A sealing protective sleeve for the push rod of a pipe jacking machine

Abstract

This utility model discloses a sealing protective sleeve for a push rod of a pipe jacking machine, relating to the field of pipe jacking machine technology. It includes a jacking cylinder body and a push rod built into the jacking cylinder body. A sealing protective sleeve assembly is provided between the push rod and the jacking cylinder body. This assembly includes a first sealing protective sleeve, and multiple first sealing rings are provided between the first sealing protective sleeve and the inner wall surface of the jacking cylinder body. A scraper ring and a second sealing ring are sequentially provided between the first sealing protective sleeve and the push rod along the direction of movement. This utility model, through the scraper ring and the second sealing ring provided between the push rod and the jacking cylinder body, enables the push rod to bidirectionally remove mud and sand particles during reciprocating motion, protecting the sealing components from being scratched by mud and ensuring continued sealing effectiveness.

Description

Technical Field

[0001] This utility model relates to the field of pipe jacking machine technology, specifically to a sealing protective sleeve for a pipe jacking machine push rod. Background Technology

[0002] In the construction of urban underground pipeline networks, pipe jacking machines are core equipment, using a pusher system to push pipe sections into the ground one by one, achieving trenchless construction. The pusher sealing sleeve is a key component preventing mud, water, and sand from entering the hydraulic system; its reliability directly affects the equipment's operational safety and construction efficiency.

[0003] Existing pipe jacking machine push rod sealing sleeves mostly use single-layer rubber or heat-shrinkable material. In water-rich sand layers or high water pressure environments, the pressure of mud and water can easily cause gaps to form between the sealing sleeve and the push rod, creating leakage channels. For example, in environments with a permeability coefficient greater than 1×10⁻⁶, -4 In sand layers with a density of cm / s, traditional EPDM rubber protective sleeves, due to insufficient elastic modulus, cannot adaptively compensate for gaps through deformation, leading to mud and water seeping into the push rod hydraulic system, causing cylinder corrosion, seal wear, and even jacking jamming failure. Utility Model Content

[0004] The purpose of this utility model is to provide a sealing protective sleeve for the push rod of a pipe jacking machine. By setting a sealing protective sleeve assembly between the push rod and the body of the jacking cylinder, the sealing element can be protected from being scratched by mud and sludge when the push rod is pushed forward or retracted due to the function of the scraper ring and the second sealing ring, thus continuing to ensure the sealing effect.

[0005] This utility model is achieved through the following technical solution:

[0006] A sealing protective sleeve for a push rod of a pipe jacking machine includes a jacking cylinder body and a push rod built into the jacking cylinder body, wherein a sealing protective sleeve assembly is provided between the push rod and the jacking cylinder body;

[0007] The sealing sleeve assembly includes a first sealing sleeve, with a plurality of first sealing rings disposed between the first sealing sleeve and the inner wall surface of the jacking cylinder body, and a scraper ring and a second sealing ring disposed sequentially between the first sealing sleeve and the push rod along the direction of movement.

[0008] In this design, multiple first sealing rings between the first sealing protective sleeve and the inner wall of the cylinder can effectively prevent external mud and water from seeping in through the gap between the protective sleeve and the cylinder. The scraper ring and the second sealing ring arranged sequentially along the direction of movement between the first sealing protective sleeve and the push rod can first remove mud and sand particles attached to the surface of the push rod during the reciprocating motion of the push rod, preventing hard particles from scratching the second sealing ring. Then, the superimposed sealing effect of at least two second sealing rings can significantly improve the sealing structure's resistance to mud and water pressure. At the same time, through the synergistic effect of the scraper ring and the sealing ring, the risk of seal failure caused by particle wear is reduced, thereby ensuring the sealing performance and reliability of the push rod hydraulic system in complex formations.

[0009] As a further solution to the sealing protection sleeve, in order to further enhance the sealing structure's resistance to mud and water pressure, the number of the second sealing rings is at least two.

[0010] As a further embodiment of the sealing protective sleeve, the scraper rings are arranged in pairs, and all the second sealing rings are located between the scraper rings.

