CN212671707U - Underground switch device for controlling pressure in shaft - Google Patents
Underground switch device for controlling pressure in shaft Download PDFInfo
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- CN212671707U CN212671707U CN202020706261.6U CN202020706261U CN212671707U CN 212671707 U CN212671707 U CN 212671707U CN 202020706261 U CN202020706261 U CN 202020706261U CN 212671707 U CN212671707 U CN 212671707U
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- 239000003129 oil well Substances 0.000 abstract description 12
- 238000006243 chemical reaction Methods 0.000 abstract description 4
- 238000011084 recovery Methods 0.000 abstract description 2
- 239000003921 oil Substances 0.000 description 99
- 238000005086 pumping Methods 0.000 description 40
- 238000004519 manufacturing process Methods 0.000 description 26
- 238000001514 detection method Methods 0.000 description 11
- 238000000605 extraction Methods 0.000 description 7
- 230000009471 action Effects 0.000 description 5
- 238000000034 method Methods 0.000 description 5
- 238000003825 pressing Methods 0.000 description 4
- 230000008878 coupling Effects 0.000 description 3
- 238000010168 coupling process Methods 0.000 description 3
- 238000005859 coupling reaction Methods 0.000 description 3
- 230000004048 modification Effects 0.000 description 3
- 238000012986 modification Methods 0.000 description 3
- 230000000694 effects Effects 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000010276 construction Methods 0.000 description 1
- 239000010779 crude oil Substances 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000035699 permeability Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 230000000630 rising effect Effects 0.000 description 1
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Abstract
The utility model belongs to the technical field of oil recovery engineering, concretely relates to downhole switching device of control pit shaft internal pressure. The utility model is formed by organically combining a switch control piece connected below an oil pipe under a pump and a switch main body which is seated in a sleeve; the switch control member is controlled to be turned on by being in contact with the switch main body. The utility model discloses can the effective control pit shaft internal pressure, with pit shaft high pressure conversion ordinary pressure or low pressure, realize that the oil well has the quick operation of pole system and no pole system, effectively reduced the risk of operation.
Description
Technical Field
The utility model belongs to the technical field of oil recovery engineering, concretely relates to downhole switching device of control pit shaft internal pressure.
Background
The ultra-low permeability compact oil is an important resource replacement layer in recent years, the pressure of the ground layer after the volume fracturing of the compact oil is high, the initial discharge capacity is large, the gas content of produced liquid is high, and the dangerous case of well kick and overflow can occur at any time in the operation process. In addition, the well killing mode is not suitable for taking reservoir protection factors such as oil layer pollution and the like into consideration when the well killing device is used for tripping operation.
The existing oil pumping well has a rod pump operation: generally, a combined device of a single-gate manual blowout preventer, a standard oil extraction well head, an oil pipe plug valve and a sucker rod blowout preventer is arranged on a well head to realize operation under pressure and complete wellbore control; the cable needs to be cut off rapidly during the operation of the rodless pump pipe cable, the blowout preventer is used for realizing well shut-in, and certain risk exists for the high-pressure well, namely the blowout preventer cannot be installed in a rush mode, so that the high-pressure well is out of control, and well blowout and well kick occur to cause well control events.
SUMMERY OF THE UTILITY MODEL
The utility model provides a controlling shaft internal pressure's downhole switch device, aim at provide one kind can control shaft internal pressure, with shaft high pressure conversion ordinary pressure or low pressure, realize that the oil well has pole system, no pole system to put into production fast, reduces the downhole switch device of operation risk.
In order to achieve the above object, the utility model adopts the following technical scheme:
a downhole switch device for controlling pressure in a wellbore comprises a switch control element connected below a pump oil pipe and a switch main body sealed in a casing; the switch control member is controlled to be turned on by being in contact with the switch main body.
The switch main body comprises a releasing packer, a support element and a float switch; the float switch, the releasing packer and the supporting piece are sequentially connected from top to bottom.
The supporting part adopts a supporting slip.
The switch control piece is a through rod of a hollow conical body.
The through rod is a hollow integrated structure which is composed of a cylinder at the upper part and a cone at the lower part.
