826 distribution Methods 0.000 description 3
- 238000006467 substitution reaction Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 1
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Abstract
The invention belongs to the technical field of oilfield oil extraction engineering, and particularly relates to a water injection well layered measuring and regulating device and method taking pressure waves as carriers. The invention mainly solves the problems of slow underground ground information transmission, short service life of a battery of a pressure wave generating device, high cost of a built-in flowmeter of an intelligent water distributor and the like in the existing pressure pulse type intelligent measuring and adjusting system. The system comprises a ground measurement and control system (1), a wellhead constant pressure system (2) and an intelligent separated layer water injection pipe column (3); the invention realizes layered water injection measurement and adjustment by using a ground measurement and control system (1), a wellhead constant pressure system (2) and an intelligent layered water injection pipe column (3) and measuring the opening of a flow control valve of each layer of underground intelligent water distributors (31) meeting the injection allocation requirement under the same wellhead injection pressure. The invention has the advantages of no need of frequently transmitting information to the ground underground, prolonging the service life of the intelligent water injection well, no need of a built-in flowmeter of the intelligent water distributor, and the like.
Description
Technical Field
The invention belongs to the technical field of oilfield oil extraction engineering, and particularly relates to a water injection well layered measuring and regulating device and method taking pressure waves as carriers.
Background
The water injection well layered measuring and regulating method using pressure wave as carrier is one of the layered water distribution methods commonly used in water injection well in oil field at present. The intelligent water distributor comprises a flowmeter, a flow control valve, a pressure gauge and the like, and is prepared layer by layer in a ground control mode, so that the aim of layered water distribution is fulfilled. However, this method has two disadvantages: firstly, the flowmeter in the water distributor has complex structure and higher manufacturing cost, so that the whole process cost is higher; secondly, the information is transmitted to the ground underground, the flow control valve of the intelligent water distributor is repeatedly opened and closed to form an ordered pressure code, the information transmission efficiency is low, the battery power consumption is high, and the service life of the whole intelligent water injection well is shortened.
Disclosure of Invention
The invention aims to provide a water injection well layered measuring and regulating device and method taking pressure waves as carriers, which simplify the internal structure of an intelligent water distributor, do not need the working mode of frequently transmitting information to the ground underground, reduce the overall process cost and effectively prolong the service life of the intelligent water injection well.
The invention mainly comprises a ground measurement and control system, a wellhead constant pressure system and an intelligent layered water injection pipe column.
The ground measurement and control system is used for sending control instructions to the underground and receiving underground measurement data;
the wellhead constant pressure system is used for keeping wellhead injection pressure stable when a flow control valve of the underground intelligent water distributor acts;
the intelligent layered water injection pipe column is used for separating water injection layer sections and realizing measurement and control of layered water injection quantity;
the intelligent separated layer water injection pipe column comprises a cable passing packer, an intelligent water distributor and an oil pipe; the cable packer and the intelligent water distributor form a unit body, and the unit body is connected through an oil pipe and is lowered into the designed depth corresponding to the water injection layer section.
The ground measurement and control system comprises a ground computer, a wireless communication device and a ground control box; the ground computer and the ground control box realize data transmission through the wireless communication device.
The wellhead constant pressure system comprises a water injection valve, a pressure gauge, a pressure regulating valve and a flowmeter; the pressure gauge is in threaded connection with the water injection pipeline, and the pressure regulating valve and the flowmeter are connected with the flange of the water injection pipeline; the pressure regulating valve has an automatic constant pressure mode.
The intelligent water distributor comprises a battery pack, a flow control valve, a wireless receiving unit, a control circuit and a pressure gauge; the signal sent by the ground computer is transmitted to a ground control box through a wireless communication device, the ground control box processes the signal and then controls a wellhead pressure regulating valve to act, the pressure in an oil pipe is converted into a pressure pulse signal code according to time change, and the pressure pulse signal code is transmitted into all intelligent water distributors in the well; after the wireless receiving unit in the intelligent water distributor receives the pressure pulse signal code, the flow control valve of the intelligent water distributor is controlled to act, so that the opening degree of the flow control valve of the intelligent water distributor is adjusted.
