A seal for the end of an optical cable within a tube

Abstract

The utility model discloses a kind of sleeve inner optical cable tail end sealing devices, the sleeve inner optical cable tail end sealing device includes sealing device body, optical cable body and sealing module;Sealing device body one end is inserted into the tail end of optical cable body, and the other end of sealing device body is connected with weak point module for preventing jam;Sealing module is provided with two and interval setting on sealing device body, and sealing module is set on optical cable body and forms sealing based on extrusion pressure.Two sealing units are oppositely arranged and form double sealing and realize main body sealing to optical cable body axial direction, realize multilayer sealing, improve the reliability of sealing.When the sleeve inner optical cable tail end sealing device is jammed, separation is realized by the fracture of weak point module, to protect optical cable body, do not cause optical cable loss.

Description

Technical Field

[0001] This utility model relates to the field of optical cable packaging technology, specifically to a sealing device for the tail end of an optical cable inside a sleeve. Background Technology

[0002] In oil and gas exploration, precise measurement of downhole formation parameters is required. Currently, one method used is to place optical cables inside casings and extend them deep into the well. However, in the high-temperature, high-pressure, and highly corrosive environment downhole, reliable sealing of the cable's tail end remains a challenge both domestically and internationally, making it difficult to achieve an effective seal.

[0003] Existing optical cable seals use conventional welding methods, which are difficult to guarantee reliable sealing. In actual engineering operations, water ingress at the cable's tail end is a frequent occurrence. Water ingress at the tail end causes significant changes to the cable's internal properties, ultimately rendering it unusable. Furthermore, during engineering operations, water ingress at the tail end can cause pressure to seep through the cable and onto the ground, potentially leading to serious safety incidents.

[0004] In addition, the tools for the end of the optical cable are generally composed of a sealing device and a counterweight. During the vertical seismic profiling operation of the optical cable inside the casing, when the tools for the end of the optical cable are lowered into high-risk well sections such as the open hole, they may get stuck and cause damage to the optical cable. Utility Model Content

[0005] The technical problem to be solved by this utility model is that the welding and sealing reliability of optical cables is poor during downhole oil and gas exploration; and the optical cables will be damaged if they get stuck during downhole operations. The purpose is to provide a sealing device for the tail end of the optical cable inside the casing to solve the above problems.

[0006] This utility model is achieved through the following technical solution:

[0007] A sealing device for the tail end of an optical cable inside a sheath includes a sealing device body, an optical cable body, and a sealing module.

[0008] One end of the sealing device body is inserted into the tail end of the optical cable body, and the other end of the sealing device body is connected to a weak point module for preventing jamming.

[0009] Two sealing modules are provided and spaced apart on the sealing device body. The sealing modules are sleeved on the optical cable body and form a seal based on the extrusion pressure.

[0010] In one possible design, the sealing device body includes a sealing cylinder, a sealing shaft, and a connecting cylinder connected sequentially from top to bottom;

[0011] Both the sealing cylinder and the connecting cylinder are constructed as cylindrical structures with one open end. Accordingly, the sealing cylinder is connected to the sealing shaft through its open end, and the other end of the sealing cylinder is connected to the weak point module; one end of the connecting cylinder is connected to the sealing shaft through its open end, and the other end of the connecting cylinder is equipped with an optical cable body protection module.

[0012] The first step hole and the second step hole are respectively provided at both ends of the sealing shaft, and the cavities inside the sealing cylinder and the connecting cylinder are respectively used as the first cavity and the second cavity;

[0013] Accordingly, the tail end of the optical cable body passes through the connecting tube and the sealing shaft and is inserted into the sealing tube.

[0014] In one possible design, the vulnerability module includes a vulnerability fastener, a vulnerability body, and a connector.

[0015] One end of the weak point fastener is connected to the sealing cylinder, and the other end is connected to the connector through the weak point body;

[0016] The weak point body is constructed as a rod-shaped structure, with one end connected to the weak point fixing component via a stepped shaft, and the other end connected to the connector via a thread.

[0017] The connector is used to connect tool strings;

[0018] Accordingly, when the pulling force on the optical cable body is greater than the tensile strength of the weak point body, the weak point body breaks, thereby separating the optical cable tail sealing device inside the sleeve from the tool string.

