Holding type bridging coupling oil pipe centralizer

Abstract

The utility model discloses an embracing type bridging coupling oil pipe centralizer which is formed by oppositely splicing a front semi-cylindrical structural body and a rear semi-cylindrical structural body which are symmetrical in structure, the structural bodies are of an integrated structure, and the two structural bodies are clamped through a plurality of steel belts. Each structural body is formed by sequentially connecting a small tooth block, an upper closing groove, a large tooth block, a middle closing groove, a middle structure, a middle closing groove, a large tooth block, an upper closing groove and a small tooth block from top to bottom; and the small tooth block, the upper closing groove, the large tooth block and the middle closing groove are all semi-cylindrical. The outer diameters of the small tooth block, the large tooth block and the middle structure are equal, and the height of the small tooth block is smaller than that of the large tooth block; the sum of the outer diameter of the upper closing groove and the thickness of the steel belt and the sum of the outer diameter of the middle closing groove and the thickness of the steel belt are equal to the outer diameter of the middle structure. The whole structure is easy to achieve, convenient to install and not prone to displacement. In addition, the manufacturing cost is low, and meanwhile the device can still be repeatedly used after pump inspection and well repair.

Description

TECHNICAL FIELD

[0001] The utility model belongs to coalbed methane drainage well downhole equipment technical field relates to a kind of downhole oil pipe centralizers in coalbed methane drainage with rod lifting process, especially a kind of embracing type jumper coupling oil pipe centralizer, it is used to strengthen the centralization and deviation wear protection of downhole oil pipe string. BACKGROUND

[0002] In the development process of coalbed methane well, it is usually necessary to use rod or rodless lifting process to drain and extract in the downhole oil pipe and various drainage equipment. This gas recovery method reduces the pressure of coal seam through oil pipe drainage to promote coalbed methane resolution, and produces gas in the annulus between oil pipe and production casing, thereby completing the extraction of coalbed methane.

[0003] Whether it is rod lifting process or rodless lifting process, drainage and pressure reduction are needed through oil pipe in the process of coalbed methane exploitation, so the oil pipe plays an important role in the process of coalbed methane drainage. In the process of coalbed methane drainage, the oil pipe is located in the production casing, and the oil pipe, downhole drainage pump and other matching parts form an oil pipe string through orderly and sequential connection to achieve the effect of drainage and pressure reduction and coalbed methane extraction.

[0004] In the current rod lifting process, the drainage pump is usually located at the bottom of the oil pipe string, and is suspended at the specified design depth according to the production layer characteristics of the target coal seam and the well type characteristics of the coalbed methane drainage well. The sucker rod in the rod lifting process is connected to the moving parts of the drainage pump body inside the oil pipe. At the same time, the cable is lowered to the designated position outside the oil pipe string to install the downhole pressure gauge for monitoring various downhole drainage data, and then adjusting the operating parameters of the drainage pump to achieve real-time control of the drainage intensity of the coalbed methane well. The oil pipe string is always in periodic vibration under the influence of the operation of the drainage pump in the production casing, which is easy to produce friction with the production casing and cause wear and tear, so the oil pipe should be kept as centered as possible to reduce wear and tear and ensure the continuity of coalbed methane drainage and the safety of drainage equipment, thus the role of oil pipe centralizer.

[0005] The oil pipe centralizer used in the current coalbed methane drainage production process is divided into two categories according to whether it is jumper coupling: one is non-jumper coupling centralizer, which is mostly installed in a sleeved manner and closely fits on the oil pipe body, and this type of centralizer mostly uses rubber or other composite materials as the main body and is fixed by pins or pins. The advantage is simple structure and easy installation, but the main problem is that this type of centralizer is prone to position shifting after long-term use due to wear and tear, so it cannot achieve the function of protecting the oil pipe at the specified position, and this shortcoming is more obvious when used in inclined well section, which is easy to cause oil pipe deviation and lead to oil pipe damage, affecting the safety of drainage construction.