[0011] In this design, by arranging scraper rings in pairs and placing all the second sealing rings between them, a composite protective structure of "scraping-sealing-scraping" is formed. The paired scraper rings can remove hard particles such as mud, sand, and gravel adhering to the surface of the push rod from both directions during the reciprocating motion of the push rod, preventing particles from entering the sealing ring area with the push rod. The second sealing rings are concentrated between the two pairs of scraper rings, which keeps them in a relatively clean environment, reducing wear and scratches caused by direct contact between particles and the sealing rings. At the same time, the scraper rings' ability to block fluid flow reduces the direct impact of mud and water pressure on the sealing rings.

[0012] As a further embodiment of the sealing sleeve, the sealing sleeve assembly further includes a second sealing sleeve, wherein at least one third sealing ring is provided between the second sealing sleeve and the inner wall surface of the jacking cylinder body, and at least one fourth sealing ring is provided between the second sealing sleeve and the push rod.

[0013] In this design, the third sealing ring between the second sealing sleeve and the inner wall of the jacking cylinder body can further prevent external mud and water from leaking through the gap outside the first sealing sleeve, forming the first barrier; while the fourth sealing ring between the second sealing sleeve and the push rod adds an extra sealing barrier on the basis of the slag scraping ring and the second sealing ring of the first sealing sleeve, which is especially suitable for scenarios with extremely high sealing reliability requirements in high water pressure or complex formations.

[0014] As a further solution for the sealing protective sleeve, the fourth sealing ring is a shaft Yxd sealing ring, which can adapt to the slight radial displacement during the push rod movement process, and enhance the dynamic adaptability and stability of the sealing system.

[0015] As a further embodiment of the sealing sleeve, the sealing sleeve assembly also includes a second sealing sleeve, and a sliding cavity is provided between the push rod and the jacking cylinder body. The second sealing sleeve can slide along the sliding cavity, which is in communication with external hydraulic oil.

[0016] In this solution, a dynamic hydraulic compensation sealing structure is formed by setting a sliding cavity that communicates with external hydraulic oil between the push rod and the body of the jacking cylinder, and allowing the second sealing sleeve to slide along the sliding cavity. The external hydraulic oil provides dynamic support force to the second sealing sleeve through the sliding cavity, so that it can automatically adjust its position with the slight radial displacement of the push rod during the push rod's jacking or retraction process, and maintain a tight fit with the push rod surface.

[0017] As a further embodiment of the sealing protective sleeve, the first sealing protective sleeve is also provided with an extension extending along the sliding cavity, and a compression cavity is provided between the extension and the second sealing protective sleeve. The instantaneous high-pressure environment formed by the compression cavity prevents external impurities from penetrating.

[0018] In this design, when the push rod moves, the hydraulic oil in the sliding cavity enters the compression cavity. As the second sealing sleeve slides along the sliding cavity, the volume change of the compression cavity generates a momentary high-pressure environment (the hydraulic oil pressure is higher than the external mud and water pressure). This high-pressure oil film can effectively prevent impurities such as mud, sand, and groundwater from seeping in through the gap between the extension and the second sealing sleeve.

[0019] As a further embodiment of the sealing protective sleeve, a sixth sealing ring is also provided between the extension and the second sealing protective sleeve.

[0020] In this design, the sixth sealing ring fits tightly against the contact surface of the extension and the second sealing sleeve, isolating the compression chamber from the external environment. This ensures that the high-pressure hydraulic oil in the compression chamber maintains a stable pressure, effectively preventing impurities such as mud, sand, and groundwater from seeping in, thus enhancing the sealing performance of the compression chamber as a high-pressure protective barrier. On the other hand, the elastic deformation characteristics of the sixth sealing ring itself allow it to be pushed back to its original position by elastic force after the second sealing sleeve slides along the sliding cavity.

[0021] As a further solution to the sealing protective sleeve, in order to effectively intercept trace amounts of leaked liquid or particulate impurities that may pass through the third sealing ring, a fifth sealing ring is provided between the second sealing protective sleeve and the push rod.