Has the advantages that:
the utility model is formed by organically combining a switch control piece connected below an oil pipe under a pump and a switch main body which is seated in a sleeve; the switch control member is controlled to be turned on by being in contact with the switch main body. The utility model discloses can the effective control pit shaft internal pressure, with pit shaft high pressure conversion ordinary pressure or low pressure, realize that the oil well has the quick operation of pole system and no pole system, effectively reduced the risk of operation.
The above description is only an overview of the technical solution of the present invention, and in order to clearly understand the technical means of the present invention and to implement the technical solution according to the content of the description, the following detailed description is made with reference to the preferred embodiments of the present invention and accompanying drawings.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic view of the present invention applied to a rod lifting system;
FIG. 2 is a schematic view of the present invention applied to a rodless lifting system;
fig. 3 is a state diagram of the present invention controlling the pressure in the wellbore.
In the figure: 1-pumping down the oil pipe; 2-releasing the packer; 3-supporting slips; 4-a float switch; 5-through rod; 6-plugging; 7-floral tube; 8-tail pipe; 9-a working machine; 10-operating an oil pipe; 11-continuous cable laying oil pipe; 12-an electrical submersible pump; 13-production well head; 14-oil well pump; 15-sucker rod; 16-a pumping unit; 17-a sleeve; 18-an oil extraction pipe; 19-a control cabinet; 20-cable.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
The first embodiment is as follows:
a downhole switching device for controlling pressure in a wellbore according to fig. 1-3, comprising a switch control connected below a pump down tube 1 and a switch body set in a casing 17; the switch control member is controlled to be turned on by being in contact with the switch main body.
In actual use, the well-connected main body of the switch is connected to the lower end of an operating oil pipe 10, then the switch is conveyed into a sleeve 17 through an operating machine 9, after the switch is lowered to a preset position, the operating oil pipe 10 is lifted up, a supporting slip 3 is opened, a wellhead is pressed to set a releasing packer 2, and after the releasing packer is set, a load is lifted up and releasing is completed; when the pressure in the shaft exceeds a preset value, selecting an oil extraction system according to the requirement of pump lowering operation; when a rodless oil production system is needed, the switch control piece is connected below the pump lower oil pipe 1, then the switch control piece, the pump lower oil pipe 1 and the electric submersible pump 12 are sequentially put into a well through the continuous cable laying oil pipe 11, the speed is reduced when the switch main body is away from a preset position, the switch main body is lifted by 1.8-2.2 m after bottom detection, the electric cable 20 is quickly connected, then the pipe column is continuously put down for the bottom detection distance, the switch control piece is in contact with the switch main body and the switch main body is opened, a production wellhead 13 is quickly installed, and well completion production is carried out; when a rod oil extraction system is needed, the switch control piece is connected below the pump lower oil pipe 1, the switch control piece, the pump lower oil pipe 1 and the oil pump 14 are sequentially put into the well through the oil pipe pump 18, the speed is reduced when the switch control piece leaves a preset position of the switch main body, the switch control piece is lifted by about 0.8-1.2m after bottom detection, and the switch main body is ensured to be temporarily closed; hanging an oil pumping pipe 18 at the well mouth, continuing to put a sucker rod 15, colliding the pump when the sucker rod 15 reaches the position of the oil well pump 14, adjusting the position of the sucker rod 15 and hanging the sucker rod 15 in the well; and (3) lowering the oil pumping pipe 18 again, when the oil pumping pipe 18 exceeds the bottom detection distance, enabling the switch control part to be in contact with the switch main body and opening the switch main body under the action of the suspended weight of the oil pumping pipe 18, quickly installing a well head, connecting the oil pumping rod 15, adjusting the anti-impact distance, and starting the oil pumping unit 16 for production. When the well repairing or pump detecting operation is carried out again, the continuous cable laying oil pipe 11 or the oil pumping pipe 18 is directly lifted out, the float switch 4 is closed, and then the well repairing or pump detecting operation is carried out. When the well is repaired again or the pump is checked, the continuous cable laying oil pipe 11 or the oil pumping pipe 18 is directly lifted out, the main body of the switch is closed, the main body of the switch seals the inner space of the oil pumping pipe 18 at the moment, the packer 2 seals the annular space of an oil sleeve, and the operation without pressure can be realized at the position above the shaft switch, so that the production safety is ensured.
