Optical cable non-destructive crossing seal and method

Abstract

The present application relates to a kind of optical cable non-destructive crossing sealers and methods, comprising: sealing shell, using hollow structure;Front cone sleeve, be located in the hollow structure of sealing shell, and located in the front of sealing shell;Seal, at least two, located in the end of front cone sleeve, and spacer is arranged between adjacent seal;Cover, be located in the end of sealing shell, with the seal of being located in the last end is immediately adjacent, and spacer is also arranged between the seal and cover, by cover extruding each seal, between the optical cable of advance crossing and packer form high pressure seal.The present application can improve the construction efficiency of field, reduce optical cable loss, and improve optical cable service life.The present application can be applied in oil extraction field in oil field industry.

Description

Technical Field

[0001] This invention relates to the field of oilfield production technology, and in particular to a non-destructive fiber optic cable crossing seal and method. Background Technology

[0002] Currently, oilfields are undergoing digital transformation and upgrading. Digitalization of oilfields is an inevitable trend, using digital control to overcome the information asymmetry caused by time, space, and professional barriers between different fields and disciplines. Currently, intelligent mining and hydraulic mining require one or more cables / fiber optic cables to connect to the surface, transmitting signals to achieve downhole monitoring and digital unmanned control. Compared to cables, optical fibers are made of silicon dioxide, an inorganic material that can operate in extremely harsh environments, is more resistant to high temperatures and pressures, and has a longer lifespan and is less prone to damage downhole. However, currently, optical cables cannot be inserted seamlessly through packers, requiring cutting and splicing. Since optical cables are composed of multiple fiber bundles, and splicing each fiber has high environmental requirements and is technically challenging, repeated cutting and splicing are necessary if the communication requirements after splicing are not met, wasting considerable time. Prolonged downhole communication also leads to reliability issues at the splice due to high temperatures and pressures, and increased optical signal loss.

[0003] To ensure the proper passage of optical cables through the packer, most systems currently use an optical cable connector protector to protect the cables being connected. The basic procedure involves cutting the optical cable and, before lowering it into the well, passing both cables through the protector's ends. One cable passes through the packer, the outer sealing sleeve of the ferrule cap, the ferrule pin, and the connecting sleeve, exiting through the connecting sleeve. The other cable passes through the ferrule cap and the adapter, exiting through the adapter. During assembly, ferrules are inserted at both the front ferrule cap, the ferrule pin, the adapter, and the rear ferrule cap. The optical fibers in the two cables are then fused together, with the splice point positioned in the middle of the protected section. The optical cable connector protector is then sealed and fixed to the lowering string.

[0004] While this protector effectively protects the fiber optic connection points, on-site operations require a significant amount of time at the wellhead. A single fiber optic splice typically takes 7-8 hours, making on-site construction difficult and time-consuming. Multiple connections would require even longer periods. Furthermore, fiber optic cable splicing increases signal loss at the splice points, failing to address the fundamental issue of the inability to lower the entire cable without damage. Therefore, achieving seamless cable traversal, reducing time, and improving work efficiency have become urgent problems to be solved. Summary of the Invention

[0005] To address the aforementioned problems, the purpose of this invention is to provide a non-destructive optical cable crossing seal and method, which can improve on-site construction efficiency and extend the service life of optical cables.

[0006] To achieve the above objectives, the present invention adopts the following technical solution: a non-destructive optical cable crossing sealer, comprising: a sealing shell with a hollow structure; a front conical sleeve disposed within the hollow structure of the sealing shell and located at the front of the sealing shell; at least two sealing elements located at the end of the front conical sleeve, with gaskets provided between adjacent sealing elements; and a pressure cap disposed at the end of the sealing shell, adjacent to the last sealing element, with gaskets also provided between the sealing element and the pressure cap. By pressing the sealing elements with the pressure cap, a high-pressure seal is formed between the optical cable crossing the shell and the sealer.

[0007] Furthermore, the gland, front cone sleeve, seals, and gaskets all adopt a split structure.

[0008] Furthermore, the gland, front cone sleeve, seal, and gasket are all provided with through holes in the middle for the entire optical cable to pass through, and the through holes of each component are located on the same axis.

[0009] Furthermore, the front end of the sealed housing adopts a tapered structure.

[0010] Furthermore, the seals are made of hydrogenated nitrile rubber, polytetrafluoroethylene, or nitrile rubber elastic materials.

[0011] Furthermore, a threaded connection is used between the end of the gland and the sealing housing.

