CN119825286A - Annular cement squeezing device - Google Patents
Annular cement squeezing device Download PDFInfo
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- CN119825286A CN119825286A CN202311333237.7A CN202311333237A CN119825286A CN 119825286 A CN119825286 A CN 119825286A CN 202311333237 A CN202311333237 A CN 202311333237A CN 119825286 A CN119825286 A CN 119825286A
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Abstract
The invention relates to the technical field of petroleum underground well cementation, in particular to an annular cement extrusion device. Solves the problems of long replacement time, incomplete replacement and poor quality of the return Duan Gujing existing in the existing cement extrusion method. The annular cement extruding device comprises a conveying mechanism, wherein the conveying mechanism comprises a hose, an inserting pipe and a balancing weight, the inserting pipe is connected below the hose, the bottom of the inserting pipe is sealed, the periphery of the inserting pipe is provided with a flow hole, the balancing weight is connected with the inserting pipe, and is used for applying force in the vertical direction to the hose and the inserting pipe, so that the hose and the inserting pipe are always kept in an unfolding state in the vertical direction, the inserting pipe is immersed into mud through the balancing weight arranged below the inserting pipe, and the cement paste directly flows out of the flow hole to reach an original cement layer.
Description
Technical Field
The invention relates to the technical field of petroleum underground well cementation, in particular to an annular cement extrusion device.
Background
In the well cementation process, the cement is often not enough to return due to various reasons such as lost circulation, insufficient cement usage amount and the like, so that the well cementation quality requirement is not met. Cement is not enough to return, the well cementation quality is not qualified, well crossing is not possible, and the remediation is usually completed by means of cement extrusion.
At present, cement squeezing method is commonly used, cement slurry is directly poured from a wellhead, and cement return height is increased by using cement slurry and slurry replacement. However, the method has the problems that cement slurry replacement needs to wait for the cement slurry to be precipitated to the lower part of the slurry, the replacement time is long, the cement slurry is polluted by incomplete replacement, and the quality of the extruded return Duan Gujing is poor.
Disclosure of Invention
The invention provides an annular cement extrusion device and an annular cement extrusion method, which are used for solving the problems of poor quality of Duan Gujing caused by incomplete replacement and long replacement time in the existing cement extrusion method.
In order to alleviate the technical problems, the technical scheme provided by the invention is as follows:
An annular cement extruding device comprises a conveying mechanism;
The conveying mechanism comprises a hose, a cannula and a balancing weight;
the cannula is connected below the hose, the bottom of the cannula is closed, and the periphery of the cannula is provided with a flow hole;
The balancing weight is connected to the cannula, and the balancing weight is used for applying force in the vertical direction to the hose and the cannula so that the hose and the cannula always keep the unfolded state in the vertical direction.
Still further, the method further comprises the steps of,
The cannula is inserted into the hose.
Still further, the method further comprises the steps of,
The hose is provided with an opening, and when the communication hole and the opening on the hose are in an overlapped state, the medium in the hose can flow out.
Still further, the method further comprises the steps of,
A pull rope component is arranged below the hose, and the balancing weight is connected with the pull rope component.
Still further, the method further comprises the steps of,
The pull rope assembly comprises a first pull rope and a second pull rope which are symmetrically arranged;
The lower parts of the first pull rope and the second pull rope are connected to form a contact point, and the balancing weight is connected to the contact point.
Still further, the method further comprises the steps of,
At least one balancing weight is arranged.
Still further, the method further comprises the steps of,
The device also comprises a connecting mechanism;
the connecting mechanism is detachably connected to the upper part of the conveying mechanism;
the top of the connecting mechanism is used for being connected with external grouting equipment.
Still further, the method further comprises the steps of,
The connecting mechanism comprises a union joint and a reducer joint;
the union joint is detachably connected with the reducer joint.
Still further, the method further comprises the steps of,
The reducer union is detachably connected with the hose.