The utility model discloses an oil pipe under the pump and connect under the pump oil pipe below switch control and control the organic setting of the switch ware main part opened by switch control, effectively controlled pit shaft internal pressure, with pit shaft high pressure conversion ordinary pressure or low pressure, reduced the operation risk, ensured the construction of safety ring guarantor. The utility model discloses convenient operation has shortened the time that volume fracturing back oil well waited for the time of putting into production greatly, has improved production efficiency.
Example two:
a downhole switching device for controlling pressure in a wellbore according to the embodiments of fig. 1-3, differs from the first embodiment in that: the switch main body comprises a releasing packer 2, a support element and a float switch 4; the float switch 4, the releasing packer 2 and the support piece are sequentially connected from top to bottom.
When in actual use, the plug 6, the floral tube 7, the tail tube 8, the supporting slip 3, the releasing packer 2 and the float switch 4 are sequentially connected from bottom to top and then connected below the operating oil pipe 10; and then conveying the connected device into a sleeve 17 through an operation machine 9, lifting the operation oil pipe 10 after the device is lowered to a preset position, opening the supporting slips 3, pressing the setting releasing packer 2 at the well head, lifting a load after setting and completing releasing. The float switch is automatically closed under the action of high pressure of the shaft, so that liquid cannot flow into the oil pipe.
And selecting a rodless oil production system or a rod oil production system according to the requirement in the subsequent pump-down operation.
When a rodless lifting system is adopted, the switch control part, the tail pipe 8 and the electric submersible pump 12 are sequentially put into a well through the continuous cable laying oil pipe 11, the speed is reduced when the position of the switch control part is 50m away from the releasing packer 2, the switch control part is lifted up for 2m after bottom detection, the switch control part is quickly connected with the cable 2, the pipe column is continuously put for more than 2m, the float switch 4 is opened through the switch control part, the production well mouth 13 is quickly installed, and well completion production is carried out.
When a rod lifting system is adopted, the switch control piece, the tail pipe 8 and the oil well pump 14 are sequentially put into a well through the oil pumping pipe 18, the speed is reduced when the position is 50m away from the releasing packer 2, the speed is raised by 1m after bottom detection, the float switch 4 is ensured to be temporarily closed, the oil pipe is hung at the well mouth, the oil pumping rod 15 is continuously put down, and when the oil pumping rod 15 reaches the position of the oil well pump 14, the pump is bumped, and the position is adjusted to hang the oil pumping rod 15 in the oil pipe (the coupling of the uppermost oil pumping rod is. Lowering oil pumping pipe 18 again and surpassing 1m, switching control piece opens float switch 4 under the oil pipe action of hanging a heavy object, installs the well head fast, connects sucker rod 15, and the regulation scour protection apart from, start beam-pumping unit 16 and produce.
When the well is repaired again or the pump is checked, the continuous cable laying oil pipe 11 or the oil pumping pipe 18 is directly lifted out, the float switch 4 is closed, the float switch 4 seals the space of the oil pumping pipe 18 at the moment, and the releasing packer 2 seals the oil sleeve annulus. The utility model discloses can not take the pressure operation in the upper portion sleeve pipe 17. The utility model discloses, effectively improved the security of operation, also improved production efficiency.
Example three:
according to a downhole switch device for controlling pressure in a wellbore shown in fig. 1, the difference from the first embodiment is that: the supporting piece adopts a supporting slip 3.
In practical use, the supporting part adopts the supporting slip 3 which is a common downhole operation tool for oil fields, and the purpose of the supporting slip is to bring the packer to a preset position, open the supporting slip by lifting or lowering the pipe column, support the inner wall of the casing pipe by means of friction force, and facilitate the pressing and setting of the subsequent packer.
Example four:
according to a downhole switch device for controlling pressure in a wellbore shown in fig. 1, the difference from the first embodiment is that: the switch control piece is a through rod 5 of a hollow conical body.
When in actual use, the switch control part adopts the technical scheme, so that the main body of the switch device can be effectively opened, and the effective control of the pressure in the shaft and the effective and smooth production are ensured.
Example five:
according to a downhole switch device for controlling the pressure in the well bore shown in FIG. 1, the difference from the fourth embodiment is that: the through rod 5 is a hollow integrated structure consisting of a cylinder at the upper part and a cone at the lower part.
When in actual use, the lower part of the through rod 5 is a conical hollow cylindrical body, so that the effect of opening the switch main body is better, and after the switch main body is opened, crude oil can be drawn out through the through rod 5, and the normal production is ensured.
