A cementing casing centralizer

Abstract

The utility model discloses a well cementing casing centralizer, its main body structure adopts spring steel seamless steel tube after cutting, and the integral type main body structure that is formed after the overall processing of further processing is formed, the integral type main body structure includes: the upper sleeve and lower sleeve of accommodating and being set in the casing at upper and lower ends, and multiple centralizing ribs are arranged longitudinally between the upper sleeve and lower sleeve and are located in the middle part, multiple centralizing ribs are arranged on the outer circumferential surface of upper sleeve and lower sleeve along the circumferential direction of upper sleeve and lower sleeve and are integrally formed and are connected with upper sleeve and lower sleeve, and the centralizing rib is outwardly inclined from upper and lower ends to the axis of casing in the middle part, a stress groove is arranged in the middle position of each centralizing rib to increase the reset force after deformation, and fluid flow channel is formed between the adjacent two centralizing ribs. The application can guarantee the casing centralization, smoothly enter the well, and is not easy to be damaged, and the well cementing quality is guaranteed.

Description

Technical Field

[0001] This utility model relates to a cementing casing centralizer. Background Technology

[0002] During drilling operations, because the wellbore has a certain inclination angle, especially in directional and horizontal wells, after the casing is inserted into the well, it tends to stick close to the bottom edge of the wellbore under the influence of gravity. During cementing, the drilling fluid at the bottom edge is not easily displaced and removed, affecting the filling effect of the cement slurry in the annulus and resulting in poor annulus cementing quality. To overcome this casing sticking phenomenon and improve the casing's centering within the wellbore, a casing centralizer needs to be installed on the casing to ensure it remains as centered as possible within the wellbore.

[0003] The problems with the casing centralizers currently in use are: the centralizer has a large starting force, which results in high friction when the casing is inserted into the well, affecting the smooth insertion of the casing; the centralizer has a small restoring force, resulting in poor casing capacity after the casing is inserted into the well and poor casing centering effect; welded and braided casing centralizers are prone to breakage and disintegration during the insertion process, thus losing their casing centralizing function. Utility Model Content

[0004] The purpose of this utility model is to provide a cementing casing centralizer that solves and compensates for the shortcomings of current technology, making it easy to install on site, securely fixed, not easily damaged, with low starting force and high reset force, and good centralizing effect.

[0005] To achieve the above technical objectives, this utility model provides a cementing casing centralizer, wherein: its main structure is an integral main structure formed by cutting a spring steel seamless steel pipe and then further processing it; the integral main structure includes: an upper sleeve and a lower sleeve located at the upper and lower ends, which are accommodated and sleeved on the casing, and a plurality of centralizing ribs located in the middle and arranged longitudinally between the upper and lower sleeves. The plurality of centralizing ribs are arranged parallel to each other and spaced apart along the circumferential direction of the upper and lower sleeves and are integrally formed and connected to the upper and lower sleeves; the centralizing ribs are inclined outward from the upper and lower ends toward the middle relative to the axis of the casing, and a stress groove is provided in the middle of each centralizing rib to increase the restoring force after deformation, and a fluid flow channel is formed between two adjacent centralizing ribs.

[0006] This utility model provides a cementing casing centralizer, which adopts an integral structure and processing mode, and ensures the casing centering. While ensuring that the casing can be smoothly inserted into the well, the centralizer can not only effectively improve the casing centering, but also make it convenient to use in the field, not easily damaged, and ensure cementing quality.

[0007] As a further improvement, the straightening rib is in the shape of an arc, and the maximum outer diameter of the arc is located in the middle of the straightening rib. The middle position is the position of the maximum outer diameter of the integral main structure, and the outer diameter at the maximum outer diameter position is consistent with the outer diameter of the drill bit forming the wellbore.

[0008] As a further improvement, the straightening ribs are arranged symmetrically outward from the middle position.

[0009] As a further improvement, the stress groove is an inwardly concave arc groove.

[0010] As a further improvement, the circumferential width of the straightening rib is 40-60mm, and the thickness is the same as that of the upper and lower sleeves. The straightening rib is processed into an arc shape after heat treatment.