[0019] In one possible design, the optical cable body protection module includes an elastic element and a tapered sleeve unit sequentially sleeved on the optical cable body. The elastic element is used to control the swing range of the optical cable body, and the tapered sleeve unit is used to prevent the optical cable body from moving along its axial direction or rotating around its own axis.

[0020] In one possible design, a gooseneck spring is selected as the elastic element;

[0021] The tapered sleeve unit includes a large tapered sleeve, a middle tapered sleeve, and a small tapered sleeve, which are sequentially fitted from the outside to the inside. The outer wall of the large tapered sleeve is connected to the connecting cylinder by threads. A first gap is left between the large tapered sleeve and the middle tapered sleeve for clamping the outer armor of the optical cable body. A second gap is left between the middle tapered sleeve and the small tapered sleeve for clamping the inner armor of the optical cable body. The tapered sleeve unit also includes a limiting pin that passes through the connecting cylinder and is inserted into the large tapered sleeve, and at least one limiting pin is provided.

[0022] In one possible design, the sealing module includes a combined compression sealing unit located above and a pin-type sealing unit located below;

[0023] The sealing device body is provided with a first stepped hole and a second stepped hole arranged along its axial direction and opposite to each other, one of the stepped holes extending to the other stepped hole, and the inner diameter of the stepped hole gradually decreasing to the outer diameter of the optical cable body;

[0024] Correspondingly, the tail end of the optical cable passes through two stepped holes;

[0025] Accordingly, the combined extrusion sealing unit and the pin-type sealing unit are respectively inserted into the two stepped holes and used to press against the stepped holes to form a seal.

[0026] In one possible design, the combined compression sealing unit includes a first elastic bushing, a first rigid pressure ring, a compression pad, and a compression screw;

[0027] A plurality of first elastic bushings and first rigid pressure rings are provided, and the two are spaced apart in the first small hole of the first stepped hole;

[0028] The clamping pad is placed in the first central hole of the first stepped hole and abuts against the outermost first elastic bushing;

[0029] The clamping screw is positioned in the first large hole of the first stepped hole and abuts against the clamping pad;

[0030] Accordingly, the first stepped hole includes a first small hole, a first medium hole and a first large hole connected in sequence; the sealing device body is provided with a first cavity located outside the first stepped hole, through which the clamping screw is screwed;

[0031] Accordingly, tightening screws are turned and pressure pads are moved to control the pressure pads against or release the first elastic bushing, thereby controlling the pressure of the first elastic bushing against the first stepped hole.

[0032] In one possible design, the pin-type sealing unit includes a second elastic bushing, a second rigid pressure ring, a sealing plug, and a sealing sleeve;

[0033] The second elastic bushing and the second rigid pressure ring are provided in several units, and they are spaced apart in the second small hole of the second stepped hole;

[0034] One end of the sealing plug is inserted into the second small hole of the second stepped hole and abuts against the outermost second elastic bushing; the other end of the sealing plug extends to the outside of the second stepped hole and connects to the sealing sleeve.

[0035] One end of the sealing sleeve is elastic, and this end extends out of the sealing plug and is fitted onto the optical cable body.

[0036] Correspondingly, the sealing device body has a second cavity located outside the second step hole, and one end of the sealing plug and the sealing sleeve are both located in the second cavity;

[0037] Accordingly, when there is a pressure difference in the second cavity, the sealing sleeve is compressed and transmits the pressure to the second elastic bushing, so that the second elastic bushing is compressed and deformed and presses against the second stepped hole.

[0038] In one possible design, the sealing plug is threaded to the second stepped hole, and a sealing ring is provided between the sealing plug and the second stepped hole;

[0039] The sealing sleeve is made of elastic material and includes a large-diameter portion fitted on the sealing plug and a small-diameter portion fitted on the optical cable body. The sealing plug has an annular protrusion for connecting the large-diameter portion.

[0040] In one possible design, the end of the optical cable body is provided with a sealing sleeve and an adhesive layer for filling the gap between the two.

[0041] Compared with the prior art, this utility model has the following advantages and beneficial effects:

[0042] 1. Two sealing units are arranged opposite each other to form a double seal and achieve a main body seal in the axial direction of the optical cable body, realizing multi-layer sealing and improving the reliability of the seal.