Example six:
a method of controlling pressure in a wellbore for production, comprising the steps of
The method comprises the following steps: sequentially connecting a plug 6, a perforated pipe 7, a tail pipe 8, a supporting slip 3, a releasing packer 2 and a float switch 4 from bottom to top, and then connecting the plug to the lower part of an operating oil pipe 10;
step two: conveying the device connected in the step into a sleeve 17 through an operation machine 9, lifting an operation oil pipe 10 after the device is lowered to a preset position, opening a supporting slip 3, pressing a setting releasing packer 2 at the wellhead, lifting a load after setting and completing releasing;
step three: when the pressure in the shaft exceeds a preset value, selecting an oil extraction system according to the requirement of pump lowering operation; entering a fourth step when a rodless oil extraction system is required to be adopted, and entering a fifth step when a rod oil extraction system is required to be adopted;
step four: connecting a through rod 5 below a pump lower oil pipe 1, then sequentially lowering the through rod 5, the pump lower oil pipe 1 and an electric submersible pump 12 into a well through a continuous cable laying oil pipe 11, reducing the speed when the distance from a releasing packer 2 is a preset position, lifting the pipe by a preset height after bottom detection, quickly connecting a cable 20, then continuously lowering the pipe column for bottom detection, opening a float switch 4 through the through rod 5, quickly installing a production well mouth 13, and completing production;
step five: connecting a through rod 5 below a pump lower oil pipe 1, sequentially lowering the through rod 5, the pump lower oil pipe 1 and an oil well pump 14 into a well through an oil pumping pipe 18, reducing the speed when the position is a preset position away from a releasing packer 2, lifting a preset height after bottom detection, and ensuring that a float switch 4 is temporarily closed; hanging an oil pumping pipe 18 at the well mouth, continuing to put a sucker rod 15, colliding the pump when the sucker rod 15 reaches the position of the oil well pump 14, adjusting the position of the sucker rod 15 and hanging the sucker rod 15 in the well; lowering the oil pumping pipe 18 again, when the oil pumping pipe 18 exceeds the bottom detecting distance, opening the float switch 4 by the through rod 5 under the action of the suspended weight of the oil pumping pipe 18, quickly installing a well head, connecting the oil pumping rod 15, adjusting the anti-impact distance, and starting the oil pumping unit 16 for production;
step six: when the pressure in the cylinder drops to a preset value, the continuous cable laying oil pipe 11 or the oil pumping pipe 18 is directly lifted out, and the float switch 4 is closed.
Preferably, in the fourth step, the preset height of the base is 1.8-2.2 m after the base is detected.
Preferably, in the step five, the lifting height after probing is 0.8-1.2 m.
In actual use, the plug 6, the perforated pipe 7, the tail pipe 8, the supporting slip 3, the float switch 4 and the releasing packer 2 are conveyed into the casing 17 through the operation machine 9 and the operation oil pipe 10 in sequence according to the figure 3. When the float switch 4 is lowered into the casing 17 and the tool is lowered to a predetermined position, the working oil pipe 10 is lifted and lowered, and the supporting slips 3 are opened. And (3) pressing the setting releasing packer 2 at the well head, lifting the load after setting and completing releasing. At this time, the float switch 4 is closed, and the releasing packer 2 seals the oil sleeve annulus. And selecting a rodless oil production system or a rod oil production system according to the requirement in the subsequent pump-down operation. When a rodless lifting system is adopted, a through rod 5, a tail pipe 8 and an electric submersible pump 12 are sequentially lowered into a well through a continuous cable laying oil pipe 11 according to a figure 2, the speed is reduced when the position of the rodless lifting system is 50m away from a releasing packer 2, the speed is raised by 2m after bottom detection, a cable 20 is quickly connected, a pipe column is continuously lowered by more than 2m, a float switch 4 is opened through the through rod 5, a production well mouth 13 is quickly installed, and well completion production is carried out. When a rod lifting system is adopted, a through rod 5, a tail pipe 8 and an oil well pump 14 are sequentially lowered into a well through an oil pumping pipe 18 according to a graph 1, the speed is reduced when the position of the through rod is 50m away from a releasing packer, the through rod is lifted by about 1m after the bottom detection, the float switch 4 is temporarily closed, the well mouth is hung with the oil pipe, the oil pumping rod 15 is continuously lowered, and when the oil pumping rod 15 reaches the position of the oil well pump 14, the oil pumping rod is bumped and the position is adjusted to hang the oil pumping rod in the oil pipe (the coupling of the uppermost oil. And lowering the pumping oil pipe 18 for more than 1m, opening the float switch 4 by the through rod 5 under the action of the suspended weight of the oil pipe, quickly installing a well head, connecting the pumping rod 15, adjusting the anti-impact distance, and starting the pumping unit 16 for production.