A layered measuring and adjusting method of a layered measuring and adjusting device of a water injection well by using pressure waves as carriers comprises the following steps:
a. starting an automatic constant pressure mode of a wellhead constant pressure system, and performing constant pressure treatment on incoming water through a wellhead pressure regulating valve to keep the incoming water at a certain pressure value P within an allowable injection pressure range Pouring ；
b. Sending a control command to the underground through a ground computer, and closing flow control valves of all intelligent water distributors except the first layer;
c. sending a control command to the underground through a ground computer, opening a flow control valve of the first-layer intelligent water distributor, wherein the flow value measured by the wellhead flowmeter at the moment is the injection quantity of the first-layer intelligent water distributor, stopping the flow control valve of the first-layer intelligent water distributor when the injection allocation requirement of the first-layer is met, and recording the opening of the flow control valve of the first-layer intelligent water distributor at the moment;
d. sending an instruction to the underground through a ground computer, opening a flow control valve of an intelligent water distributor to be measured and regulated to a fully-opened state, and then closing the flow control valve of a first layer of intelligent water distributors to a fully-closed state;
e. processing the rest intelligent water distributors in the same steps as steps b-d in sequence to measure the injection pressure P of the flow control valve of each intelligent water distributor Pouring Opening meeting the injection allocation requirement is arranged downwards;
f. the preparation scheme is obtained by the steps, namely the injection pressure is kept at the pressure value P Pouring The flow control valve of each layer of intelligent water distributor in the well keeps the opening degree measured in the step; at this time, the injection amounts of the layers satisfy the injection allocation requirement.
Compared with the prior art, the invention has the following advantages:
the intelligent water distributor has the advantages of simplified structure, low cost and contribution to popularization; the underground information is not required to be frequently transmitted to the ground, so that the problem of slow underground information transmission to the ground is avoided, and the measuring and adjusting efficiency is improved; the flow control valve of the intelligent water distributor is not required to repeatedly switch to form a pressure pulse code, so that the service life of the battery is prolonged.
Description of the drawings: FIG. 1 is a schematic diagram of the overall structure of the present invention; fig. 2 is a schematic structural view of an intelligent water distributor 31 according to the present invention.
In the accompanying drawings: the system comprises a 1-ground measurement and control system, a 2-wellhead constant pressure system, a 3-intelligent separated layer water injection pipe column, a 10-ground computer, a 11-wireless communication device, a 12-ground control box, a 20-water injection valve, a 21-pressure gauge, a 22-pressure regulating valve, a 23-flowmeter, a 30-cable-passing packer, a 31-intelligent water distributor, a 32-oil pipe, a 310-battery pack, a 311-flow control valve, a 312-wireless receiving unit, a 313-control circuit and a 314-pressure gauge.
The specific embodiment is as follows: the invention is further described with reference to the accompanying drawings: the advantages and features of the present invention will become more apparent as the description proceeds, as illustrated in fig. 1 and 2. These examples are merely exemplary and do not limit the scope of the invention in any way. It will be understood by those skilled in the art that various changes and substitutions of details and forms of the technical solution of the present invention may be made without departing from the spirit and scope of the present invention, but these changes and substitutions fall within the scope of the present invention.
The invention mainly comprises a ground measurement and control system 1, a wellhead constant pressure system 2 and an intelligent separated layer water injection pipe column 3.
The ground measurement and control system 1 is used for sending control instructions to the underground and receiving underground measurement data;
the wellhead constant pressure system 2 is used for keeping wellhead injection pressure stable when the flow control valve 311 of the underground intelligent water distributor 31 acts;
the intelligent separate-layer water injection pipe column 3 is used for separating water injection intervals and realizing measurement and control of separate-layer water injection quantity;
the intelligent separated layer water injection string 3 comprises a cable packer 30, an intelligent water distributor 31 and an oil pipe 32; the cable packer 30 and the intelligent water distributor 31 form a unit body, and the unit body is connected through an oil pipe 32 and is lowered into the designed depth corresponding to the water injection layer section.
The ground measurement and control system 1 mainly comprises a ground computer 10, a wireless communication device 11 and a ground control box 12; wherein the ground computer 10 and the ground control box 12 realize data transmission through the wireless communication device 11.
The wellhead constant pressure system 2 mainly comprises a water injection valve 20, a pressure gauge 21, a pressure regulating valve 22 and a flowmeter 23; the pressure gauge 21 is in threaded connection with a water injection pipeline, and the pressure regulating valve 22 and the flowmeter 23 are in flange connection with the water injection pipeline; the pressure regulating valve 22 has an automatic constant pressure mode.