[0011] As a further improvement, the number of the aforementioned straightening ribs is even.

[0012] As a further improvement, the straightening tendons are four or six.

[0013] As a further improvement, the height of the integral main structure is between 400-800mm, and its processing material is 65Mn spring steel seamless steel pipe.

[0014] As a further improvement, the height of the upper and lower sleeves is 150-180mm, the inner diameter is 1.05-1.20 times the outer diameter of the sleeve, and the outer diameter is consistent with the outer diameter of the female coupling of the sleeve.

[0015] As a further improvement, all of the aforementioned straightening ribs are processed to extend at an angle with the same angle direction, so that the fluid forms a swirling flow when returning upward in the flow channel between two adjacent straightening ribs.

[0016] This utility model provides a cementing casing centralizer that ensures smooth casing insertion into the well and centralizes the casing, thereby improving cementing quality. Attached Figure Description

[0017] Figure 1 This is a front view of the present utility model;

[0018] Figure 2 This is a side view of an example of this utility model;

[0019] Figure 3 This is a top view of the upper sleeve of this utility model.

[0020] Reference numerals: 11 Upper sleeve; 12 Straightening rib; 13 Stress groove; 14 Lower sleeve. Detailed Implementation

[0021] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0022] like Figures 1 to 3 As shown, this utility model provides a cementing casing centralizer, wherein: its main structure is an integral main structure formed by cutting a spring steel seamless steel pipe and then further processing it; the integral main structure includes: an upper sleeve 11 and a lower sleeve 14 located at the upper and lower ends and fitted onto the casing, and a plurality of centralizing ribs 12 located in the middle and arranged longitudinally between the upper and lower sleeves. The plurality of centralizing ribs 12 are arranged parallel to each other and spaced apart along the circumferential direction of the upper and lower sleeves and are integrally formed and connected to the upper and lower sleeves; the centralizing ribs 12 are inclined outward from the upper and lower ends toward the middle relative to the axis of the casing, and a stress groove 13 is provided in the middle position of each centralizing rib to increase the restoring force after deformation, and a fluid flow channel is formed between two adjacent centralizing ribs.

[0023] This utility model provides a cementing casing centralizer, which adopts an integral structure and processing mode, and ensures the casing centering. While ensuring that the casing can be smoothly inserted into the well, the centralizer can not only effectively improve the casing centering, but also make it convenient to use in the field, not easily damaged, and ensure cementing quality.

[0024] As a further improvement, the straightening rib is in the shape of an arc, and the maximum outer diameter of the arc is located in the middle of the straightening rib. The middle position is the position of the maximum outer diameter of the integral main structure, and the outer diameter at the maximum outer diameter position is consistent with the outer diameter of the drill bit forming the wellbore.

[0025] As a further improvement, the straightening ribs are arranged symmetrically outward from the middle position.

[0026] As a further improvement, the stress groove 13 is an inwardly concave arc groove.

[0027] As a further improvement, the circumferential width of the straightening rib 12 is 40-60mm, and its thickness is consistent with the thickness of the upper and lower sleeves. The straightening rib is processed into an arc shape after heat treatment.

[0028] As a further improvement, the plurality of the aforementioned straightening ribs 12 are arranged in an even number.

[0029] As a further improvement, the straightening tendons 12 are four or six.

[0030] As a further improvement, the height of the integral main structure is between 400-800mm, and its processing material is 65Mn spring steel seamless steel pipe.

[0031] As a further improvement, the height of the upper and lower sleeves is 150-180mm, the inner diameter is 1.05-1.20 times the outer diameter of the sleeve, and the outer diameter is consistent with the outer diameter of the female coupling of the sleeve.

[0032] As a further improvement, all of the aforementioned straightening ribs are processed to extend at an angle with the same angle direction, so that the fluid forms a swirling flow when returning upward in the flow channel between two adjacent straightening ribs.