[0012] A method for non-destructive fiber optic cable crossing, based on the aforementioned non-destructive fiber optic cable crossing seal, includes: before entering the well, installing the non-destructive fiber optic cable crossing seal on the packer; after the installation of the non-destructive fiber optic cable crossing seal and the packer, inserting the entire fiber optic cable through the non-destructive fiber optic cable crossing seal into the packer; after the entire fiber optic cable is inserted, sequentially installing the split-structure front cone sleeve, seal, and gasket into the sealing housing, at which point the fiber optic cable is in a sliding state with no fixed connection to the packer and the non-destructive fiber optic cable crossing seal; after the packer is connected to the lower tubing at the wellhead, and the relative position of the fiber optic cable and the packer is determined, tightening the gland to seal and fix the fiber optic cable inside the packer, thus achieving non-destructive crossing of the entire fiber optic cable.

[0013] Furthermore, the optical cable undergoes multi-stage crossings, simultaneously passing through multiple packers.

[0014] The present invention has the following advantages due to the adoption of the above technical solutions:

[0015] The optical cable non-destructive crossing seal of this invention consists of a gland, a front conical sleeve, a sealing element, and a gasket. Each component adopts a split structure and is composed of two equally divided halves. The optical cable non-destructive crossing seal is installed on the packer. Through the cooperation between the split structure optical cable non-destructive crossing seal and the packer, the overall non-destructive crossing of the optical cable is achieved, which effectively improves the service life of the optical cable and the construction efficiency. Attached Figure Description

[0016] Figure 1 This is a cross-sectional view of the optical cable non-destructive crossing seal in an embodiment of the present invention;

[0017] Figure 2 This is a schematic diagram of the overall structure of the optical cable non-destructive crossing sealer in an embodiment of the present invention;

[0018] Figure 3 This is a schematic diagram of the sealing element structure in an embodiment of the present invention;

[0019] Figure 4 This is a schematic diagram of the gasket structure in an embodiment of the present invention;

[0020] Figure 5 This is a schematic diagram of the front conical sleeve structure in an embodiment of the present invention;

[0021] Figure 6 This is a schematic diagram of the installation of the optical cable non-destructive crossing sealer and packer in an embodiment of the present invention;

[0022] Figure 7 This is a schematic diagram of the optical cable being inserted entirely through the optical cable non-destructive penetration sealer and packer in an embodiment of the present invention;

[0023] Figure 8 yes Figure 7 A sectional view;

[0024] Figure 9 This is a schematic diagram of the installation of various components of the optical cable non-destructive crossing sealer in an embodiment of the present invention. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the described embodiments of the present invention are within the scope of protection of the present invention.

[0026] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the scope of exemplary embodiments according to the invention. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0027] To address the challenge of laying an entire optical cable, this invention provides a non-destructive optical cable crossing sealer and method, comprising: a sealing housing with a hollow structure; a front conical sleeve disposed within the hollow structure of the sealing housing and located at the front of the sealing housing; at least two sealing elements located at the ends of the front conical sleeve, with gaskets placed between adjacent sealing elements; and a pressure cap disposed at the end of the sealing housing, adjacent to the last sealing element, with a gasket also placed between the sealing element and the pressure cap. The pressure cap compresses the sealing elements, creating a high-pressure seal between the pre-laid optical cable and the sealer. This invention improves on-site construction efficiency, reduces optical cable loss, and extends the service life of the optical cable.

[0028] In one embodiment of the present invention, a non-destructive optical cable crossing seal is provided. In this embodiment, as... Figure 1 , Figure 2 As shown, the optical cable non-destructive crossing seal 1 includes:

[0029] The sealed housing 1.2 adopts a hollow structure;

[0030] The front cone sleeve 1.5 is disposed within the hollow structure of the sealing housing 1.2 and is located at the front of the sealing housing 1.2;

[0031] At least two seals 1.3 are provided at the end of the front cone sleeve 1.5, and a gasket 1.4 is provided between adjacent seals 1.3;

[0032] The pressure cap 1.1 is located at the end of the sealing housing 1.2 and is adjacent to the end sealing element 1.3. A gasket 1.4 is also provided between the sealing element 1.3 and the pressure cap 1.1. By pressing each sealing element 1.3 with the pressure cap 1.1, a high-pressure seal is formed between the optical cable and the packer.

[0033] In the above embodiments, such as Figures 3 to 5 As shown, the gland 1.1, front cone sleeve 1.5, seal 1.3, and gasket 1.4 all adopt a split structure, each consisting of two equally divided halves. The middle of the gland 1.1, front cone sleeve 1.5, seal 1.3, and gasket 1.4 are all provided with through holes for the entire optical cable to pass through. The through holes of each component are located on the same axis. In use, the split structure enables the entire optical cable to pass through.

[0034] In the above embodiments, the front end of the sealing housing 1.2 adopts a tapered structure to facilitate connection with the packer.