[0043] 2. When the sealing device at the end of the optical cable inside the sleeve is stuck, separation is achieved by breaking the weak point module to protect the optical cable body and prevent optical cable loss.

[0044] 3. The tail end of the optical cable body is sealed by a sealing sleeve. When the sealing sleeve is under external pressure, it deforms under the pressure difference and plays a sealing role. The greater the external pressure, the greater the degree of deformation and the better the sealing effect. Attached Figure Description

[0045] 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:

[0046] Figure 1 This is a schematic diagram of a sealing device for the end of an optical cable inside a sheath.

[0047] Figures 2-4 They are respectively Figure 1 A magnified schematic diagram of the three parts: left, center, and right.

[0048] Figure 5 for Figure 1 A magnified schematic diagram of the structure at point IV.

[0049] Figure 6 for Figure 1 A magnified schematic diagram of the structure at point II.

[0050] Figure 7 for Figure 1 A magnified schematic diagram of the structure at point I.

[0051] The attached diagram shows the markings and corresponding component names:

[0052] 100. Sealing device body; 200. Optical cable body; 1. Sealing cylinder; 2. Sealing shaft; 3. Connecting cylinder; 4. Combined compression sealing unit; 401. First elastic bushing; 402. First rigid pressure ring; 403. Pressure pad; 404. Pressure screw; 5. Pin-type sealing unit; 501. Second elastic bushing; 502. Second rigid pressure ring; 503. Sealing plug; 504. Sealing sleeve; 6. Weak point module; 601. Weak point fixing component; 602. Weak point body; 603. Connector; 7. Tool string; 8. Elastic component; 9. Conical sleeve unit; 901. Large conical sleeve; 902. Medium conical sleeve; 903. Small conical sleeve; 10. Sealing rubber sleeve. Detailed Implementation

[0053] 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.

[0054] Example:

[0055] like Figures 1-7 As shown, a sealing device for the tail end of an optical cable inside a sheath includes a sealing device body 100, an optical cable body 200, and a sealing module.

[0056] One end of the sealing device body 100 is inserted into the tail end of the optical cable body 200, and the other end of the sealing device body 100 is connected to a weak point module 6 for anti-jamming.

[0057] Two sealing modules are provided and spaced apart on the sealing device body 100. The sealing modules are sleeved on the optical cable body 200 and form a seal based on the extrusion pressure.

[0058] In the casing-in-the-canopy optical cable end sealing device, two sealing units cooperate with each other and serve as backups, increasing the number of sealing structures and achieving multi-layer sealing, thereby improving the reliability of the seal. Meanwhile, during downhole exploration, the casing-in-the-canopy optical cable end sealing device may become stuck. Forcibly pulling it in this situation could easily damage the optical cable body 200. Therefore, a weak point module 6 is installed on the sealing cylinder 1, and separation is achieved through the breakage of the weak point module 6, thus protecting the optical cable body 200.

[0059] During operation, workers pre-select the required model of the optical cable body 200 and install it into the corresponding sealing device body 100. Then, using existing equipment, the optical cable end sealing device is lowered into the well, allowing the optical cable body 200 to be lowered for exploration work. If the optical cable end sealing device gets stuck during downhole operations, the optical cable body 200 is pulled upwards to disconnect the weak point module.

[0060] In one possible implementation, the sealing device body 100 includes a sealing cylinder 1, a sealing shaft 2, and a connecting cylinder 3 connected sequentially from top to bottom;

[0061] Both the sealing cylinder 1 and the connecting cylinder 3 are constructed as cylindrical structures with one open end. Accordingly, the sealing cylinder 1 is connected to the sealing shaft 2 through its open end, and the other end of the sealing cylinder 1 is connected to the weak point module 6; one end of the connecting cylinder 3 is connected to the sealing shaft 2 through its open end, and the other end of the connecting cylinder 3 is provided with an optical cable body protection module.

[0062] The first step hole and the second step hole are respectively provided at both ends of the sealing shaft 2, and the cavities inside the sealing cylinder 1 and the connecting cylinder 3 are respectively used as the first cavity and the second cavity;

[0063] Accordingly, the tail end of the optical cable body 200 passes through the connecting tube 3 and the sealing shaft 2 and is inserted into the sealing tube 1.