[0033] This utility model provides a cementing casing centralizer that ensures smooth casing insertion into the well and centralizes the casing, thereby improving cementing quality. By centralizing the casing, it enhances displacement efficiency and cement bonding quality, thus improving cementing quality, meeting the needs of oil and gas field exploration and development, extending the life of oil and gas wells, and increasing economic benefits.

[0034] The upper sleeve, lower sleeve, and straightening rib are made of seamless spring steel pipes, which are cut and then further processed into a single unit. The main structure is integral. This integral straightening device is robust, strong, provides excellent straightening effect, and is not easily damaged. The upper and lower sleeves are the uppermost and lowermost circular sleeves of the straightening device, integrally connected to the straightening rib. Their main function is to secure the straightening device onto the sleeves. The integral straightening device is firmly fixed onto the sleeves and is not easily damaged.

[0035] The stress groove of the centralizing rib is located in the middle of the centralizing rib, which is also the position where the outer diameter of the centralizer is the largest. This stress groove ensures that the centralizer has good restoring force and improves the centralizer's ability to maintain its centralizing capacity even after deformation when the well inclination angle is large.

[0036] like Figures 1 to 3 As shown, the sleeve straightener includes an upper sleeve 11, a lower sleeve 14, and a straightening rib 12. All of these components are made of seamless steel pipe of 65Mn spring steel. The straightening rib 12 is provided with a bent straightening rib stress groove 13.

[0037] In this embodiment 1, the upper sleeve 11 and the lower sleeve 14 are fitted onto the sleeve. An integrally formed straightening rib 12 is provided between the upper sleeve 11 and the lower sleeve 14. Multiple straightening ribs 12 are provided, and all the straightening ribs 12 are arranged at intervals along the circumference of the upper sleeve 11 and the lower sleeve 14 on their outer circumferential surfaces, forming a sleeve. A flow channel is formed between adjacent straightening ribs 12 to allow fluid to flow through. In other embodiments, the straightening ribs can be welded onto the upper and lower sleeves.

[0038] In this embodiment, the height of the integral elastic centralizer is between 400-800mm, and its main body is made of 65Mn spring steel seamless steel pipe. Its main structure is integral. In this embodiment, the upper sleeve 11 and the lower sleeve 14 are the uppermost and lowermost circular sleeves of the centralizer, with a height of 150-180mm. The inner diameter is 1.05-1.20 times the outer diameter of the sleeve used, and the outer diameter is consistent with the outer diameter of the sleeve's female coupling.

[0039] In this embodiment, the centralizing rib 12 is made of seamless 65Mn spring steel pipe through cutting and heat treatment. It is integral with the upper and lower sleeves. Four to six centralizing ribs 12 are evenly cut along the 360° circumference of the seamless steel pipe. The circumferential width of the centralizing rib 12 is 40-60mm, and its thickness is consistent with the thickness of the upper and lower sleeves. After heat treatment, the centralizing rib 12 is processed into an arc shape. The largest outer diameter of the arc is located in the middle of the centralizing rib, and the outer diameter of the largest outer diameter is consistent with the outer diameter of the drill bit forming the wellbore. A stress groove 13 is provided at this location. The space formed between two adjacent centralizing ribs 12 serves as a fluid channel.

[0040] In this embodiment, the stress groove 13 is located in the middle of the straightening rib 12. The stress groove 13 is formed by hot working the straightening rib 12 and then bending it with a special tool. After quenching, the strength of the stress groove 13 is increased to ensure that the straightener has a good restoring force and improve the straightening ability of the straightener after deformation when the well inclination angle is large.

[0041] The casing centralizer of this utility model is mainly used in cementing operations in the fields of oil and gas development, coalbed methane development, and gas storage. It can be fixed to the outside of the casing during field application and has broad prospects. Moreover, the casing centralizer of this utility model has a simple structure, is easy to operate on site, and is conducive to large-scale promotion and application.

[0042] During cementing operations, the casing centralizer is fitted onto the casing and secured with a retaining ring, allowing it to be lowered into the well along with the casing. During this lowering process, the centralizing ribs 12 on the upper sleeve 11 and lower sleeve 14 function as the casing itself, preventing direct contact between the casing and the wellbore. Once the casing is lowered to the designated position, they help to center the casing and improve its alignment. When well flushing begins, the annular fluid passes through the casing centralizer and returns upwards through the channel between the two centralizing ribs 12. After well flushing and subsequent cementing and completion operations are completed, the casing centralizer remains downhole along with the casing.

