Hollow rod centralizer

Abstract

The utility model discloses a hollow rod centralizer which comprises an upper connector and a lower connector, the upper connector and the lower connector are both of a hollow structure, the end, connected with the lower connector, of the upper connector is provided with an upper connector installation part which retracts in the radial direction, and a limiting part is formed on the side, away from the lower connector, of the upper connector installation part. The side, close to the upper connector, of the lower connector is provided with a lower connector connecting part containing the upper connector installing part, the upper connector installing part and the lower connector connecting part are assembled and connected, the upper connector installing part between the limiting part and the lower connector connecting part is sleeved with a bearing, and the bearing is sleeved with a bearing anti-abrasion sleeve. A bearing sealing head is assembled between the bearing and the lower connector, the outer diameter of the bearing anti-abrasion sleeve is larger than the maximum outer diameter of the upper connector and the maximum outer diameter of the lower connector, and the technical problem that an oil pipe is damaged in the prior art is solved.

Description

Technical Field

[0001] The utility model belongs to the technical field of oil and gas exploitation, and particularly relates to a hollow rod centralizer. Background Art

[0002] At present, domestic oil and gas field development adopts rod-type oil and gas systems and rodless oil pumping systems. For rod-type oil pumping systems, the technology has been continuously improved through more than 100 years and is relatively mature. However, in order to reduce the problem of eccentric wear of rods and pipes, sucker rod centralizers are generally installed on the sucker rods, or coated oil pipes and sprayed sucker rods are used. In low-liquid wells, when the pump is lowered into large-angle or horizontal sections, there is a serious eccentric wear problem of rods and pipes, and the working life is short.

[0003] In the development of coalbed methane, fly ash will enter the pumping system with the produced fluid, inevitably causing damage to the pump. Generally, ground-driven screw pumps are used to drain water and produce gas, and sucker rod centralizers are installed in the rod column. There is also the problem of eccentric wear on the oil pipe. Patented technology CN117703286A adopts a three-claw hinged roller structure, which is suitable for straightening casing in drilling operations. Due to the large size of the hinge and roller, it is not suitable for straightening and wear prevention in the oil pipe; patented technology CN201059165Y adopts an anti-corrosion and wear-resistant layer in contact with the oil pipe. Although the main body of the centralizer does not wear less, the oil pipe is easily worn through; CN2886058Y has a wear-resistant coating structure on the surface of the main body of the centralizer, which will not cause damage to the hollow sucker rod at the deflection point in the oil well, and there is also wear on the oil pipe. Utility Model Content

[0004] The utility model aims to provide a hollow rod centralizer to solve the technical problem of oil pipe damage in the prior art.

[0005] The technical solution adopted by the utility model to solve its technical problems is:

[0006] A hollow rod straightener comprises: an upper joint and a lower joint, both of which are hollow structures, one end of the upper joint connected to the lower joint has a radially indented upper joint mounting portion, the upper joint mounting portion forms a limiting portion on a side away from the lower joint, and the lower joint has a lower joint connecting portion accommodating the upper joint mounting portion on a side close to the upper joint, the upper joint mounting portion and the lower joint connecting portion are assembled and connected, a bearing is sleeved on the upper joint mounting portion between the limiting portion and the lower joint connecting portion, a bearing anti-wear sleeve is sleeved on the outside of the bearing, a bearing sealing head is assembled between the bearing and the lower joint, and the outer diameter of the bearing anti-wear sleeve is greater than the maximum outer diameter of the upper joint and the lower joint.

[0007] The utility model provides a hollow rod centralizer, wherein the bearing and the upper joint mounting portion are in interference fit, and the bearing and the bearing anti-wear sleeve are in clearance fit.

[0008] The utility model discloses a hollow rod centralizer. The lower joint connecting part is circumferentially provided with an anti-rotation pin which is connected with the upper joint mounting part.

[0009] The utility model provides a hollow rod centralizer, wherein the depth of the anti-rotation pin is 0.5-1mm deeper than the threaded hole in which the anti-rotation pin is installed.

[0010] The utility model discloses a hollow rod centralizer, wherein the joint surfaces of the bearing anti-wear sleeve and the bearing sealing head and the upper joint mounting part are all provided with sealing grooves, and sealing rings are installed in the sealing grooves.

[0011] The utility model discloses a hollow rod centralizer, wherein the bearing is a deep groove ball bearing.

[0012] The beneficial effects of the utility model are as follows: a hollow rod centralizer is proposed, which reduces the friction coefficient by adopting bearing rolling friction between the hollow rod and the oil pipe, thereby achieving the effect of not easily wearing the hollow rod and the oil pipe and extending the pump inspection cycle; by setting an anti-rotation pin and extending its bottom by 0.5-1mm, it can achieve fastening while having little effect on the strength of the upper joint; by setting a bearing anti-wear sleeve and a bearing sealing head, the bearing space is sealed, so that the bearing can be fully lubricated and friction can be reduced. At the same time, the structure of the application is simple, reliable and easy to process. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present invention will be further described below with reference to the accompanying drawings and embodiments, in which:

[0014] Figure 1 It is a schematic diagram of an embodiment of the utility model. DETAILED DESCRIPTION

[0015] In order to make the purpose, technical scheme and advantages of the embodiment of the utility model clearer, the technical scheme in the embodiment of the utility model will be clearly and completely described below in conjunction with the drawings in the embodiment of the utility model. Obviously, the described embodiment is a part of the embodiment of the utility model, not all of the embodiments. It should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the utility model.