[0035] In the above embodiments, the sealing element 1.3 is made of elastic materials such as hydrogenated nitrile rubber, polytetrafluoroethylene, and nitrile rubber. This invention effectively improves the sealing pressure and achieves high reliability by using a sealing element 1.3 made of multi-grade rubber materials.

[0036] In the above embodiment, the end of the gland 1.1 and the sealing housing 1.2 are connected by threads. The gland 1.1... The connecting end is provided with an external thread, and the end of the sealing housing 1.2 is provided with an internal thread that mates with the external thread on the pressure cap 1.1.

[0037] In summary, during use, after the optical cable passes through, the front cone sleeve 1.5, the seal 1.3, and the gasket 1.4 are assembled into the housing in sequence (one seal 1.3 and one gasket 1.4 constitute a group). The sealing element 1.3 is squeezed by the threaded clamping force of the pressure cap 1.1 to ensure that a high-pressure seal is formed between the optical cable and the packer.

[0038] In one embodiment of the present invention, a method for non-destructive optical cable crossing is provided, which is implemented based on the non-destructive optical cable crossing sealer 1 described in the above embodiments. Specifically, in this embodiment, the method includes the following steps:

[0039] 1) Before entering the well, install the fiber optic cable non-destructive crossing sealer 1 on the packer 3, such as... Figure 6 As shown;

[0040] Specifically, such as Figure 6 As shown, the packer 3 has multiple channels for installing optical cables. The end of the packer 3 has a port that communicates with the channels. The optical cable passes through the front end of the packer 1 without damage and is installed in the corresponding port.

[0041] 2) After the fiber optic cable non-destructive passage sealer 1 and the packer 3 are installed, the entire fiber optic cable 2 is passed through the fiber optic cable non-destructive passage sealer 1 and into the packer 3, such as... Figure 7 , Figure 8 As shown;

[0042] 3) After the optical cable 2 is fully inserted, the split-structure front cone sleeve 1.5, seal 1.3 and gasket 1.4 are sequentially installed into the sealing housing 1.2. At this time, the optical cable 2 is in a sliding state with the packer 3 and the optical cable non-destructive passage sealer 1, without fixed connection. After the packer is connected to the lower tubing at the wellhead and the relative position of the optical cable and the packer is determined, the pressure cap 1.1 is tightened to seal and fix the optical cable 2 in the packer 3, thus realizing the non-destructive passage of the entire optical cable.

[0043] In step 3) above, the position between the optical cable 2 and the packer 3 can be adjusted on site.

[0044] In the above steps, the optical cable 2 can achieve multi-level crossing and pass through multiple packers 3 at the same time, with no limit on the number of levels.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A non-destructive optical cable crossing seal, characterized in that, include: The sealed housing has a hollow structure. The front cone sleeve is set inside the hollow structure of the sealing housing and is located at the front of the sealing housing; The seals are provided in at least two locations at the ends of the front cone sleeve, with gaskets between adjacent seals; The gland is located at the end of the sealing housing, adjacent to the endmost sealing element. A gasket is also provided between the sealing element and the gland. The gland compresses each sealing element, thereby creating a high-pressure seal between the pre-passed optical cable and the packer. The gland, front cone sleeve, seals and gaskets all adopt a split structure and are composed of two equally divided assemblies; The gland, front cone sleeve, seal, and gasket are all provided with through holes in the middle for the entire optical cable to pass through, and the through holes of each component are located on the same axis.

2. The optical cable non-destructive crossing seal as described in claim 1, characterized in that, The front end of the sealed housing adopts a tapered structure.

3. The optical cable non-destructive crossing seal as described in claim 1, characterized in that, The seals are made of hydrogenated nitrile rubber, polytetrafluoroethylene, or nitrile rubber elastic materials.

4. The optical cable non-destructive crossing seal as described in claim 1, characterized in that, The end of the gland and the sealing housing is connected by a thread.

5. A method for non-destructive optical cable crossing, characterized in that, This method is based on the non-destructive optical cable crossing seal as described in any one of claims 1 to 4, and includes: Before entering the well, the fiber optic cable non-destructive crossing sealer is pre-installed on the packer; After the fiber optic cable non-destructive passage sealer and packer are installed, the entire fiber optic cable is passed through the fiber optic cable non-destructive passage sealer into the packer; After the optical cable is fully inserted, the split-structure front cone sleeve, seals, and gaskets are sequentially installed into the sealing housing. At this time, the optical cable is in a sliding state with the packer and the optical cable non-destructive passage sealer, without fixed connection. After the packer is connected to the lower tubing at the wellhead and the relative position of the optical cable and the packer is determined, the gland is tightened to seal and fix the optical cable inside the packer, thus achieving non-destructive passage of the entire optical cable.

6. The non-destructive optical cable crossing method as described in claim 5, characterized in that, The optical cable traverses multiple levels, passing through multiple packers simultaneously.

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