[0064] Based on the above design, a first cavity and a second cavity are formed by two cylindrical structures, a sealing cylinder 1 and a connecting cylinder 3, to facilitate adjustment of the sealing unit after the optical cable end sealing device is formed inside the sleeve. The two sealing units are respectively located at both ends of the sealing shaft 2, forming a double seal and achieving a main body seal in the axial direction of the optical cable body 200. The end of the connecting cylinder 3 away from the sealing shaft 2 has a chamfer, which serves to guide and reduce friction.

[0065] In addition, during the downhole exploration process, if the optical cable body 200 shakes or rotates, or is subjected to unexpected disturbances, it will affect the exploration results and easily damage the optical cable body 200. Therefore, an optical cable body protection module is installed on the connecting cylinder 3 to reduce or even eliminate unexpected disturbances to the optical cable body 200.

[0066] Specifically, alternatively, such as Figure 3 and Figure 4 As shown, the weak point module 6 includes a weak point fastener 601, a weak point body 602, and a connector 603;

[0067] One end of the weak point fixing member 601 is connected to the sealing cylinder 1, and the other end is connected to the connector 603 through the weak point body 602;

[0068] The weak point body 602 is constructed as a rod-shaped structure, with one end connected to the weak point fixing member 601 via a stepped shaft, and the other end connected to the connector 603 via a thread.

[0069] Connector 603 is used to connect tool string 7;

[0070] Accordingly, when the pulling force on the optical cable body 200 is greater than the tensile strength of the weak point body 602, the weak point body 602 breaks, thereby separating the optical cable tail sealing device inside the sleeve from the tool string 7.

[0071] Based on the above design, the weak point fixing component 601 and the connector 603 cooperate with each other to connect the fiber optic cable tail sealing device inside the casing with the tool string 7. The two are also connected through the weak point body 602. Specifically, when the weak point body 602 is not broken, the fiber optic cable tail sealing device inside the casing is connected to the tool string 7, so that the fiber optic cable tail sealing device inside the casing can move downhole and realize exploration. Conversely, when the fiber optic cable tail sealing device inside the casing gets stuck during downhole operation, the fiber optic cable body 200 is pulled upward until the pulling force is greater than the tensile strength of the weak point body 602. The weak point body 602 will break, causing the fiber optic cable tail sealing device inside the casing to separate from the tool string 7, thereby releasing the fiber optic cable body 200 and protecting the fiber optic cable body 200.

[0072] It's easy to understand that tool string 7 can be a heavy hammer or any other suitable existing part, offering a wide range of choices and good practicality.

[0073] Furthermore, considering the tensile strength of the optical cable, the weak point body 602 is preferably made of high-strength, high-toughness special alloy structural steel. By changing the size of the weak point body 602, weak point bodies 602 with different tensile strength values ​​are available to meet the requirements of optical cable logging. In addition, to prevent corrosion by well fluid, the surface of the weak point body 602 is coated according to the anti-corrosion grade requirements.

[0074] For the weak body 602, in order to prevent the threads between the weak body 602 and the connector 603 from slipping, a limit screw is provided in the longitudinal direction of the weak body 602 to restrict the movement of the weak body 602 in the axial direction and ensure the reliability of the weak body 602.

[0075] For the weak point fixing part 601, it can be threaded to the sealing cylinder 1, and the thread is provided with anti-slip groove and fixing screw to prevent slippage. The connection stability between the weak point fixing part 601 and the sealing cylinder 1 is improved by the cooperation of these two.

[0076] Specifically, alternatively, such as Figure 2 and Figure 7 As shown, the optical cable body protection module includes an elastic element 8 and a conical sleeve unit 9 sequentially sleeved on the optical cable body 200. The elastic element 8 is used to control the swing range of the optical cable body 200, and the conical sleeve unit 9 is used to prevent the optical cable body 200 from moving along its axial direction or rotating around its own axis.

[0077] Based on the above design, the elastic element 8 provides elastic force. When the optical cable body 200 swings, the elastic force controls the swing range of the optical cable body 200 within a safe range, preventing excessive bending and damage to the optical cable body 200. The tapered sleeve unit 9 restricts the optical cable body 200 from moving along its axial direction or rotating around its own axis. The two elements work together to limit the degrees of freedom of the optical cable body 200, ensuring that any unexpected disturbances to the optical cable body 200 during downhole operations are within acceptable limits.