[0016] like Figure 1As shown, a hollow rod centralizer comprises: an upper joint 100 and a lower joint 600, both of which are hollow structures, and one end of the upper joint 100 connected to the lower joint 600 has a radially indented upper joint mounting portion 110, and the upper joint mounting portion 110 forms a limiting portion 120 on the side away from the lower joint 600, and the lower joint 600 has a lower joint connecting portion 610 for accommodating the upper joint mounting portion 110 on the side close to the upper joint 100, and the upper joint mounting portion 110 and the lower joint connecting portion 610 are assembled and connected, and a bearing 200 is sleeved on the upper joint mounting portion 110 between the limiting portion 120 and the lower joint connecting portion 610, and a bearing anti-wear sleeve 300 is sleeved on the outer side of the bearing 200, and a bearing sealing head 400 is assembled between the bearing 200 and the lower joint 600, and the outer diameter of the bearing anti-wear sleeve 300 is greater than the maximum outer diameter of the upper joint 100 and the lower joint 600.

[0017] It should be noted that the upper end of the upper joint 100 is connected to the hollow rod through a hollow rod thread, and the lower end has an upper joint installation part 110 connected and sealed with the lower joint connection part 610 through a plane tight fit, and thread sealant is applied when connecting the threads.

[0018] In a preferred embodiment of the utility model, the bearing 200 and the upper joint mounting portion 110 are interference fit, and the bearing 200 and the bearing anti-wear sleeve 300 are clearance fit. Through the setting of the bearing 200, when the hollow rod is rotated, the inner ring of the bearing 200 and the upper joint 100 do not move relative to each other, and lubricating oil is injected into the bearing 200, which rotates through the steel ball and the outer ring of the bearing.

[0019] In a preferred embodiment of the present invention, the lower joint connecting portion 610 is circumferentially provided with an anti-rotation pin 700 to connect with the upper joint mounting portion 110 , and is fastened by the anti-rotation pin 700 to prevent disengagement.

[0020] In a preferred embodiment of the present invention, the depth of the anti-rotation pin 700 is 0.5-1 mm deeper than the threaded hole in which it is installed, so that it can be tightened while having little effect on the strength of the upper joint 100 .

[0021] In the preferred embodiment of the utility model, the joint surfaces of the bearing anti-wear sleeve 300 and the bearing sealing head 400 and the upper joint mounting portion 110 are all provided with sealing grooves, and the sealing grooves are provided with sealing rings 800. The bearing anti-wear sleeve 300 has two functions, one is to protect the outer ring of the bearing 200, and the other is to seal the lubricating oil in the bearing 200. Since it is the same pressure system, even if the sealing ring 800 fails, the inflow of liquid and the overflow of lubricating oil are not much, which basically does not affect the rotation of the bearing 200.

[0022] In a preferred embodiment of the present invention, the bearing 200 is a deep groove ball bearing.

[0023] In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0024] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances. In addition, in the description of the present utility model, unless otherwise specified, "plurality" means two or more.

[0025] It should be understood that those skilled in the art can make improvements or changes based on the above description, and all these improvements and changes should fall within the scope of protection of the claims attached to the utility model.

Claims

1. A hollow rod centralizer, characterized in that: include: An upper joint (100) and a lower joint (600), wherein the upper joint (100) and the lower joint (600) are both hollow structures, wherein one end of the upper joint (100) connected to the lower joint (600) comprises a radially indented upper joint mounting portion (110), wherein a limiting portion (120) is formed on a side of the upper joint mounting portion (110) away from the lower joint (600), and a side of the lower joint (600) close to the upper joint (100) comprises a lower joint connecting portion (610) for accommodating the upper joint mounting portion (110), wherein the upper joint mounting portion (110) is provided at a position where the upper joint mounting portion (110) is located. The upper joint mounting portion (110) and the lower joint connecting portion (610) are assembled and connected; a bearing (200) is sleeved on the upper joint mounting portion (110) between the limiting portion (120) and the lower joint connecting portion (610); a bearing anti-wear sleeve (300) is sleeved on the outside of the bearing (200); a bearing sealing head (400) is assembled between the bearing (200) and the lower joint (600); and an outer diameter of the bearing anti-wear sleeve (300) is greater than the maximum outer diameter of the upper joint (100) and the lower joint (600).

2. A hollow rod centralizer according to claim 1, characterized in that: The bearing (200) and the upper joint mounting portion (110) are in an interference fit, and the bearing (200) and the bearing anti-wear sleeve (300) are in a clearance fit.

3. A hollow rod centralizer according to claim 1, characterized in that: The lower joint connection portion (610) is circumferentially provided with an anti-rotation pin (700) which is connected to the upper joint installation portion (110).

4. A hollow rod centralizer according to claim 3, characterized in that: The depth of the anti-rotation pin (700) is 0.5-1 mm deeper than the threaded hole in which it is installed.

5. The hollow rod centralizer according to claim 1, characterized in that: The joint surfaces of the bearing anti-wear sleeve (300) and the bearing sealing head (400) with the upper joint mounting portion (110) are all provided with sealing grooves, and a sealing ring (800) is installed in the sealing groove.

6. A hollow rod centralizer according to claim 1, characterized in that: The bearing (200) is a deep groove ball bearing.

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