A grouting system comprises the annular cement squeezing device.
In summary, the technical effects achieved by the invention are as follows:
the invention provides an annular cement squeezing device which comprises a conveying mechanism, wherein the conveying mechanism comprises a hose, an insertion pipe and a balancing weight, the insertion pipe is connected below the hose, the bottom of the insertion pipe is closed, the periphery of the insertion pipe is provided with a flow hole, the balancing weight is connected with the insertion pipe, and the balancing weight is used for applying force in the vertical direction to the hose and the insertion pipe so as to enable the hose and the insertion pipe to be always kept in an unfolded state in the vertical direction.
The annular cement extruding device provided by the invention replaces the original device for directly injecting cement slurry from a wellhead, so that the conveying mechanism directly enters the slurry, the insertion pipe is immersed into the slurry through the balancing weight arranged below the insertion pipe, the slurry can not float upwards due to high slurry density, and directly flows out of the circulation hole to reach the original cement layer.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the related art, the drawings that are required to be used in the description of the embodiments or the related art will be briefly described, and it is apparent that the drawings in the description below are some embodiments of the present invention, and other drawings may be obtained according to the drawings without inventive effort for those skilled in the art.
FIG. 1 is a schematic structural view of an annular cement extrusion device of the present invention;
Fig. 2 is a schematic view of the flow path of cement slurry.
Icon:
100-conveying mechanism, 110-hose, 120-cannula, 130-balancing weight, 140-flow hole and 150-pull rope component;
200-connecting mechanism, 210-union joint and 220-reducer joint.
300-Raw sludge layer;
400-mud.
Detailed Description
The following description of the embodiments of the present invention will be made apparent and fully in view of the accompanying drawings, in which some, but not all embodiments of the invention are shown. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
In the description of the present invention, it should be noted that the directions or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer", etc. are based on the directions or positional relationships shown in the drawings, are merely for convenience of describing the present invention and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a specific orientation, be configured and operated in a specific orientation, and thus should not be construed as limiting the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
In the description of the present invention, unless explicitly stated or limited otherwise, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected, mechanically connected, electrically connected, directly connected, indirectly connected via an intervening medium, or in communication between two elements. The specific meaning of the above terms in the present invention will be understood in specific cases by those of ordinary skill in the art.
Example 1
In the well cementation process, the current common cement extrusion method is to directly pour cement slurry from a wellhead, and cement return height is increased by using cement slurry and slurry replacement. However, the method has the problems that cement slurry replacement needs to wait for the cement slurry to be precipitated to the lower part of the slurry, the replacement time is long, the cement slurry is polluted by incomplete replacement, and the quality of the extruded return Duan Gujing is poor.
In view of the above, the present invention provides an annular cement extruding device, which comprises a conveying mechanism 100, wherein the conveying mechanism 100 comprises a hose 110, an insertion tube 120 and a balancing weight 130, the insertion tube 120 is connected below the hose 110, the bottom of the insertion tube 120 is closed, the periphery of the insertion tube 120 is provided with a flow hole 140, the balancing weight 130 is connected to the insertion tube 120, and the balancing weight 130 is used for applying a force in a vertical direction to the hose 110 and the insertion tube 120, so that the hose 110 and the insertion tube 120 always maintain an unfolded state in the vertical direction.
Because the annular cement extruding device provided by the invention replaces the original method of directly injecting cement slurry from a wellhead, the conveying mechanism 110 directly enters the slurry 400, the insertion tube 120 is immersed into the slurry 400 through the balancing weight 130 arranged below the insertion tube 120, the slurry can not float upwards due to the high density of the slurry 400, and the slurry directly flows out of the circulation hole 140 to reach the original cement layer 300.