[0078] Optionally, the elastic element 8 can be a gooseneck spring. Based on this, the gooseneck spring can be fitted onto the optical cable body 200, with its two ends connected to the optical cable body 200 and the connecting cylinder 3, respectively. It is readily understood that the elastic element 8 can also be any other suitable existing spring.

[0079] Optionally, the tapered sleeve unit 9 includes a large tapered sleeve 901, a middle tapered sleeve 902, and a small tapered sleeve 903, which are sequentially fitted from the outside to the inside. The outer wall of the large tapered sleeve 901 is threaded to the connecting cylinder 3. A first gap is left between the large tapered sleeve 901 and the middle tapered sleeve 902 for clamping the outer armor of the optical cable body 200. A second gap is left between the middle tapered sleeve 902 and the small tapered sleeve 903 for clamping the inner armor of the optical cable body 200. The tapered sleeve unit 9 also includes a limiting pin that passes through the connecting cylinder 3 and is inserted into the large tapered sleeve 901, and at least one limiting pin is provided.

[0080] Based on this, when the optical cable body 200 passes through the conical sleeve unit 9, the optical cable body 200 successively peels off the outer armor and inner armor, and then respectively inserts the armor sheath into the gap between two adjacent conical sleeves, realizing the connection between the optical cable body 200 and the conical sleeve unit 9. Furthermore, a limiting pin is provided between the large conical sleeve 901 and the connecting cylinder 3, which restricts the degree of freedom of the conical sleeve unit 9 and the optical cable body 200, preventing the optical cable body 200 from moving along its axial direction or rotating around its own axis.

[0081] In one possible implementation, the sealing module includes an upper combined compression sealing unit 4 and a lower pin-type sealing unit 5;

[0082] The sealing device body 100 is provided with a first stepped hole and a second stepped hole arranged along its axial direction and opposite to each other, one of the stepped holes extending to the other stepped hole, and the inner diameter of the stepped hole gradually decreasing to the outer diameter of the optical cable body 200.

[0083] Correspondingly, the tail end of the optical cable body 200 passes through two stepped holes;

[0084] Accordingly, the combined compression sealing unit 4 and the pin-type sealing unit 5 are respectively inserted into the two stepped holes and used to press against the stepped holes to form a seal.

[0085] Based on the above design scheme, the sealing unit is inserted into the stepped hole, that is, the sealing unit is located between the sealing device body 100 and the optical cable body 200, realizing the connection and sealing of the sealing device body 100 and the optical cable body 200. Moreover, one of the stepped holes extends to the other stepped hole and the inner diameter gradually decreases, making the space at the opposite end of the two sealing units more narrow, resulting in better squeezing effect and better sealing performance under external pressure.

[0086] The combined extrusion sealing unit 4 achieves sealing by extrusion pressure, and the greater the extrusion pressure, the better the sealing effect. The extrusion pressure can be flexibly adjusted according to the actual working conditions to better adapt to the actual working conditions.

[0087] The pin-type sealing unit 5 has good reliability and can be used to prevent water and air leakage, making it suitable for a wider range of applications. The pin-type sealing unit 5 also has an anti-misinsertion design, making assembly simpler and faster.

[0088] In addition, two sealing units are arranged along the axial direction of the sealing device body 100 to achieve multi-layer sealing of the optical cable body 200.

[0089] Specifically, alternatively, such as Figure 3 and Figure 5 As shown, the combined compression sealing unit 4 includes a first elastic bushing 401, a first rigid pressure ring 402, a compression pad 403, and a compression screw 404;

[0090] A plurality of first elastic bushings 401 and first rigid pressure rings 402 are provided, and the two are spaced apart in the first small hole of the first stepped hole;

[0091] The clamping pad 403 is disposed in the first central hole of the first stepped hole and abuts against the outermost first elastic bushing 401;

[0092] The clamping screw 404 is disposed in the first large hole of the first stepped hole and abuts against the clamping pad 403;

[0093] Accordingly, the first stepped hole includes a first small hole, a first medium hole and a first large hole connected in sequence; the sealing device body 100 is provided with a first cavity located outside the first stepped hole, and the clamping screw 404 is tightened through the first cavity;

[0094] Accordingly, tightening screw 404 is turned and pressure pad 403 is driven to move, so as to control pressure pad 403 to press against or release first elastic bushing 401, so as to control the pressure of first elastic bushing 401 against first stepped hole.