[0043] This utility model of casing centralizer achieves two functions: wellbore mud cake destruction and removal, and casing centralization. It improves displacement efficiency and cement bonding quality, thereby improving cementing quality, extending the life of oil and gas wells, and thus improving economic benefits.

[0044] Embodiment 2 of the casing centralizer of this utility model: The difference between this embodiment and Embodiment 1 is that in Embodiment 1, each centralizing rib 12 extends along the axial direction of the sleeve. In this embodiment, each centralizing rib 12 can be processed to extend at an angle with the same angle direction, so that the fluid can form a swirling flow when returning upward in the flow channel between two adjacent centralizing ribs 12, further improving the cementing displacement efficiency and creating favorable conditions for improving cementing quality.

[0045] This utility model provides an integral casing centralizer that simultaneously performs the functions of casing and breaking down and removing mud cake from the well wall. By centralizing the casing, it improves displacement efficiency and cement bonding quality, thereby improving cementing quality, meeting the needs of oil and gas field exploration and development, extending the life of oil and gas wells, and increasing economic benefits.

[0046] It should be understood that the scope of protection sought by this utility model is not limited to the non-limiting embodiments, which are merely illustrative examples. The substantive scope of protection claimed in this application is further embodied in the scope provided by the independent claims and their dependent claims.

Claims

1. A cementing casing centralizer, characterized in that: Its main structure is an integral structure formed by cutting seamless spring steel pipes and then processing them as a whole. The integral main structure includes: an upper sleeve and a lower sleeve located at the upper and lower ends and fitted onto the sleeve, and a plurality of straightening ribs located in the middle and arranged longitudinally between the upper and lower sleeves. The plurality of straightening ribs are arranged parallel to each other and spaced apart along the circumferential direction of the upper and lower sleeves and are integrally formed and connected to the upper and lower sleeves. The straightening ribs are formed in an outward inclination relative to the axis of the sleeve from the upper and lower ends toward the middle. A stress groove is provided in the middle of each straightening rib to increase the restoring force after deformation. A fluid flow channel is formed between two adjacent straightening ribs.

2. A cementing casing centralizer according to claim 1, characterized in that: The straightening rib is in the shape of an arc, and the largest outer diameter of the arc is located in the middle of the straightening rib. The middle position is the position of the largest outer diameter of the integral main structure, and the outer diameter at the position of the largest outer diameter is consistent with the outer diameter of the drill bit that forms the wellbore.

3. A cementing casing centralizer according to claim 2, characterized in that: The straightening ribs are arranged symmetrically outward from the middle position.

4. A cementing casing centralizer according to claim 3, characterized in that: The stress groove is an inwardly concave circular arc groove.

5. A cementing casing centralizer according to claim 4, characterized in that: The circumferential width of the straightening rib is 40-60mm, and its thickness is the same as that of the upper and lower sleeves. The straightening rib is processed into an arc shape after heat treatment.

6. A cementing casing centralizer according to claim 5, characterized in that: The number of straightening ribs mentioned above is even.

7. A cementing casing centralizer according to claim 6, characterized in that: The supporting tendons are four or six in number.

8. A cementing casing centralizer according to claim 1, characterized in that: The height of the integral main structure is between 400-800mm, and its processing material is 65Mn spring steel seamless steel pipe.

9. A cementing casing centralizer according to claim 8, characterized in that: The upper and lower sleeves have a height of 150-180mm, an inner diameter that is 1.05-1.20 times the outer diameter of the sleeve, and an outer diameter that is consistent with the outer diameter of the female coupling of the sleeve.

10. A cementing casing centralizer according to claim 1, characterized in that: The multiple straightening ribs are all processed to extend at an angle and have the same angle direction. When the fluid flows upward in the flow channel between two adjacent straightening ribs, it forms a swirling flow.

Images