The structure and shape of the annular cement extruding device according to this embodiment will be described in detail with reference to fig. 1-2:
As shown in fig. 1, the annular cement extruding device provided in this embodiment includes a conveying mechanism 100, wherein the conveying mechanism 100 includes a hose 110, an insertion tube 120 and a balancing weight 130, the insertion tube 120 is connected below the hose 110, the bottom of the insertion tube 120 is closed, and the periphery of the insertion tube 120 is provided with a flow hole 140, and the balancing weight 130 is connected to the insertion tube 120.
During well cementation, the conveying mechanism 100 can enter a well, and because of complex environment in the well, in order to avoid damage to the hose 110 and the insertion tube 120 caused by abrasion of external foreign matters, the hose 110 is made of a plastic material with strong toughness, the surface is wrapped by adopting a wear-resistant stainless steel tube, and the insertion tube 120 is made of the wear-resistant stainless steel tube with a certain thickness.
As shown in fig. 1, the cannula 120 is inserted into the hose 110, the hose 110 is provided with an opening, and when the communication hole 140 is in an overlapped state with the opening on the hose 110, the medium in the hose 110 can flow out;
As shown in fig. 2, when cement slurry enters the hose 110 by the external cementing equipment at a certain pressure and then flows out of the flow holes 140 on the cannula 120, because the size of the flow holes 140 is much smaller than that of the cannula 120, the cement slurry flows out in the form of spray because the pressure is not changed;
The purpose of this is that, because the slurry 400 is provided on the upper portion of the raw cement layer 300, the fluidity of the cement slurry on the lower portion is worse under the pressure of the slurry 400 on the upper portion, if the bottom is not provided with the insertion tube 120, the cement slurry is directly injected into the hose 110, after a period of injection, the cement slurry is accumulated near the hose 110 and gradually wraps the hose 110, the problem that the extrusion time is increased or the hose 110 is blocked is solved, the insertion tube 120 is used and the flow holes 140 are provided, the extruded cement slurry is extruded outwards in a spraying manner, so that the extruded cement slurry can be more uniformly covered on the raw cement layer 300, the time for extruding the cement can be effectively shortened, and the blocking problem is avoided.
As shown in fig. 1, a rope pulling assembly 150 is arranged below the hose 110, a balancing weight 130 is connected to the rope pulling assembly 150, the rope pulling assembly 150 comprises a first rope and a second rope which are symmetrically arranged, contact points are formed by connecting the bottoms of the first rope and the second rope, and the balancing weight 130 is connected to the contact points.
In order to meet the requirement that the hose 110 can smoothly enter the well through an irregular channel and smoothly enter the slurry 400, the lower end of the insertion tube 120 is connected with the balancing weight 130 by using the pull rope assembly 150, and in order to avoid the problem that the balancing weight 130 falls off due to damage and fracture of the pull rope assembly 150 caused by a complex environment in the well, the pull rope assembly 150 is preferably made of a steel wire with high wear resistance and tensile strength.
At least one weight 130 is provided according to the well depth and the height of the slurry 400.
As shown in fig. 1, the grouting device further comprises a connection mechanism 200, wherein the connection mechanism 200 is detachably connected to the upper part of the conveying mechanism 100, the top of the connection mechanism 200 is used for being connected with external grouting equipment, the connection mechanism 200 comprises a union joint 210 and a reducer joint 220, the union joint 210 is detachably connected with the reducer joint 220, and the reducer joint 220 is detachably connected with the hose 110.
The hose 110 is detachably connected with the external cementing equipment, and the external cementing equipment and the conveying mechanism 100 can be connected together by using a connecting mechanism 200 with proper size according to the interfaces of the external cementing equipment.
The specific operation steps of the invention are as follows:
first, the external cementing equipment is connected to the delivery mechanism 100 through the connection mechanism 200;
step two, putting the conveying mechanism 100 from the wellhead into the slurry 300 to enable the balancing weight 130 to enter the slurry 300;
thirdly, starting external cementing equipment;
And fourthly, after the cement paste is extruded for a period of time, the slurry gradually returns out from the wellhead, and when the cement paste overflows from the wellhead, the extrusion is completed, and the external cementing equipment is closed.