[0006] The second type is a cross-over coupling centralizer, which is installed on the coupling of two oil pipes or on the oil pipe body, and is mainly made of rust-proof metal material and fixed by a pin or a pin sheet, and an anchor pin is used to install various clamping support pads made of rubber or composite material. The advantage is that the external structure has high strength and is not prone to shifting, but the main problem is that the number of internal clamping support pads is small, the anchor pin is prone to damage and falling off during long-term wear and tear, thereby reducing the centralizing effect of the centralizer, and the centralizer cannot be reused due to the damage and falling off of the clamping support pads during subsequent pump inspection and well repair, thereby increasing the maintenance cost of the drainage and production.

[0007] Therefore, the utility model aims at solving the problems and deficiencies of the above-mentioned cross-over coupling centralizer. Utility model content

[0008] The utility model discloses a kind of embracing cross-over coupling oil pipe centralizers, to solve the problems such as prone to shifting, anchor pin long-term wear and tear easy to fall off, poor reliability and cannot be reused in the oil pipe centralizer used in the existing coalbed gas well drainage.

[0009] In order to achieve the above-mentioned purpose, the technical scheme adopted by the utility model is as follows:

[0010] A kind of embracing cross-over coupling oil pipe centralizer is made by the relative combination of two structure symmetrical semicylindrical structural bodies, and the structural body is an integral structure, and a plurality of steel belts are used to clamp between the two structural bodies;

[0011] Each structural body is sequentially connected by small tooth block from top to bottom, upper joint groove, large tooth block, middle joint groove, middle structure, middle joint groove, large tooth block, upper joint groove and small tooth block;

[0012] Small tooth block, upper joint groove, large tooth block and middle joint groove are semicylindrical, and after the corresponding small tooth block, upper joint groove and large tooth block of the two structural bodies are relatively combined into cylindrical, they are used to be sleeved outside the oil pipe to be centralized, and their inner diameters are equal and matched with the outer diameter of the oil pipe to be centralized;After the corresponding middle joint grooves of the two structural bodies are relatively combined into cylindrical, they are used to be sleeved outside the oil pipe to be centralized, and the inner diameters of the two middle joint grooves are matched with the outer diameter of the oil pipe to be centralized;After the two middle structures of the structural body are combined into cylindrical, they are used to be sleeved outside the coupling of the oil pipe to be centralized, and the inner diameter is matched with the outer diameter of the coupling of the oil pipe;

[0013] The outer diameters of small tooth block, large tooth block and middle structure are equal, and the height of small tooth block is less than that of large tooth block;The sum of the outer diameter of upper joint groove and the thickness of steel belt, and the sum of the outer diameter of middle joint groove and the thickness of steel belt are equal to the outer diameter of middle structure.

[0014] Further, the outer walls of the small tooth blocks and the large tooth blocks are uniformly provided with three ribs, and after the two structures are spliced, six ribs on the two small tooth blocks are symmetrically distributed along the central axis of the structure, and six ribs on the two large tooth blocks are symmetrically distributed along the central axis of the structure.

[0015] Further, all the ribs are trapezoidal structures with the width gradually decreasing in the direction away from the small tooth block or the large tooth block, the outermost width is half of the innermost width; the width of the ribs of the small tooth block and the ribs of the large tooth block is consistent, and the length is different, the uppermost length of the small tooth block is 1 / 4 of the uppermost length of the large tooth block.

[0016] Further, the two middle structure side walls are uniformly and symmetrically provided with a total of four flow guide grooves in the circumferential direction.

[0017] Further, the flow guide groove is a circular arc structure.

[0018] The beneficial effects of the utility model are:

[0019] 1. Simple overall structure, convenient to install

[0020] Only two symmetrical integrated half-cylinder structures are needed, and only the upper joint groove and the middle holding groove are clamped by the steel band during installation, so that the structure and operation are simple, and the installation is convenient.

[0021] 2. Not prone to shifting

[0022] The inner diameter difference between the middle structure of the centralizer and the middle holding groove makes the centralizer clamp at the joint of the oil pipe, and cannot move up and down, thereby preventing the shifting caused by the movement or vibration of the oil pipe.