[0095] Based on the above design, tightening the clamping screw 404 applies force actively. This force is transmitted through the clamping pad 403 to the first small hole in the first stepped hole, causing the first elastic bushing 401 to be compressed and deformed. The first elastic bearing fills the gap and provides a seal. Multiple first elastic bushings 401 achieve multi-layer sealing, which helps improve the reliability of the seal. Simultaneously, a first rigid pressure ring 402 is provided between two adjacent first elastic bushings 401, utilizing the rigidity of the first rigid pressure ring 402 for support. Furthermore, the force applied by the clamping screw 404 can be actively controlled by the operator, allowing for adjustments based on actual working conditions to ensure that the seal of the combined compression sealing unit 4 is adapted to the actual working conditions.

[0096] It is easy to understand that, if necessary, such as when the working conditions change, the staff can also loosen the 404 clamping screws appropriately.

[0097] It is worth noting that a chamfer is provided at the diameter change point of the first-step hole. By dispersing stress and eliminating stress concentration, the fatigue strength and long-term reliability of the parts are significantly improved. The chamfering process also removes burrs, making the edges smoother, avoiding scratches to operators or mating parts, and acts as a guide during assembly, facilitating the smooth entry of shaft-type parts.

[0098] Accordingly, a first cavity is provided on the sealing device body 100 to provide space for workers to process the first stepped hole and complete the installation of the combined extrusion sealing unit 4.

[0099] Optionally, such as Figure 2 and Figure 6 As shown, the pin-type sealing unit 5 includes a second elastic bushing 501, a second rigid pressure ring 502, a sealing plug 503, and a sealing sleeve 504;

[0100] The second elastic bushing 501 and the second rigid pressure ring 502 are provided in several units, and the two are spaced apart in the second small hole of the second stepped hole;

[0101] One end of the sealing plug 503 is inserted into the second small hole of the second stepped hole and abuts against the outermost second elastic bushing 501; the other end of the sealing plug 503 extends to the outside of the second stepped hole and connects to the sealing sleeve 504.

[0102] One end of the sealing sleeve 504 is elastic, and this end extends to the outside of the sealing plug 503 and is sleeved on the optical cable body 200.

[0103] Correspondingly, the sealing device body 100 is provided with a second cavity located outside the second step hole, and one end of the sealing plug 503 and the sealing sleeve 504 are both located in the second cavity;

[0104] Accordingly, when there is a pressure difference in the second cavity, the sealing sleeve 504 is compressed and transmits the pressure to the second elastic bushing 501, so that the second elastic bushing 501 is compressed and deformed and presses against the second stepped hole.

[0105] Based on the above design, the combination of the second elastic bushing 501 and the second rigid pressure ring 502 has the same function as the combination of the first elastic bushing 401 and the first rigid pressure ring 402, and will not be described again here. The sealing plug 503 acts as a grouting screw, which is used to apply force and deform the second elastic bushing 501 so that the second elastic bushing 501 can perform a sealing function.

[0106] The elastic end of the sealing sleeve 504 can sense external pressure. If the external pressure increases, the sealing sleeve 504 will be deformed by the external pressure so that the sealing sleeve 504 can play a sealing role. Moreover, the greater the external pressure, the greater the degree of deformation of the sealing sleeve 504 and the better the sealing effect.

[0107] Correspondingly, a chamfer is provided at the diameter change of the second step hole; a second cavity is provided on the sealing device body 100 to provide space for workers to process the second step hole and complete the installation of the combined pin-type sealing unit 5.

[0108] Based on this, the combined extrusion sealing unit 4 and the pin-type sealing unit 5 are similar in structure and principle, which helps to reduce the economic costs of design, production, and manufacturing. However, there are also differences between the two. In actual use, when the sealing device body 100 enters the well, the pin-type sealing unit 5 is below and the combined extrusion sealing unit 4 is above. Therefore, the pin-type sealing unit 5 is equipped with an elastic sealing sleeve 504, which uses the external pressure difference to further eliminate gaps and improve the sealing effect.