[0022] As a further embodiment of the sealing protective sleeve, the second sealing protective sleeve has a first channel in the middle that communicates with the sliding cavity, and a second channel is provided between the extension and the push rod. Both the first channel and the second channel communicate with the compression cavity.

[0023] In this scheme, when the hydraulic oil in the sliding cavity flows into the compression cavity through the first channel, the instantaneous high-pressure environment formed by the volume change in the compression cavity can push some of the hydraulic oil through the second channel to the area where the scraper ring and the second sealing ring are located, continuously providing lubrication for the contact surfaces of the scraper ring and the push rod, and the second sealing ring and the push rod, reducing frictional losses caused by mechanical movement. This active lubrication method can not only reduce the wear rate of the scraper ring and the second sealing ring, but also carry away the heat generated by friction through the flow of hydraulic oil, preventing the sealing components from failing due to high-temperature aging. At the same time, the high-pressure hydraulic oil further fills the sealing gap during the flow process, enhancing the anti-leakage capability of the sealing system.

[0024] In summary, compared with the prior art, this utility model has the following main advantages and beneficial effects:

[0025] 1. The double-layer structure of the first and second sealing protective sleeves in this utility model, combined with multiple sealing rings, significantly improves the pressure resistance and leakage resistance of the sealing system. It is especially suitable for complex working conditions such as water-rich sand layers and high water pressure, reducing the risk of failure of traditional single-layer seals.

[0026] 2. In this utility model, the paired scraper rings remove mud and sand particles in both directions when the push rod reciprocates, preventing hard particles from scratching the sealing ring; at the same time, the compression chamber guides hydraulic oil to circulate to the sealing area through the first channel and the second channel, actively lubricating the scraper ring and the second sealing ring, reducing friction loss and carrying away heat. Attached Figure Description

[0027] The accompanying drawings, which are included to provide a further understanding of the embodiments of the present invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0028] Figure 1 This is a schematic diagram of the structure of Embodiment 1 of the present utility model;

[0029] Figure 2 This is a schematic diagram of the structure of Embodiment 2 of the present invention;

[0030] Figure 3 for Figure 2 A magnified structural diagram of the structure marked A in the middle.

[0031] The attached diagram shows the markings and corresponding component names:

[0032] 1-Push rod, 2-Injection cylinder body, 3-First sealing protective sleeve, 4-Scraper ring, 5-First sealing ring, 6-Second sealing ring, 7-Second sealing protective sleeve, 8-Third sealing ring, 9-Fourth sealing ring, 10-Inlet / outlet oil port, 11-Fifth sealing ring, 12-First channel, 13-Sixth sealing ring, 14-Compression chamber, 15-Extension, 16-Second channel, 17-Sliding chamber. Detailed Implementation

[0033] To make the objectives, technical solutions, and advantages of this utility model clearer, the present utility model will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of this utility model are only used to explain this utility model and are not intended to limit this utility model.

[0034] Example 1

[0035] This embodiment 1 provides a sealing protective sleeve for the push rod of a pipe jacking machine, such as Figure 1 As shown, the sealing protective sleeve is installed between the jacking cylinder body 2 and the push rod 1;

[0036] Among them, such as Figure 1 As shown, the jacking cylinder body 2 serves as an external support structure, with an internal cavity for accommodating the push rod 1 and the sealing sleeve assembly. The push rod 1 achieves reciprocating jacking motion through the hydraulic drive of the jacking cylinder body 2 via the inlet and outlet oil ports 10. The sealing sleeve assembly includes a first sealing sleeve 3, with multiple first sealing rings 5 ​​arranged between the first sealing sleeve 3 and the inner wall of the jacking cylinder body 2, forming the first physical sealing barrier to prevent external mud and water from seeping in through the gap between the protective sleeve and the cylinder. Pairs of scraper rings 4 and two second sealing rings 6 are arranged sequentially between the first sealing sleeve 3 and the push rod 1 along the direction of movement. All second sealing rings 6 are located between the scraper rings 4. The paired scraper rings 4 and the second sealing rings 6 form a composite protective structure of "scraping-sealing-scraping". The scraper rings 4 can remove hard particles such as mud, sand, and gravel adhering to the surface of the push rod from both directions when the push rod 1 reciprocates, preventing particles from entering the sealing ring area with the movement of the push rod 1.