The invention has the following beneficial effects:
At the bottom of sinking conveying mechanism 100 into mud 400 through balancing weight 130, through setting up the circulation hole 140 on intubate 120 with the grout discharge, make the grout direct contact with former cement layer 300, the grout need not replace with mud 400 and can reach the purpose of squeezing the notes, has shortened the time of squeezing the notes operation, has improved well cementation quality and work efficiency.
Example two
The present embodiment includes the annular cement extruding device described in the first embodiment, so that all the beneficial effects of the annular cement extruding device in the first embodiment are not described herein.
It should be noted that the above-mentioned embodiments are merely for illustrating the technical solution of the present invention, and not for limiting the same, and although the present invention has been described in detail with reference to the above-mentioned embodiments, it should be understood by those skilled in the art that the technical solution described in the above-mentioned embodiments may be modified or some or all of the technical features may be equivalently replaced, and these modifications or substitutions do not make the essence of the corresponding technical solution deviate from the scope of the technical solution of the embodiments of the present invention.
Claims (10)
1. An annular cement extrusion device which is characterized in that:
comprises a conveying mechanism (100);
The conveying mechanism (100) comprises a hose (110), a cannula (120) and a balancing weight (130);
The insertion tube (120) is connected below the hose (110), the bottom of the insertion tube (120) is closed, and the periphery of the insertion tube is provided with a flow hole (140);
The balancing weight (130) is connected to the insertion tube (120), and the balancing weight (130) is used for applying force in the vertical direction to the hose (110) and the insertion tube (120), so that the hose (110) and the insertion tube (120) always maintain the unfolded state in the vertical direction.
2. The annular cement paste ejection apparatus of claim 1, wherein:
the cannula (120) is inserted into the hose (110).
3. The annular cement paste ejection apparatus of claim 2, wherein:
the hose (110) is provided with an opening, and when the circulation hole (140) and the opening on the hose (110) are in an overlapped state, the medium in the hose (110) can flow out.
4. An annular cement extrusion apparatus as claimed in claim 3, wherein:
a pull rope assembly (150) is arranged below the hose (110), and the balancing weight (130) is connected to the pull rope assembly (150).
5. The annular cement paste ejection apparatus of claim 4, wherein:
The pull rope assembly (150) comprises a first pull rope and a second pull rope which are symmetrically arranged;
the first pull rope and the second pull rope are connected below to form a contact point, and the balancing weight (130) is connected to the contact point.
6. The annular cement paste ejection apparatus of claim 5, wherein:
at least one of said weights (130) is provided.
7. The annular cement paste ejection apparatus of claim 6, wherein:
Also comprises a connecting mechanism (200);
the connecting mechanism (200) is detachably connected to the upper part of the conveying mechanism (100);
the top of the connecting mechanism (200) is used for being connected with external grouting equipment.
8. The annular cement paste ejection apparatus of claim 7, wherein:
The connecting mechanism (200) comprises a union joint (210) and a reducer joint (220);
The union joint (210) is detachably connected with the reducer joint (220).
9. The annular cement paste ejection apparatus of claim 8, wherein:
the reducer union (220) is detachably connected with the hose (110).
10. A grouting system comprising an annular cement extrusion apparatus as claimed in any one of claims 1 to 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311333237.7A CN119825286A (en) | 2023-10-13 | 2023-10-13 | Annular cement squeezing device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311333237.7A CN119825286A (en) | 2023-10-13 | 2023-10-13 | Annular cement squeezing device |
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| CN119825286A true CN119825286A (en) | 2025-04-15 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202311333237.7A Pending CN119825286A (en) | 2023-10-13 | 2023-10-13 | Annular cement squeezing device |
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- 2023-10-13 CN CN202311333237.7A patent/CN119825286A/en active Pending
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