Built-in centralizing device and centralizing method for polished rod sealer

Abstract

The invention belongs to the technical field of rod pumped well polish rod sealing, and discloses a polish rod sealer built-in centralizing device and a centralizing method.The polish rod sealer built-in centralizing device comprises an upper fixing base, a lower fixing base and rolling bodies, and the upper fixing base and the lower fixing base are each of an annular structure and are concentrically and fixedly connected; a plurality of grooves are formed in the inner side of the joint of the upper fixing base and the lower fixing base, the grooves of the upper fixing base and the grooves of the lower fixing base are matched to form a plurality of containing cavities, one part of each rolling body is located in the corresponding containing cavity, limited by the corresponding containing cavity and capable of rotating, and the other part of each rolling body protrudes out of the surface of the upper fixing base and the surface of the lower fixing base. According to the invention, centering linear motion of the polish rod in the stuffing box of the polish rod sealer can be realized, side extrusion and abrasion to the stuffing cannot be caused, the sealing period of the stuffing is effectively prolonged, an effective sealing effect is formed, the labor intensity of personnel is reduced, and the production efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of polished rod sealing technology for oil pumping wells, and specifically relates to a built-in straightening device and straightening method for a polished rod seal. Background Technology

[0002] Rod pump production is the most common method used in oilfield production management. Rod pump production requires the installation of a polished rod seal at the wellhead. The polished rod seal, also known as a packing box, is a key component of the wellhead in mechanically produced wells. Packing is inserted between the polished rod seal and the polished rod to provide a seal and prevent oil and gas leakage. During daily production, the continuous up-and-down movement of the polished rod generates friction with the packing. Simultaneously, well inclination deformation and wellhead misalignment exacerbate packing wear. Frequent packing replacements in some wells affect well productivity and also waste manpower, materials, and resources. Summary of the Invention

[0003] The purpose of this invention is to provide a built-in straightening device for a smooth rod seal, which enables the smooth rod to move linearly and centered in the stuffing box of the smooth rod seal, without causing lateral compression and wear on the packing, effectively extending the sealing cycle of the packing, forming an effective sealing effect, reducing the labor intensity of personnel, and improving production efficiency.

[0004] The technical solution adopted in this invention is a built-in straightening device for the smooth rod seal. The built-in straightening device includes an upper fixed seat, a lower fixed seat, and a rolling element. The upper fixed seat and the lower fixed seat are both annular structures and are concentrically fixedly connected. Several grooves are provided on the inner side of the connection between the upper fixed seat and the lower fixed seat. The grooves of the upper fixed seat and the lower fixed seat cooperate to form several receiving cavities. Part of the rolling element is located in the receiving cavity, is constrained by the receiving cavity, and can rotate. The other part of the rolling element protrudes from the surface of the upper fixed seat and the lower fixed seat.

[0005] Preferably, a light rod is inserted through the upper fixed seat and the lower fixed seat, and the surface of at least one of the protruding portions of the rolling element slides in cooperation with the surface of the light rod.

[0006] Preferably, the upper fixing seat and the lower fixing seat are detachably fixedly connected by fixing screws.

[0007] Preferably, the grooves in the upper and lower fixed seats where the rolling elements are placed are made of a hardened alloy material.

[0008] Preferably, the rolling element is a spherical ball, with a portion of the spherical ball nested inside the receiving cavity to form an embedded ball portion, and another portion being the exposed ball portion. The radius of the spherical ball is r, and the chord height of the fan-shaped cross-section of the exposed ball portion through the center of the sphere is h. <r。

[0009] Preferably, the straightening device built into the smooth rod seal is installed inside the stuffing box of the smooth rod seal, and the outer diameter of the upper fixed seat and the lower fixed seat matches the inner diameter of the stuffing box of the smooth rod seal.

[0010] Preferably, in the polished rod seal with a dual-stage sealing box, a built-in straightening device of the polished rod seal is added to each of the dual-stage stuffing boxes of the dual-stage sealing box.

[0011] Preferably, the cavity is filled with lubricating grease.

[0012] Preferably, the grooves are arranged at uniform intervals.

[0013] The present invention also provides a method for straightening a smooth rod seal with a built-in straightening device, comprising the following steps: S1. Place the built-in straightening device of the polished rod seal into the stuffing box of the polished rod seal and install it to the bottom of the stuffing box; S2. Install sealing filler on the upper part of the built-in straightening device of the smooth rod sealer; S3. The built-in straightening device and sealing packing of the smooth rod seal are pressed and compacted by the pressure cap on the packing box; S4. During the up-and-down reciprocating motion, the smooth rod is kept within the center of the stuffing box by the built-in straightening device of the smooth rod sealer, so that the smooth rod only moves up and down and does not squeeze the sealing packing laterally.