[0037] Meanwhile, the sealing protection sleeve assembly also includes a second sealing protection sleeve 7. A third sealing ring 8 is provided between the second sealing protection sleeve 7 and the inner wall surface of the jacking cylinder body 2 to further prevent mud and water from leaking from the outside of the first sealing protection sleeve 3, forming a second barrier. A fourth sealing ring 9 is provided between the second sealing protection sleeve 7 and the push rod 1. The fourth sealing ring 9 is a shaft Yxd sealing ring, which provides additional sealing protection.

[0038] Example 2

[0039] This embodiment 2 provides a sealing protective sleeve for the push rod of a pipe jacking machine, such as Figure 2 - As shown in Figure 3, the sealing protective sleeve is disposed between the jacking cylinder body 2 and the push rod 1;

[0040] Among them, such as Figure 2As shown, the jacking cylinder body 2 serves as an external support structure, with an internal cavity for accommodating the push rod 1 and the sealing sleeve assembly. The push rod 1 achieves reciprocating jacking motion through the hydraulic drive of the jacking cylinder body 2 via the inlet and outlet oil ports 10. The sealing sleeve assembly includes a first sealing sleeve 3, with multiple first sealing rings 5 ​​arranged between the first sealing sleeve 3 and the inner wall of the jacking cylinder body 2, forming the first physical sealing barrier to prevent external mud and water from seeping in through the gap between the protective sleeve and the cylinder. Pairs of scraper rings 4 and two second sealing rings 6 are arranged sequentially between the first sealing sleeve 3 and the push rod 1 along the direction of movement. All second sealing rings 6 are located between the scraper rings 4. The paired scraper rings 4 and the second sealing rings 6 form a composite protective structure of "scraping-sealing-scraping". The scraper rings 4 can remove hard particles such as mud, sand, and gravel adhering to the surface of the push rod from both directions when the push rod 1 reciprocates, preventing particles from entering the sealing ring area with the movement of the push rod 1.

[0041] Meanwhile, the sealing sleeve assembly also includes a second sealing sleeve 7. A sliding cavity 17 is provided between the push rod 1 and the jacking cylinder body 2. The sliding cavity 17 is connected to external hydraulic oil. The second sealing sleeve 7 can slide along the sliding cavity 17. The first sealing sleeve 3 is also provided with an extension 15 extending along the sliding cavity 17. Multiple third sealing rings 8 are provided between the extension 15 and the inner wall surface of the jacking cylinder body 2. A sixth sealing ring 13 is also provided between the extension 15 and the second sealing sleeve 7.

[0042] The gap between the sixth sealing ring 13, the extension 15, and the second sealing sleeve 7 forms a compression chamber 14. When the push rod 1 moves, the hydraulic oil in the sliding chamber 17 enters the compression chamber 14. As the second sealing sleeve 7 slides along the sliding chamber 17, the volume change of the compression chamber 14 generates an instantaneous high-pressure environment. This high-pressure oil film can effectively prevent impurities such as mud, sand, and groundwater from seeping in through the gap between the extension 15 and the second sealing sleeve 7. Furthermore, due to the elastic deformation characteristics of the sixth sealing ring 13 itself, it can push the second sealing sleeve 7 to reset through elastic force after it slides along the sliding chamber 17.

[0043] In some embodiments, in order to effectively intercept trace amounts of leaked liquid or particulate impurities that may pass through the third sealing ring 8, a fifth sealing ring 11 is provided between the second sealing protective sleeve and the push rod, serving as an auxiliary sealing unit.