When the well is repaired again or the pump is checked, the continuous cable laying oil pipe 11 or the oil pumping pipe 18 is directly lifted out, the float switch 4 is closed, the float switch 4 seals the oil pipe at the moment, and the releasing packer 2 seals the oil sleeve annulus. The wellbore can be operated without pressure in the wellbore above the wellbore opener.
The utility model discloses, the security of operation has been improved, production efficiency has also been improved.
Example seven:
a method for controlling pressure in a wellbore to produce, which is different from the sixth embodiment in that: the preset positions of the speed reduction in the fourth step and the fifth step are 45-55m away from the releasing packer 2.
In actual use, the distance from the releasing packer 2 is required to be 45-55m, and the speed is reduced. The main part is that a through rod 5 is connected under the pump, which is a main tool for opening the float switch, and the float switch is slowly closed and opened, so that the position of the float switch can be accurately determined, and the pressure in a shaft is prevented from instantly rising to cause an underground accident.
Example eight:
a method for controlling pressure in a wellbore to produce, which is different from the sixth embodiment in that: and in the fifth step, the position of the sucker rod 15 is adjusted and suspended on the oil pipe, and the sucker rod coupling on the uppermost surface of the sucker rod 15 is exposed out of the well head.
In practice, the sucker rod 15 is an important tool for the sucker rod pumping system to transmit the ground power to the downhole, and is usually connected with a polish rod and reciprocates up and down with the pumping unit 16.
The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
In the case of no conflict, a person skilled in the art may combine the related technical features in the above examples according to actual situations to achieve corresponding technical effects, and details of various combining situations are not described herein.
It should be noted that all the directional indicators (such as upper, lower, left, right, front and rear … …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the motion situation, etc. in a specific posture (as shown in the drawings), and if the specific posture is changed, the directional indicator is changed accordingly.
The foregoing is illustrative of the preferred embodiments of the present invention, and the present invention is not to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein. Any simple modification, equivalent changes and modifications made to the above embodiments according to the technical spirit of the present invention all fall within the scope of the technical solution of the present invention. The components and structures of the present embodiments that are not described in detail are well known in the art and do not constitute essential structural elements or elements.
Claims (5)
1. A downhole switching device for controlling pressure in a wellbore, comprising: comprises a switch control piece connected below an oil pipe (1) under the pump and a switch main body sealed in a sleeve (17); the switch control member is controlled to be turned on by being in contact with the switch main body.
2. A downhole switching device for controlling pressure in a wellbore according to claim 1 wherein: the switch main body comprises a releasing packer (2), a support piece and a float switch (4); the float switch (4), the releasing packer (2) and the support piece are sequentially connected from top to bottom.
3. A downhole switching device for controlling pressure in a wellbore according to claim 2 wherein: the supporting part adopts a supporting slip (3).
4. A downhole switching device for controlling pressure in a wellbore according to claim 1 wherein: the switch control piece is a through rod (5) of a hollow conical body.
5. A downhole switching device for controlling pressure in a wellbore according to claim 4 wherein: the through rod (5) is a hollow integrated structure consisting of a cylinder at the upper part and a cone at the lower part.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020706261.6U CN212671707U (en) | 2020-04-30 | 2020-04-30 | Underground switch device for controlling pressure in shaft |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202020706261.6U CN212671707U (en) | 2020-04-30 | 2020-04-30 | Underground switch device for controlling pressure in shaft |
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| Publication Number | Publication Date |
|---|---|
| CN212671707U true CN212671707U (en) | 2021-03-09 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202020706261.6U Active CN212671707U (en) | 2020-04-30 | 2020-04-30 | Underground switch device for controlling pressure in shaft |
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| Country | Link |
|---|---|
| CN (1) | CN212671707U (en) |
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2020
- 2020-04-30 CN CN202020706261.6U patent/CN212671707U/en active Active
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