The intelligent water distributor 31 comprises a battery pack 310, a flow control valve 311, a wireless receiving unit 312, a control circuit 313 and a pressure gauge 314; the working mode is that the signal sent by the ground computer 10 is transmitted to the ground control box 12 through the wireless communication device 11, the ground control box 12 processes the signal and then controls the wellhead pressure regulating valve 23 to act, the pressure in the oil pipe is converted into a pressure pulse signal code according to time change, and the pressure pulse signal code is transmitted into each underground intelligent water distributor 31; after receiving the pressure pulse signal code, the wireless receiving unit 312 in the intelligent water distributor controls the flow control valve 311 of the intelligent water distributor 31 to act, so as to realize the adjustment of the opening of the flow control valve 311 of the intelligent water distributor 31.
Taking a water injection well with two layers of water to be distributed in a layered way as an example, the measuring and adjusting method of the invention is further described in detail: assuming that the design scheme has 2 water injection layers with the water injection amounts of
Q 1 is matched with =30m 3 /d，Q 2 match with =40 m 3 And/d, the injection allocation precision is 10%.
The measurement and adjustment are carried out according to the following steps:
a. the automatic constant pressure mode of the wellhead constant pressure system 2 is started, the constant pressure treatment is carried out on the incoming water through the wellhead pressure regulating valve 22, and the incoming water is kept at a certain pressure value P within the allowable injection pressure range according to geological requirements Pouring In P Pouring Take 12.0MPa as an example;
b. sending a control command to the underground through a ground computer, and closing flow control valves of all intelligent water distributors except the first layer;
c. the control command is sent to the underground through the surface computer 10, the flow control valve 311 of the first layer intelligent water distributor 31 is opened, and the flow value measured by the wellhead flowmeter 32 is 29 m 3 The injection quantity of the first layer intelligent water distributor 31 is 29 m 3 And/d, meeting the injection allocation requirements, the flow of the first layer intelligent water distributor 31The flow control valve 311 stops operating, and the opening of the flow control valve 311 of the first intelligent water distributor 31 is recorded as 50%;
d. opening the flow control valve 311 of the second intelligent water distributor 31 to a fully opened state, and then closing the flow control valve 311 of the first intelligent water distributor 31 to a fully closed state;
e. the incoming water is subjected to constant pressure treatment through a wellhead constant pressure system 2, and P is kept Pouring =12.0MPa；
At this time, the flow rate measured by the wellhead flow meter 23 is 50 m 3 The injection quantity of the second-layer intelligent water distributor 31 is 50 m 3 And/d, if the injection allocation requirement is not met, closing the flow control valve 311 of the second-layer intelligent water distributor 31, and when the flow value measured by the wellhead flowmeter 23 is 40 m 3 When/d, the flow control valve 311 of the second-layer intelligent water distributor 31 stops operating, and the opening degree of the flow control valve 311 of the second-layer intelligent water distributor 31 is recorded to be 35%;
f. the incoming water is subjected to constant pressure treatment through a wellhead constant pressure system 2, so that the injection pressure is kept at P Pouring =12.0 MPa; the opening degree of the flow control valve 311 of the first layer intelligent water distributor 31 is 50%, and the opening degree of the flow control valve 311 of the second layer intelligent water distributor 31 is 35%; at this time, the injection amounts of the layers satisfy the injection allocation requirement.
The same steps are adopted for more than two layers of stratum needing layered water distribution.
Claims (5)
1. The utility model provides an use water injection well layering survey device of pressure wave as carrier which characterized in that: the system comprises a ground measurement and control system (1), a wellhead constant pressure system (2) and an intelligent separated layer water injection pipe column (3);
the ground measurement and control system (1) is used for sending control instructions to the underground and receiving underground measurement data;
the wellhead constant pressure system (2) is used for keeping wellhead injection pressure stable when a flow control valve (311) of the underground intelligent water distributor (31) acts;
the intelligent separated layer water injection pipe column (3) is used for separating water injection intervals and realizing measurement and control of separated layer water injection quantity;
the intelligent separated layer water injection pipe column (3) comprises a cable packer (30), an intelligent water distributor (31) and an oil pipe (32); the cable packer (30) and the intelligent water distributor (31) form a unit body, and the unit body is connected through an oil pipe (32) and is lowered into the designed depth corresponding to the water injection interval.
2. The water injection well layered measuring and adjusting device using pressure waves as carriers as claimed in claim 1, wherein the device comprises the following components: the ground measurement and control system (1) comprises a ground computer (10), a wireless communication device (11) and a ground control box (12); wherein the ground computer (10) and the ground control box (12) realize data transmission through the wireless communication device (11).
3. The water injection well layered measuring and adjusting device using pressure waves as carriers as claimed in claim 1, wherein the device comprises the following components: the wellhead constant pressure system (2) comprises a water injection valve (20), a pressure gauge (21), a pressure regulating valve (22) and a flowmeter (23); the pressure gauge (21) is in threaded connection with the water injection pipeline, and the pressure regulating valve (22) and the flowmeter (23) are in flange connection with the water injection pipeline; the pressure regulating valve (22) has an automatic constant pressure mode.