[0023] 3. Low manufacturing cost, and can be reused after pump inspection and well repair

[0024] The material used in the centralizer is only nitrile rubber, which has excellent oil resistance, heat resistance and wear resistance, and the material price is relatively low. Since it is an integrated structure, the vulnerable parts such as tooth blocks are prominent, which increases the degree of wear resistance during coalbed methane production, so that it can be reused after pump inspection and well repair. BRIEF DESCRIPTION OF DRAWINGS

[0025] Figure 1 is a schematic view of the holding type cross-over joint oil pipe centralizer after installation of the utility model;

[0026] Figure 2 is a front view of the holding type cross-over joint oil pipe centralizer of the utility model;

[0027] Figure 3 is a left view of the holding type cross-over joint oil pipe centralizer of the utility model;

[0028] Figure 4 This is a top view of the clamping cross-joint oil pipe stabilizer of this utility model;

[0029] This centralizer consists of two completely symmetrical structures installed by interlocking with each other. Figures 2-4 These are three views of the uprighting device in a vertical position with its two structures joined together.

[0030] The meanings of the labels in the diagram are as follows:

[0031] 11. Oil pipe; 12. Structure, 12-1. Small tooth block, 12-2. Upper engagement groove, 12-3. Large tooth block, 12-4. Middle engagement groove, 12-5. Guide groove, 12-6. Centralizer middle structure, 12-7. Installation joint. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be described in detail below with reference to the accompanying drawings and specific embodiments.

[0033] Figures 2-4 These are three views of the main body of the utility model "A Clamping-Type Pipe Centralizer", showing the front of the front structure of the centralizer in the clamped state (the front is...). Figure 1 The orientation of the front of structure 12 as shown in the installed state (not described again below) is the main view of the structure.

[0034] like Figures 1-4 As shown, the clamping cross-joint oil pipe straightener of this utility model is composed of two symmetrical semi-cylindrical structures 12 spliced ​​together. The structure 12 is an integral structure, and multiple steel strips are used to clamp the two structures 12.

[0035] Each structure 12 is formed by connecting the small tooth block 12-1, the upper jaw groove 12-2, the large tooth block 12-3, the middle jaw groove 12-4, the middle structure 12-6, the middle jaw groove 12-4, the large tooth block 12-3, the upper jaw groove 12-2, and the small tooth block 12-1 in sequence from top to bottom;

[0036] The small tooth block 12-1, the upper joint groove 12-2, the large tooth block 12-3 and the middle joint groove 12-4 are all semicylindrical, and the corresponding small tooth block 12-1, upper joint groove 12-2 and large tooth block 12-3 of the two structures 12 are relatively jointed into a cylindrical shape and used for sleeving outside the oil pipe 11 to be straightened, and the inner diameters of the three are equal and in transition fit with the outer diameter of the oil pipe 11 to be straightened; the corresponding middle joint grooves 12-4 of the two structures are relatively jointed into a cylindrical shape and used for sleeving outside the oil pipe 11 to be straightened, and the inner diameters of the two middle joint grooves 12-4 are matched with the outer diameter of the oil pipe 11 to be straightened; and the two middle structures 12-6 of the structures 12 are relatively jointed into a cylindrical shape and used for sleeving outside the coupling of the oil pipe 11 to be straightened, and the inner diameter is matched with the outer diameter of the coupling of the oil pipe 11;

[0037] The outer diameters of the small tooth block 12-1, the large tooth block 12-3 and the middle structure 12-6 are all equal, the height of the small tooth block 12-1 is smaller than that of the large tooth block 12-3; the sum of the outer diameter of the upper joint groove 12-2 and the thickness of the steel band and the sum of the outer diameter of the middle joint groove 12-4 and the thickness of the steel band are all equal to the outer diameter of the middle structure 12-6;

[0038] The above-mentioned utility model is installed on the coupling of the clamped oil pipe by the two completely symmetrical structures 12 through the steel band. Among them, the middle structure 12-6 can be closely fitted on the oil pipe coupling, and part of it is fitted on the oil pipe 11 above and below the coupling. After the installation, the straightening function of the straightener is borne by the small tooth block 12-1 and the large tooth block 12-3, and the outer diameters of the small tooth block 12-1 and the large tooth block 12-3 are much larger than the outer diameter of the oil pipe, and they are closely fitted on the oil pipe 11, and at the same time, the outer diameter of the middle structure 12-6 is larger than the outer diameter of the oil pipe coupling, and it can also play a certain straightening role on the oil pipe 11.

