CN220036612U - Elastic centralizer - Google Patents

Abstract

The utility model belongs to the technical field of well fixing and completion tools in petroleum and natural gas industries, and particularly relates to an elastic centralizer. The elastic centralizer comprises a main body and a centralizing block, wherein the centralizing block is provided with a degradable surface layer, and the elastic centralizer further comprises a groove formed in the circumference of the main body, an elastic element arranged in the groove and a limiting compression ring pressed at two ends of the elastic element and the centralizing block. After the centralizer meets and hinders, when satisfying degradation condition, through the top layer degradation of righting the piece to reduce the external diameter of righting the piece, and then reduce xiao Fu centralizer's whole external diameter, thereby reduce centralizer sand card tubular column's risk, and then do benefit to the play of tubular column.

Description

Elastic centralizer

Technical Field

The utility model belongs to the technical field of well fixing and completion tools in petroleum and natural gas industries, and particularly relates to an elastic centralizer.

Background

With the continuous deep development of oil and gas fields, directional wells, highly deviated wells and horizontal wells are gradually developed. When a high-inclination well and a horizontal well are used for running a layered production string, the packer sealing element is easily contacted with the inner wall of the casing and generates friction due to the existence of angles and inclinations, so that the casing or the packer sealing element is worn. Therefore, in order to prevent the packer sealing element from contacting the casing wall when the packer sealing element goes down the well, an elastic centralizer with larger outer diameter is usually connected in series in a matched manner so as to ensure that the packer is centered as much as possible during operation; when the pipe column stays underground for a long time and sand is discharged from an oil layer, the elastic centralizer with larger outer diameter is easy to clamp the pipe column, and the workload and difficulty of construction operation are increased.

The utility model patent in China with publication number CN207436947U and publication date 2018, month 6 and day 1 discloses an elastic pipe column centralizer, which comprises a main body and a plurality of longitudinal main body grooves formed in the outer wall of the main body, wherein supporting blocks (centralizing blocks) are arranged in the main body grooves, leaf springs are arranged between the supporting blocks and the bottoms of the main body grooves, two ends of each supporting block are limited by hoops, and the hoops are fixed on the main body by pins. According to the scheme, the maximum outer diameter of the whole centralizer does not exceed the inner diameter of the shaft under the natural state, no resistance is formed on the pipe column descending well, and when the clamping resistance such as deformation or wax precipitation of the shaft is met, the supporting block can compress the leaf spring for recovery, so that the pipe column is not blocked. However, when sand is produced from the reservoir, there is still a risk that the outer diameter of the support blocks is too large to clamp the pipe string, even if the support blocks have fully compressed the leaf springs.

The Chinese patent with publication number CN204827267U and publication day 2015 of 12 month 2 discloses a wash pipe righting device and a righting body thereof, wherein the righting body comprises a floating piece (righting block) and a plate spring which is assembled between the inner side of the floating piece and a main sleeve body and is used for pushing the floating piece outwards, the plate spring is propped between an inner concave surface of an arched part of the floating piece and the bottom surface of a guiding concave part, and an elastic vault of the plate spring is matched with the inner concave surface of the arched part of a bent plate and is arched outwards along the radial direction of the main sleeve body. The external diameter of the floating piece is changed by the inward shrinkage and the outward shrinkage of the floating piece on the main sleeve body, so that the floating piece can flexibly pass through the deformed diameter-reducing part in a manner of the inward shrinkage of the floating piece when encountering the deformed diameter-reducing part in the sleeve. But when it encounters the formation, there is also a risk that the float has fully retracted, but still a sand stuck string due to the structural influence of the float.

Disclosure of Invention

The utility model aims to provide an elastic centralizer, which solves the problem that the existing elastic centralizer still has the risk of sand clamping pipe columns after being fully contracted.

In order to achieve the above purpose, the elastic centralizer of the utility model adopts the following technical scheme:

an elastomeric centralizer includes a body and a centralizer block having a degradable skin layer.

The beneficial effects of the technical scheme are that: according to the utility model, by improving the prior art, the degradable surface layer is arranged on the righting block, after the centralizer encounters resistance, when the degradation condition is met, the surface layer of the righting block can be degraded, so that the outer diameter of the righting block is reduced, the overall outer diameter of the xiao Fu centralizer is further reduced, the risk of sand clamping the pipe column of the centralizer is further reduced, and the pipe column is further facilitated to be lifted out.