[0014] The beneficial effects of this invention are as follows: This invention ensures the alignment of the polished rod within the polished rod seal when the pumping unit drives the polished rod to reciprocate up and down. This reduces the rapid wear of the sealing packing caused by the misalignment of the polished rod, effectively extends the sealing cycle of the sealing packing, forms an effective sealing effect, and reduces the labor intensity of personnel.

[0015] This invention can significantly reduce the number of times sealing packings need to be replaced, reduce downtime, and greatly improve production efficiency.

[0016] The present invention has a simple structure and is easy to install and disassemble. The detachable upper and lower fixing seats facilitate the replacement of worn parts, reduce maintenance costs, and improve material utilization. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the built-in straightening device in the smooth rod seal of the present invention.

[0018] Figure 2 This is a partially enlarged view of the present invention.

[0019] In the diagram: 1. Upper fixed seat; 2. Spherical ball; 21. Inset part of ball; 22. Exposed part of ball; 3. Lower fixed seat; 4. Fixing screw. Detailed Implementation

[0020] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0021] Example 1 The present invention provides a built-in straightening device for the smooth rod seal. The built-in straightening device includes an upper fixed seat 1, a lower fixed seat 3, and a rolling element. The upper fixed seat 1 and the lower fixed seat 3 are both annular structures and are concentrically fixedly connected. The inner side of the connection between the upper fixed seat 1 and the lower fixed seat 3 is provided with a plurality of grooves. The grooves of the upper fixed seat 1 and the grooves of the lower fixed seat 3 cooperate to form a plurality of receiving cavities. A portion of the rolling element is located in the receiving cavity, is constrained by the receiving cavity, and can rotate. The other portion of the rolling element protrudes from the surface of the upper fixed seat 1 and the lower fixed seat 3.

[0022] Example 2 Based on Embodiment 1, a light rod is inserted into the upper fixed seat 1 and the lower fixed seat 3. When the light rod deviates and the built-in straightening device of the light rod seal takes effect, the surface of at least one of the protruding parts of the rolling element slides in cooperation with the surface of the light rod.

[0023] In a smooth rod seal with a dual-stage sealing box, a built-in straightening device is added to each of the dual-stage stuffing boxes of the dual-stage sealing box.

[0024] The grooves for accommodating the rolling elements in the upper fixed seat 1 and the lower fixed seat 3 are made of hardened alloy material.

[0025] The cavity is filled with grease, which reduces the direct contact between the rolling elements and the cavity, thereby significantly reducing friction and wear and effectively extending the service life of the device.

[0026] The upper fixed seat 1 and the lower fixed seat 3 are detachably fixed together by fixing screws 4. The detachable upper fixed seat 1 and lower fixed seat 3 facilitate the replacement of ball bearings, avoid unnecessary whole-body replacement, thereby reducing maintenance costs, improving recycling rate, and reducing resource waste.

[0027] The grooves are evenly spaced. In some more specific embodiments, both the upper fixing seat 1 and the lower fixing seat 3 are provided with 8 grooves. The 8 grooves are evenly spaced around the center of the annular structure and cooperate to form 8 receiving cavities.

[0028] Example 3 Based on Embodiment 1, as Figure 1 and Figure 2 shown, the rolling elements are spherical balls 2. A part of the spherical ball 2 is nested inside the accommodation cavity to form a ball embedded part 21, and the other part is a ball exposed part 22. The radius of the spherical ball 2 is r, and the chord height of the fan-shaped cross-section passing through the center of the ball of the ball exposed part 22 is h, where h < r, which can ensure that the ball rolls while not falling off.

[0029] The grooves for arranging the spherical balls 2 in the upper fixing seat 1 and the lower fixing seat 3 are made of alloy with hard treatment, which ensures the effective rotation of the balls and reduces the frictional resistance to the spherical balls 2.

[0030] Based on Embodiment 2, a polished rod is passed through the upper fixing seat 1 and the lower fixing seat 3. A polished rod is passed through the upper fixing seat 1 and the lower fixing seat 3. The surfaces of the protruding parts of several spherical balls 2 are all in sliding fit with the surface of the polished rod.

[0031] In some specific embodiments, the chord height h of several spherical balls 2 is the same.

[0032] Embodiment 4 Based on Embodiment 1 or Embodiment 2 or Embodiment 3, the outer diameters of the upper fixing seat 1 and the lower fixing seat 3 are matched with the inner diameter of the stuffing box of the polished rod seal. It can ensure that the built-in centralizing device of the polished rod seal of the present invention is smoothly placed into the stuffing box of the polished rod seal, playing a centralizing role.