[0109] Optionally, the sealing plug 503 is threadedly connected to the second stepped hole, and a sealing ring is provided between the sealing plug 503 and the second stepped hole. Based on this, the deformation degree of the second elastic sleeve 501 is controlled by screwing the sealing plug 503, thereby controlling the sealing effect of the second elastic sleeve 501. The sealing ring is used to fill the tiny gaps between the threads, helping to improve the sealing performance.

[0110] Optionally, the sealing sleeve 504 is made of an elastic material, and includes a large-diameter portion fitted onto the sealing plug 503 and a small-diameter portion fitted onto the optical cable body 200. The sealing plug 503 has an annular protrusion for connecting the large-diameter portion. Based on this, the sealing sleeve 504 as a whole can sense external pressure, and thus deform under pressure to achieve a seal, which helps to improve the sealing effect of the pin-type sealing unit 5.

[0111] In one possible implementation, the end of the optical cable body 200 is provided with a sealing sleeve 10 and an adhesive layer for filling the gap between the two.

[0112] Based on the above design, the sealing sleeve 10 has a certain degree of elasticity, which can deform under pressure difference and seal the tail end of the optical cable body 200. The greater the pressure difference, the better the sealing effect. At the same time, considering that there is a gap between the sealing sleeve 10 and the optical cable body 200, glue is injected to fill the gap, further improving the sealing effect.

[0113] 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 device for the tail end of an optical cable inside a sheath, characterized in that, It includes a sealing device body (100), an optical cable body (200), and a sealing module; One end of the sealing device body (100) is inserted into the tail end of the optical cable body (200), and the other end of the sealing device body (100) is connected to a weak point module (6) for anti-jamming. Two sealing modules are provided and spaced apart on the sealing device body (100). The sealing modules are sleeved on the optical cable body (200) and form a seal based on the extrusion pressure.

2. The sealing device for the end of an optical cable inside a sleeve according to claim 1, characterized in that, The sealing device body (100) includes a sealing cylinder (1), a sealing shaft (2) and a connecting cylinder (3) connected in sequence from top to bottom; Both the sealing cylinder (1) and the connecting cylinder (3) are constructed as cylindrical structures with one open end. Accordingly, the sealing cylinder (1) is connected to the sealing shaft (2) through its open end, and the other end of the sealing cylinder (1) is connected to the weak point module (6); one end of the connecting cylinder (3) is connected to the sealing shaft (2) through its open end, and the other end of the connecting cylinder (3) is provided with an optical cable body protection module. The first step hole and the second step hole are respectively set at both ends of the sealing shaft (2), and the cavities inside the sealing cylinder (1) and the connecting cylinder (3) are respectively used as the first cavity and the second cavity; Accordingly, the tail end of the optical cable body (200) passes through the connecting tube (3) and the sealing shaft (2) and is inserted into the sealing tube (1).

3. The sealing device for the end of an optical cable inside a sleeve according to claim 2, characterized in that, The weak module (6) includes a weak fastener (601), a weak body (602), and a connector (603); One end of the weak point fastener (601) is connected to the sealing cylinder (1), and the other end is connected to the connector (603) through the weak point body (602). The weak point body (602) is constructed as a rod-shaped structure, with one end connected to the weak point fixing member (601) via a stepped shaft, and the other end connected to the connector (603) via a thread. The connector (603) is used to connect the tool string (7); Accordingly, when the pulling force on the optical cable body (200) is greater than the tensile strength of the weak point body (602), the weak point body (602) breaks, so that the optical cable end sealing device in the sleeve is separated from the tool string (7).

4. The sealing device for the end of an optical cable inside a sleeve according to claim 2, characterized in that, The optical cable body protection module includes an elastic element (8) and a cone sleeve unit (9) sequentially sleeved on the optical cable body (200). The elastic element (8) is used to control the swing range of the optical cable body (200), and the cone sleeve unit (9) is used to prevent the optical cable body (200) from moving along its axis or rotating around its own axis.