Further, the whole body of the centralizing block is a degradable centralizing block.

The beneficial effects of the technical scheme are that: by means of the setting, the overall outer diameter of the xiao Fu centralizer can be reduced to the greatest extent by the aid of the integrally degraded centralizing blocks, so that the risk of sand blocking of the centralizer on the pipe column is reduced, and the pipe column is lifted out.

Further, the material of the degradable surface layer is polyglycolic acid material.

The beneficial effects of the technical scheme are that: the polyglycolic acid material has good biodegradability, only generates water and carbon dioxide after degradation, and does not pollute the working surface and the environment.

Further, the degradable surface layer is inclined at the upper end and the lower end of the righting block.

The beneficial effects of the technical scheme are that: the guide structures with inclined planes are formed at the upper end and the lower end of the righting block, so that the righting device can smoothly adjust the righting outer diameter when encountering the change of the well diameter during use, and the situation that the righting device is clamped at the change of the well diameter is avoided.

Further, the device also comprises a groove arranged in the circumferential direction of the main body, an elastic element arranged in the groove and a limiting compression ring pressed at two ends of the elastic element and the righting block.

The beneficial effects of the technical scheme are that: the elastic element can axially slide along the main body to realize the shrinkage or expansion of the elastic element, and the limiting compression ring ensures that the elastic element and the centralizing block act within a limited range, so that the elastic element and the centralizing block are prevented from being separated from the main body.

Further, the elastic element is provided with sliding parts at two ends, the limiting compression ring is provided with a compression joint part used for limiting the elastic element, two ends of the groove are provided with sinking grooves, and the sliding parts slide in the sinking grooves and are in sliding contact with the compression joint part.

The beneficial effects of the technical scheme are that: by means of the arrangement, the two ends of the elastic element can slide in the sinking groove through the cooperation of the limiting compression ring and the groove, so that enough space for compression extension and expansion shortening is reserved in the axial direction, the elastic element cannot deviate from the groove, and the elastic element is prevented from deviating from after the righting block is degraded.

Further, the sliding portion is a protrusion toward the center of the main body.

The beneficial effects of the technical scheme are that: the device has simple structure, is convenient for processing the elastic element and is also convenient for realizing the stop fit in the sinking groove.

Further, the righting block is provided with grooves which cooperate with the resilient elements.

The beneficial effects of the technical scheme are that: the arrangement is simple in structure, and the centering block and the elastic element are convenient to mutually cooperate.

Further, the elastic element and the centralizing block are arranged in the same direction or opposite directions.

The beneficial effects of the technical scheme are that: the elastic element and the centering block are easy to realize synchronous actions, and can be guaranteed to synchronously deform in a telescopic or expanding mode, so that elastic supporting force of the elastic element to the centering block in the deformation process is effectively guaranteed, and centering of a device using the centering block is guaranteed.

Further, the number of the centralizing blocks is 3-6.

The beneficial effects of the technical scheme are that: by the arrangement, the stress balance of the centralizer is kept by using fewer centralizing blocks, so that the centralizing function of the centralizer is kept.

Drawings

FIG. 1 is a schematic view of the structure of an elastic centralizer of the present utility model;

fig. 2 is a cross-sectional view A-A of fig. 1.

In the figure: 1. a main body; 11. a groove; 111. sinking grooves; 2. limiting compression rings; 21. a crimping part; 22. a pressure limiting part; 3. centralizing blocks; 31. a righting part; 32. a limit part; 33. a groove; 4. an elastic element; 41. a protrusion; 42. a supporting part.

Detailed Description

The present utility model will be described in further detail with reference to the drawings and examples, in order to make the objects, technical solutions and advantages of the present utility model more apparent. It should be understood that the particular embodiments described herein are illustrative only and are not intended to limit the utility model, i.e., the embodiments described are merely some, but not all, of the embodiments of the utility model. The components of the embodiments of the present utility model generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.

Thus, the following detailed description of the embodiments of the utility model, as presented in the figures, is not intended to limit the scope of the utility model, as claimed, but is merely representative of selected embodiments of the utility model. All other embodiments, which can be made by a person skilled in the art without making any inventive effort, are intended to be within the scope of the present utility model.

It is noted that relational terms such as "first" and "second", and the like, may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Moreover, terms such as "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one … …" or the like does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The features and capabilities of the present utility model are described in further detail below in connection with the examples.