[0039] The fixing function of the straightener is borne by the upper joint groove 12-2, the middle joint groove 12-4, the steel band and the middle structure 12-6, and the two structures 12 are closed by being clamped in the corresponding upper joint groove 12-2 and middle joint groove 12-4 through the steel band, and the inner diameters of the two middle joint grooves 12-4 are consistent with the outer diameter of the oil pipe 11, and the inner diameter of the middle structure 12-6 is consistent with the outer diameter of the oil pipe coupling (the outer diameter of the oil pipe is much smaller than the outer diameter of the coupling), so that the two symmetrical structures 12 can be closely fitted on the oil pipe coupling after installation, and the difference between the inner diameters of the middle structure 12-6 and the middle joint groove 12-4 of the straightener makes the straightener clamped at the coupling of the oil pipe 11 and unable to move up and down, thereby preventing the oil pipe from moving or vibrating and causing the position to change, and at the same time, it can also be reused.

[0040] Specifically, the outer wall of the small tooth block 12-1 and the large tooth block 12-3 is uniformly distributed with three ribs, and after the two structures 12 are combined, the six ribs on the two small tooth blocks 12-1 are symmetrically distributed along the central axis of the structure 12, and the six ribs on the two large tooth blocks 12-3 are symmetrically distributed along the central axis of the structure 12.

[0041] All the ribs are trapezoidal structures with the width gradually decreasing in the direction away from the small tooth block 12-1 or the large tooth block 12-3, and the outermost width is half of the innermost width; the width of the ribs of the small tooth block 12-1 and the large tooth block 12-3 is consistent, and the length is different, and the length of the uppermost part of the small tooth block 12-1 is 1 / 4 of the length of the uppermost part of the large tooth block 12-3.

[0042] Preferably, the two middle structures 12-6 are uniformly and symmetrically distributed with a total of four flow guide grooves 12-5 along the circumference; preferably, the flow guide groove is a circular arc structure, and when the centralizer of the utility model is installed on the oil pipe 11, the flow guide groove 12-5 plays a role of guiding the gas-liquid in the wellbore.

[0043] Figure 2 The front features of the centralizer of the utility model in the vertical state are shown, and the dashed lines of the upper part and the lower part show the inner diameter of the structure 12, which is consistent with the outer diameter of the matched oil pipe; the inner diameter of the middle dashed line shows the inner diameter of the middle structure 12-6, which is consistent with the outer diameter of the matched oil pipe coupling. It can be seen from the upper and lower part and the middle dashed line that the middle structure 12-6 of the centralizer can wrap the oil pipe coupling, and the inner diameter difference between the upper and lower structures and the middle structure of the centralizer of the utility model clamps the oil pipe coupling to make it not easy to occur.

[0044] The figure can more clearly see the distribution of the upper joint groove 12-2 and the middle joint groove 12-4: symmetrically distributed along the middle part of the structure 12 to both sides, the joint groove is the position of the steel band of the centralizer of the utility model for clamping, and the width is preferably consistent. It can be seen from the figure that the outer diameter of the part where the joint groove is located is obviously smaller than the outer diameter of the surrounding structure, which can effectively prevent the steel band used for clamping from moving back and forth, and is beneficial to strengthening the stability of the centralizer structure.

[0045] Figure 3 The side features in the vertical state are shown, and the installation joint 12-7 after the two structures 12 are embraced can be obviously seen. The figure can also further show the positional relationship and structural symmetry of each tooth block and each joint groove.

[0046] Figure 4The figure shows the plan view of the centralizer in vertical standing state, the installation joint 12-7 between the two half-split structures 12 can be seen, which is used to mark the contact of the two structures 12. Because the big tooth blocks 12-3 and the small tooth blocks 12-1 are distributed in the same direction, the shape and height are consistent, so only 6 symmetrical ribs can be seen in the plan view. At the same time, the height of the rib and the outer diameter of the middle structure 12-6 are consistent, which together play the role of centralizing. Figure 4 The upper flow guide groove 12-5 is symmetrically distributed outside the middle structure 12-6 of the centralizer, and there are two flow guide grooves on one structure 12, a total of four flow guide grooves.