[0044] In some embodiments, the second sealing sleeve 7 has a first channel 12 in the middle that communicates with the sliding cavity 17, and a second channel 16 is provided between the extension 15 and the push rod 1. Both the first channel 12 and the second channel 16 are connected to the compression cavity 14. When the hydraulic oil in the sliding cavity 17 flows into the compression cavity 14 through the first channel 12, the instantaneous high pressure environment formed by the volume change of the compression cavity 14 can push some of the hydraulic oil through the second channel 16 to the area where the scraper ring 4 and the second sealing ring 6 are located, continuously providing lubrication for the contact surfaces of the scraper ring 4 and the push rod 1, and the second sealing ring 6 and the push rod 1, reducing the frictional loss caused by mechanical movement. This active lubrication method can not only reduce the wear rate of the scraper ring 4 and the second sealing ring 6, but also carry away the heat generated by friction through the flow of hydraulic oil, avoiding the failure of the sealing components due to high temperature aging. At the same time, the high pressure hydraulic oil further fills the sealing gap during the flow process, enhancing the anti-leakage capability of the sealing system.

[0045] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of this utility model. It should be understood that the above description is only a specific embodiment of this utility model and is not intended to limit the scope of protection of this utility model. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this utility model should be included within the scope of protection of this utility model.

Claims

1. A sealing protective sleeve for a push rod of a pipe jacking machine, comprising a jacking cylinder body (2) and a push rod (1) built into the jacking cylinder body (2), characterized in that, A sealing protective sleeve assembly is provided between the push rod (1) and the jacking cylinder body (2); The sealing sleeve assembly includes a first sealing sleeve (3), a plurality of first sealing rings (5) are provided between the first sealing sleeve (3) and the inner wall surface of the jacking cylinder body (2), and a scraper ring (4) and a second sealing ring (6) are sequentially provided between the first sealing sleeve (3) and the push rod (1) along the movement direction.

2. The sealing protective sleeve for the push rod of a pipe jacking machine according to claim 1, characterized in that, The number of the second sealing rings (6) is at least two.

3. The sealing protective sleeve for the push rod of a pipe jacking machine according to claim 2, characterized in that, The scraper rings (4) are arranged in pairs, and all the second sealing rings (6) are located between the scraper rings (4).

4. The sealing protective sleeve for the push rod of a pipe jacking machine according to claim 3, characterized in that, The sealing sleeve assembly also includes a second sealing sleeve (7), at least one third sealing ring (8) is provided between the second sealing sleeve (7) and the inner wall surface of the jacking cylinder body (2), and at least one fourth sealing ring (9) is provided between the second sealing sleeve (7) and the push rod (1).

5. A sealing protective sleeve for a pipe jacking machine push rod according to claim 4, characterized in that, The fourth sealing ring (9) is a shaft Yxd sealing ring.

6. A sealing protective sleeve for a pipe jacking machine push rod according to any one of claims 1-3, characterized in that, The sealing protective sleeve assembly also includes a second sealing protective sleeve (7), and a sliding cavity (17) is provided between the push rod (1) and the jacking cylinder body (2), and the second sealing protective sleeve (7) can slide along the sliding cavity (17).

7. A sealing protective sleeve for a pipe jacking machine push rod according to claim 6, characterized in that, The first sealing sleeve (3) is also provided with an extension (15) extending along the sliding cavity (17), and a compression cavity (14) is provided between the extension (15) and the second sealing sleeve (7).

8. A sealing protective sleeve for a pipe jacking machine push rod according to claim 7, characterized in that, A sixth sealing ring (13) is also provided between the extension (15) and the second sealing protective sleeve (7).

9. A sealing protective sleeve for a pipe jacking machine push rod according to claim 8, characterized in that, A fifth sealing ring (11) is provided between the second sealing protective sleeve (7) and the push rod (1).

10. A sealing protective sleeve for a pipe jacking machine push rod according to claim 9, characterized in that, The second sealing protective sleeve (7) has a first channel (12) in the middle that communicates with the sliding cavity (17), and a second channel (16) is provided between the extension (15) and the push rod (1). Both the first channel (12) and the second channel (16) are in communication with the compression cavity (14).

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