5. The sealing device for the end of an optical cable inside a sleeve according to claim 4, characterized in that, The elastic element (8) is a gooseneck spring; The conical sleeve unit (9) includes a large conical sleeve (901), a middle conical sleeve (902) and a small conical sleeve (903) arranged sequentially from the outside to the inside. The outer wall of the large conical sleeve (901) is connected to the connecting cylinder (3) by threads. A first gap is left between the large conical sleeve (901) and the middle conical sleeve (902) for clamping the outer armor of the optical cable body (200). A second gap is left between the middle conical sleeve (902) and the small conical sleeve (903) for clamping the inner armor of the optical cable body (200). The conical sleeve unit (9) also includes a limiting pin that passes through the connecting cylinder (3) and is inserted into the large conical sleeve (901), and at least one limiting pin is provided.

6. The sealing device for the end of an optical cable inside a sheath according to claim 1, characterized in that, The sealing module includes a combined compression sealing unit (4) located above and a pin-type sealing unit (5) located below. The sealing device body (100) is provided with a first stepped hole and a second stepped hole arranged along its axial direction and opposite to each other, one of the stepped holes extending to the other stepped hole, and the inner diameter of the stepped hole gradually decreasing to the outer diameter of the optical cable body (200); Accordingly, the tail end of the optical cable body (200) passes through two stepped holes; Accordingly, the combined compression sealing unit (4) and the pin-type sealing unit (5) are respectively inserted into the two stepped holes and used to press against the stepped holes to form a seal.

7. The sealing device for the end of an optical cable inside a sheath according to claim 6, characterized in that, The combined compression sealing unit (4) includes a first elastic bushing (401), a first rigid pressure ring (402), a pressure pad (403), and a pressure screw (404). A plurality of first elastic bushings (401) and first rigid pressure rings (402) are provided, and the two are spaced apart in the first small hole of the first stepped hole; The clamping pad (403) is disposed in the first central hole of the first stepped hole and abuts against the outermost first elastic bushing (401). The clamping screw (404) is set in the first large hole of the first step hole and abuts against the clamping pad (403). Accordingly, the first stepped hole includes a first small hole, a first medium hole and a first large hole connected in sequence; the sealing device body (100) is provided with a first cavity located outside the first stepped hole, and the clamping screw (404) is screwed through the first cavity. Accordingly, tightening screws (404) are turned and pressure pads (403) are moved to control pressure pads (403) against or release the first elastic bushing (401) to control the pressure of the first elastic bushing (401) against the first stepped hole.

8. The sealing device for the end of an optical cable inside a sheath according to claim 6, characterized in that, The pin-type sealing unit (5) includes a second elastic bushing (501), a second rigid pressure ring (502), a sealing plug (503), and a sealing sleeve (504). The second elastic bushing (501) and the second rigid pressure ring (502) are provided in several units, and the two are spaced apart in the second small hole of the second stepped hole; One end of the sealing plug (503) is inserted into the second small hole of the second step hole and abuts against the outermost second elastic bushing (501), and the other end of the sealing plug (503) extends to the outside of the second step hole and connects to the sealing sleeve (504). One end of the sealing sleeve (504) is elastic, and the other end extends out of the sealing plug (503) and is fitted onto the optical cable body (200); Correspondingly, the sealing device body (100) is provided with a second cavity located outside the second step hole, and one end of the sealing plug (503) and the sealing sleeve (504) are both located in the second cavity; Accordingly, when there is a pressure difference in the second cavity, the sealing sleeve (504) is compressed and transmits pressure to the second elastic bushing (501), so that the second elastic bushing (501) is compressed and deformed and presses against the second stepped hole.

9. The sealing device for the end of an optical cable inside a sheath according to claim 8, characterized in that, The sealing plug (503) is threaded to the second stepped hole, and a sealing ring is provided between the sealing plug (503) and the second stepped hole; The sealing sleeve (504) is made of elastic material and includes a large diameter portion fitted on the sealing plug (503) and a small diameter portion fitted on the optical cable body (200). The sealing plug (503) is provided with an annular protrusion for connecting the large diameter portion.

10. The sealing device for the end of an optical cable inside a sleeve according to any one of claims 1-9, characterized in that, The end of the optical cable body (200) is provided with a sealing sleeve (10) and an adhesive layer for filling the gap between the two.

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