[0047] Specifically, the structure 12 is made of nitrile rubber, which has excellent oil resistance, heat resistance and wear resistance. The steel belt used in installation is a stainless steel belt with various specifications, which is a mature product on the market and will not be described in detail.

[0048] The installation operation steps of the clamping type cross-over coupling oil pipe centralizer are as follows:

[0049] (1) Close the two structures 12 tightly on the coupling of the oil pipe 11, so that the top joint 12-2 and the middle joint 12-4 of the centralizer are on the same horizontal plane, so that the two middle structures 12-6 can just clamp the entire oil pipe coupling, thereby realizing that the two structures 12 clamp the entire oil pipe coupling;

[0050] (2) Wind the steel belt around the two corresponding upper joints 12-2 and the two corresponding middle joints 12-4 respectively, and tighten it with the tightening pliers to complete the installation of the centralizer;

[0051] (3) When the centralizer of the utility model needs to be disassembled, only the steel belt needs to be opened.

Claims

1. A gripped jumper collar tubing centralizer, characterized by, Two semicircular cylindrical structural bodies (12) are oppositely combined, the structural body (12) is an integral structure, and a plurality of steel bands are used for clamping between the two structural bodies (12); Each structural body (12) is sequentially connected from top to bottom by small tooth blocks (12-1), upper matching grooves (12-2), large tooth blocks (12-3), middle matching grooves (12-4), middle structural bodies (12-6), middle matching grooves (12-4), large tooth blocks (12-3), upper matching grooves (12-2) and small tooth blocks (12-1); The small tooth blocks (12-1), the upper matching grooves (12-2), the large tooth blocks (12-3) and the middle matching grooves (12-4) are all semicircular cylindrical, after the corresponding small tooth blocks (12-1), the upper matching grooves (12-2) and the large tooth blocks (12-3) of the two structural bodies (12) are oppositely combined into a cylindrical shape, they are used for sleeving outside the oil pipe (11) to be straightened, their inner diameters are equal and match the outer diameter of the oil pipe (11) to be straightened; after the corresponding middle matching grooves (12-4) of the two structural bodies are oppositely combined into a cylindrical shape, they are used for sleeving outside the oil pipe (11) to be straightened, the inner diameters of the two middle matching grooves (12-4) match the outer diameter of the oil pipe (11) to be straightened; after the two middle structural bodies (12-6) of the structural body (12) are oppositely combined into a cylindrical shape, they are used for sleeving outside the coupling of the oil pipe (11) to be straightened, and the inner diameter thereof matches the outer diameter of the coupling of the oil pipe (11); The outer diameters of the small tooth blocks (12-1), the large tooth blocks (12-3) and the middle structural bodies (12-6) are all equal, the height of the small tooth block (12-1) is less than that of the large tooth block (12-3); the sum of the outer diameter of the upper matching groove (12-2) and the thickness of the steel band, and the sum of the outer diameter of the middle matching groove (12-4) and the thickness of the steel band are all equal to the outer diameter of the middle structural body (12-6).

2. The embracing cross-over collar tubing centralizer of claim 1 wherein, The outer walls of the small tooth blocks (12-1) and the large tooth blocks (12-3) are uniformly distributed with three ribs, after the two structural bodies (12) are combined, the six ribs on the two small tooth blocks (12-1) are symmetrically distributed along the central axis of the structural body (12), and the six ribs on the two large tooth blocks (12-3) are symmetrically distributed along the central axis of the structural body (12).

3. The embracing cross-over collar tubing centralizer of claim 2, wherein, All the ribs are trapezoidal structures with the width gradually decreasing in the direction away from the small tooth block (12-1) or the large tooth block (12-3), the outermost width is half of the innermost width; the widths of the ribs of the small tooth block (12-1) and the large tooth block (12-3) are consistent, and the lengths are different, the uppermost length of the small tooth block (12-1) is 1 / 4 of the uppermost length of the large tooth block (12-3).

4. The embracing cross-over coupling tubing centralizer of any one of claims 1 to 3, wherein, The side walls of the two middle structural bodies (12-6) are uniformly and symmetrically distributed with a total of four flow guide grooves (12-5) in the circumferential direction.

5. The embracing cross-over collar tubing centralizer of claim 4, wherein, The flow guide grooves are circular arc structures.

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