[0033] Embodiment 5 The present invention also provides a centralizing method for the built-in centralizing device of the polished rod seal, including the following steps: S1. Place the built-in centralizing device of the polished rod seal into the stuffing box of the polished rod seal and install it to the bottom of the stuffing box.

[0034] S2. Install sealing packing on the upper part of the built-in centralizing device of the polished rod seal.

[0035] S3. Press and compact the built-in centralizing device of the polished rod seal and the sealing packing through the gland nut on the stuffing box.

[0036] S4. During the up-and-down reciprocating movement of the polished rod, due to the action of the built-in centralizing device of the polished rod seal, the polished rod only makes up-and-down reciprocating movement around the center of the stuffing box without laterally squeezing the sealing packing.

[0037] The polished rod seal of the present invention has a built-in alignment device that achieves the alignment of the polished rod through the upper fixed seat 1, the lower fixed seat 3 and the rolling element. This ensures the alignment of the polished rod in the polished rod seal when the pumping unit drives the polished rod to make up-down reciprocating motion, thereby reducing the rapid wear of the sealing packing caused by misalignment, effectively extending the sealing cycle of the sealing packing, reducing the labor intensity of personnel, reducing the number of downtimes, and improving production efficiency.

[0038] Components and structures not described in detail in the embodiments are well-known components, common structures or common means in the industry, and will not be described in detail here.

Claims

1. A built-in straightening device for a smooth rod seal, characterized in that, The built-in straightening device of the smooth rod seal includes an upper fixed seat (1), a lower fixed seat (3), and a rolling element. The upper fixed seat (1) and the lower fixed seat (3) are both annular structures and are concentrically fixed. Several grooves are provided on the inner side of the connection between the upper fixed seat (1) and the lower fixed seat (3). The grooves of the upper fixed seat (1) and the grooves of the lower fixed seat (3) cooperate to form several receiving cavities. A part of the rolling element is located in the receiving cavity, is constrained by the receiving cavity and can rotate, and the other part of the rolling element protrudes from the surface of the upper fixed seat (1) and the lower fixed seat (3).

2. The built-in straightening device of the smooth rod seal according to claim 1, characterized in that, A light rod is inserted inside the upper fixed seat (1) and the lower fixed seat (3), and the surface of at least one of the protruding parts of the rolling element slides in cooperation with the surface of the light rod.

3. The built-in straightening device of the smooth rod seal according to claim 1, characterized in that, The upper fixing seat (1) and the lower fixing seat (3) are detachably fixedly connected by fixing screws (4).

4. The photopheresis system of claim 1, wherein the photopheresis system further comprises a light source configured to emit light into the chamber. The grooves for accommodating the rolling elements in the upper fixed seat (1) and the lower fixed seat (3) are made of hardened alloy material.

5. The photopheresis system of claim 1, wherein the photopheresis system further comprises a light source configured to emit light into the treatment chamber. The rolling element is a spherical ball (2). Part of the spherical ball (2) is nested inside the receiving cavity, forming the ball inlay part (21), and the other part is the ball exposed part (22). The radius of the spherical ball (2) is r, and the chord height of the fan-shaped section of the ball exposed part (22) through the center of the ball is h. <r。 6. The in-seal polisher righting device of the polished rod as claimed in any one of claims 1-5, characterized in that, The straightening device built into the smooth rod seal is installed inside the stuffing box of the smooth rod seal, and the outer diameter of the upper fixed seat (1) and the lower fixed seat (3) matches the inner diameter of the stuffing box of the smooth rod seal.

7. The photopheresis system of claim 6, wherein the photopheresis system further comprises a light source configured to emit light into the light pipe. In a smooth rod seal with a dual-stage sealing box, a built-in straightening device is added to each of the dual-stage stuffing boxes of the dual-stage sealing box.

8. The photopheresis system of claim 1, wherein the photopheresis system further comprises a light source configured to emit light into the chamber. The cavity is filled with lubricating grease.

9. The built-in straightening device of the smooth rod seal according to claim 1, characterized in that, The grooves are arranged at uniform intervals.

10. A method for straightening a smooth rod seal with a built-in straightening device as described in claim 1, characterized in that, Includes the following steps: S1. Place the built-in straightening device of the polished rod seal into the stuffing box of the polished rod seal and install it to the bottom of the stuffing box; S2. Install sealing filler on the upper part of the built-in straightening device of the smooth rod sealer; S3. The built-in straightening device and sealing packing of the smooth rod seal are pressed and compacted by the pressure cap on the packing box; S4. During the up-and-down reciprocating motion, the smooth rod is kept within the center of the stuffing box by the built-in straightening device of the smooth rod sealer, so that the smooth rod only moves up and down and does not squeeze the sealing packing laterally.

Images