Example 1 of the resilient centralizer of the utility model,

as shown in fig. 1 and 2, the elastic centralizer of the present utility model includes a main body 1, a limiting press ring 2, a centralizing block 3 and an elastic member 4.

4 axial grooves 11 are uniformly formed in the circumferential direction of the main body 1, sinking grooves 111 are formed in two ends of the grooves 11, and external threads are formed in the outer wall of the main body 1 along the opening edge of the grooves 11; the upper end of the main body 1 is provided with internal threads, and the lower end is provided with external threads. The number of the elastic elements 4 and the centralizing blocks 3 is consistent with that of the grooves 11, the elastic elements 4 and the centralizing blocks 3 which are in one-to-one correspondence are arranged in each groove 11, the elastic elements 4 and the centralizing blocks 3 are sequentially arranged in the grooves 11 from inside to outside, and the outer sides of the elastic elements 4 are far away from the center of the main body 1, and are in contact fit with the centralizing blocks 3.

The centralizing block 3 is arched and is provided with a groove 33 for being matched with the elastic element 4, and comprises a centralizing part 31 far away from the center of the main body 1 and limiting parts 32 extending from the centralizing part 31 to two ends, wherein the limiting parts 32 are provided with step surfaces; the upper and lower both ends of righting piece 3 are the inclined plane, and the linkage segment between righting portion 31 and the spacing portion 32 is the inclined plane promptly, has formed guide structure like this, runs into the well bore change and can smoothly right the adjustment when being convenient for the centralizer when using to avoid the card in well bore change department. In this embodiment, the centralizing block 3 is integrally cast from a hydrolysable polyethylene material and then formed. After the centralizer is lowered to the position along with the packer and is set, the centralizer blocks are gradually hydrolyzed into water and carbon dioxide after a certain time in a downhole hot water environment, so that the outer diameter of the elastic centralizer is reduced, and the subsequent extraction of the underground layered production string is facilitated.

The elastic element 4 is arcuate and comprises a support 42 remote from the centre of the body 1 and protrusions 41 at both ends of the elastic element, the protrusions 41 constituting the sliding portions of the elastic element. In this embodiment, the elastic element 4 is a leaf spring.

One end of the limiting compression ring 2 is provided with a step surface, so that a limiting part 22 for limiting the righting block 3 is formed; the tip of the other end is the inclined plane that the external diameter reduces gradually, has formed guide structure like this, runs into the diameter change and can smoothly right the adjustment of external diameter when conveniently right the ware and use, avoids the card in diameter change department. The inner wall surface of the limiting pressing ring 2 forms a pressure contact portion 21 for limiting the elastic element 4. The inner wall of the limiting press ring 2 is also provided with threads, and the limiting press ring 2 is respectively connected with threads at two ends of the groove 11 of the main body 1.

In this embodiment, the protrusion 41 of the elastic element 4 is slidably disposed in the recess 111 of the recess 11, and the protrusion 41 of the elastic element 4 forms a stop fit with the inner wall of the recess 111, so that the elastic element 4 is slidably disposed in the recess 11; the inner wall surface of the limiting pressing ring 2 is in sliding contact with the protrusion 41 of the elastic element 4, so that the protrusion 41 of the elastic element 4 can slide in the sinking groove 111 through the matching of the limiting pressing ring 2 and the sinking groove 111, and enough space for compression extension and expansion shortening is provided in the axial direction, so that the elastic element 4 cannot be separated from the groove, and separation of the elastic element 4 after the righting block 3 is degraded is avoided. The length of the elastic element 4 is larger than that of the righting block 3, so that the structure of the limit pressing ring 2 is convenient to set, and the limit of the elastic element 4 and the righting block 3 can be realized through the step surface and the inner wall surface of the limit pressing ring 2; the dimensions of the elastic element 4 are adapted to the dimensions of the recess 11, so that it is ensured that the outer diameter of the centralizer can be automatically adjusted within a certain range in the change of contraction and expansion of the elastic element 4, and in other embodiments, the length of the elastic element can be smaller than or equal to the length of the righting block, and the lengths of the two can be satisfied as required.