4. The water injection well layered measuring and adjusting device using pressure waves as carriers as claimed in claim 1, wherein the device comprises the following components: the intelligent water distributor (31) comprises a battery pack (310), a flow control valve (311), a wireless receiving unit (312), a control circuit (313) and a pressure gauge (314); the signal sent by the ground computer (10) is transmitted to the ground control box (12) through the wireless communication device (11), the ground control box (12) controls the wellhead pressure regulating valve (23) to act after processing the signal, and the pressure in the oil pipe is converted into a pressure pulse signal code according to time change and is transmitted to all the underground intelligent water distributors (31); after the wireless receiving unit (312) in the intelligent water distributor (31) receives the pressure pulse signal code, the flow control valve (311) of the intelligent water distributor (31) is controlled to act, and the opening degree of the flow control valve (311) of the intelligent water distributor (31) is adjusted.
5. A method for measuring and adjusting a water injection well layer by using the pressure wave as a carrier according to claim 1, which is characterized in that: the method comprises the following steps:
a. opening an automatic constant pressure mode of a wellhead constant pressure system (2), and performing constant pressure treatment on incoming water through a wellhead pressure regulating valve (22) to keep the incoming water at a certain pressure value P within an allowable injection pressure range Pouring ；
b. Sending a control command to the underground through the surface computer (10), and closing flow control valves (311) of all intelligent water distributors (31) except the first layer;
c. the method comprises the steps that a ground computer (10) sends a control command to the underground, a flow control valve (311) of an intelligent water distributor (31) of a first layer is opened, at the moment, the flow value measured by a wellhead flowmeter (23) is the injection quantity of the intelligent water distributor (31) of the first layer, when the injection requirement of the first layer is met, the flow control valve (311) of the intelligent water distributor (31) of the first layer stops acting, and the opening degree of the flow control valve (311) of the intelligent water distributor (31) of the first layer at the moment is recorded;
d. sending an instruction to the underground through a ground computer (10), opening a flow control valve (311) of an intelligent water distributor (31) to be measured and regulated to a fully-opened state, and then closing the flow control valve (311) of a first layer of intelligent water distributors (31) to a fully-closed state;
e. processing the rest intelligent water distributors (31) in the same way as in the steps b-d in sequence, and measuring the injection pressure P of the flow control valve (311) of each intelligent water distributor (31) Pouring Opening meeting the injection allocation requirement is arranged downwards;
f. the preparation scheme is obtained through the steps: the injection pressure is maintained at the pressure value P Pouring The flow control valve (311) of each layer of intelligent water distributor (31) in the well keeps the opening degree measured in the step; at this time, the injection amounts of the layers satisfy the injection allocation requirement.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN202210014210.0A CN116446831A (en) | 2022-01-06 | 2022-01-06 | Water injection well layered measuring and adjusting device and method using pressure wave as carrier |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210014210.0A CN116446831A (en) | 2022-01-06 | 2022-01-06 | Water injection well layered measuring and adjusting device and method using pressure wave as carrier |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116752935A (en) * | 2023-08-23 | 2023-09-15 | 西安洛科电子科技股份有限公司 | Ground control device for high-speed pulse communication and regulation and control method thereof |
| CN117449814A (en) * | 2023-11-15 | 2024-01-26 | 中国石油工程建设有限公司 | Pressure-controlled cable-free intelligent layered water injection system and method |
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| CN106150460A (en) * | 2016-08-25 | 2016-11-23 | 中国石油天然气股份有限公司 | Water injection well layered measurement and adjustment process device and measurement and adjustment method thereof |
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2022
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| RU2488687C1 (en) * | 2012-02-13 | 2013-07-27 | Открытое акционерное общество "Татнефть" имени В.Д. Шашина | Method of simultaneous and separate operation of injection well |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN116752935A (en) * | 2023-08-23 | 2023-09-15 | 西安洛科电子科技股份有限公司 | Ground control device for high-speed pulse communication and regulation and control method thereof |
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| CN117449814A (en) * | 2023-11-15 | 2024-01-26 | 中国石油工程建设有限公司 | Pressure-controlled cable-free intelligent layered water injection system and method |
| CN117449814B (en) * | 2023-11-15 | 2024-08-23 | 中国石油工程建设有限公司 | Pressure-controlled cable-free intelligent layered water injection system and method |
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