In this embodiment, the elastic element 4 and the centering block 3 are disposed in the same direction, and the support portion 42 of the elastic element 4 is in contact fit with the centering portion 31 of the centering block 3 in the groove 33 and stretches or expands in the radial direction of the main body 1, so that the two are deformed in a stretching or expanding manner synchronously. The limit part 22 of the limit compression ring 2 and the limit part 32 of the centralizing block 3 form stop fit through a step surface, and a deformation gap of the centralizing block 3 is arranged between the limit part 32 of the centralizing block 3 and the step surface of the limit part 22 of the limit compression ring 2, so that the centralizing block 3 is stably assembled through the stop fit of the limit compression ring 2 and the support of the elastic element 4 in a natural state; when the righting block 3 is stressed to deform, the elastic element 4 changes along with the deformation of the righting block 3, and a sufficient elastic supporting force is always maintained, so that the device using the centralizer is always positioned in the center of the casing.

Example 2 of the resilient centralizer of the utility model:

in example 1 of the resilient centralizer, the whole body of the centralizer block is made of a degradable material. In this embodiment, the righting block includes a righting block body and a degradable surface layer embedded on the surface of the righting block body, where the righting block body may be a rigid material, or may be other degradable materials different from the degradable surface layer, and the degradable surface layer may be embedded with the righting block body by vulcanization or other manners.

Example 3 of the resilient centralizer of the utility model:

in example 1 of the resilient centralizer, the material of the degradable skin layer is a polyglycolic acid material. In this embodiment, the material of the degradable surface layer is polylactic acid (PLA) material or other degradable polymer material.

Example 4 of the resilient centralizer of the utility model:

in embodiment 1 of the resilient centralizer, the resilient element is provided with protrusions at both ends towards the centre of the main body. In this embodiment, the two ends of the elastic element may not be provided with protrusions, and correspondingly, the two ends of the groove are not provided with sinking grooves.

Example 5 of the resilient centralizer of the utility model:

in example 1 of the resilient centralizer, the centralizer block is provided with grooves that mate with the resilient member. In this embodiment, the righting block is no longer provided with grooves that cooperate with the elastic elements; in other embodiments, the elastic element may be engaged with the righting segment and the support segment of the righting block by fixing the two.

Example 6 of the resilient centralizer of the utility model:

in example 1 of the resilient centralizer, the righting block is disposed in the same direction as the resilient member. In this embodiment, the centering block and the elastic element are disposed opposite to each other, that is, the opening direction of the centering block and the opening direction of the elastic element are disposed opposite to each other, so that the matching structure of the centering block and the elastic element needs to be adaptively adjusted to ensure synchronous actions of the centering block and the elastic element.

Example 7 of the resilient centralizer of the utility model:

in example 1 of the resilient centralizer, the number of righting blocks is 4. In this embodiment, the number of righting blocks may be 3, 5, or 6; in other embodiments, the number of righting blocks may be set to an appropriate number as desired.

The above description is only a preferred embodiment of the present utility model, and the patent protection scope of the present utility model is defined by the claims, and all equivalent structural changes made by the specification and the drawings of the present utility model should be included in the protection scope of the present utility model.

Claims (9)

1. An elastic centralizer, includes main part and righting piece, its characterized in that: the righting block is provided with a degradable surface layer, and further comprises a groove arranged in the circumferential direction of the main body, an elastic element arranged in the groove and a limiting compression ring pressed at two ends of the elastic element and the righting block.

2. The resilient centralizer of claim 1, wherein: the whole body of the centralizing block is a degradable centralizing block.

3. The resilient centralizer of claim 1 or 2, wherein: the degradable surface layer is made of polyglycolic acid material.

4. A resilient centraliser as claimed in claim 3, wherein: the degradable surface layer is inclined at the upper end and the lower end of the righting block.

5. The resilient centralizer of claim 1, wherein: the elastic element is provided with sliding parts at two ends, the limiting compression ring is provided with a compression joint part used for limiting the elastic element, two ends of the groove are provided with sinking grooves, and the sliding parts slide in the sinking grooves and are in sliding contact with the compression joint part.

6. The resilient centralizer of claim 5, wherein: the sliding part is a protrusion toward the center of the main body.

7. The resilient centralizer of claim 1, wherein: the righting block is provided with grooves which cooperate with the elastic elements.

8. The resilient centralizer of claim 7, wherein: the elastic element and the righting block are arranged in the same direction or opposite directions.

9. The resilient centralizer of claim 8, wherein: the number of the centralizing blocks is 3-6.