A method for connecting a broken optical cable in an umbilical cable of an offshore oil well

Abstract

The present invention discloses a method for splicing a broken optical cable in an offshore oil well umbilical cable, comprising the following steps: splicing a steel pipe, repairing an inner sheath, splicing a steel wire, and repairing an outer sheath; dividing the broken optical cable into a first optical cable and a second optical cable; sequentially performing optical fiber fusion splicing of the first optical cable and the second optical cable, splicing the steel pipe, repairing the inner sheath, splicing the steel wire, and repairing the outer sheath; and trimming the outer sheath to ensure the roundness and uniformity of the outer diameter of the repaired portion. Through the above-described method, the method for splicing a broken optical cable in an offshore oil well umbilical cable of the present invention can splice the broken optical cable during the production process of the offshore oil well umbilical cable, ensuring the structural stability and performance of the spliced ​​optical cable.

Description

Technical Field

[0001] The present invention relates to the field of marine oil well umbilical cables, in particular to a method for connecting a broken optical cable in a marine oil well umbilical cable. Background Art

[0002] Marine oil well umbilical cable is an integrated cable system used to connect marine oil well platforms with underwater production systems and other equipment. It is usually composed of cables (power cables or signal cables), optical cables (single-mode or multi-mode optical cables), hydraulic or chemical pipes (steel pipes or hoses), and also includes isolation supports, armor layers, reinforcement belts, sheaths and other structures, which are relatively complex.

[0003] Long umbilical cables can reach thousands of meters in length, requiring high stability during processing, but they are still prone to breakage. During the production of offshore oil well umbilical cables, if a cable breaks, it is usually impossible to reconnect it, forcing the entire umbilical cable to be scrapped, resulting in significant cost losses and the need for improvement. Summary of the Invention

[0004] The main technical problem solved by the present invention is to provide a method for splicing broken optical cables in marine oil well umbilical cables, which can splice optical cables during the production process and reduce the risks and cost losses in the production process of marine oil well umbilical cables.

[0005] In order to solve the above technical problems, the present invention adopts a technical solution: providing a method for connecting a broken optical cable in an offshore oil well umbilical cable, comprising the following steps:

[0006] a. Connection of steel pipes:

[0007] dividing the broken optical cable into a first optical cable and a second optical cable;

[0008] Remove J meters of outer sheath from the broken ends of the first and second optical cables to expose the inner armor wires, and cut off K meters of optical units respectively;

[0009] Fix the optical unit of the first optical cable horizontally on the fixed frame, and fix the optical unit of the second optical cable horizontally on the movable frame in front of the fixed frame, and clamp them with a clamp (if necessary, use sandpaper or dust-free paper to pad the clamp to prevent the inner tube from slipping when inserting the optical unit, causing damage to the optical fiber);

[0010] At a position where the first optical cable is L meters away from the optical unit port, the steel tube in the optical unit is removed to expose the optical fiber; at a position where the second optical cable is M meters away from the optical unit port, the steel tube in the optical unit is removed to expose the optical fiber;

[0011] Insert one end of the inner cannula into the steel tube in the first optical cable, pass the exposed optical fiber of the first optical cable through the inner cannula, straighten each optical fiber, measure the first and second optical cables, retain N meters of exposed optical fiber, cut off the excess optical fiber, use a fusion splicer to fusion-splice the corresponding optical fibers in the first and second optical cables to achieve optical fiber splicing, and test both ends of the connected optical fibers. If the test fails, cut the optical fiber and perform the optical unit processing and fusion splicing operation again;

[0012] After the optical fiber test is qualified, apply the fiber paste evenly to the surface of the optical fiber to make the optical fiber into strands;

[0013] Move the optical unit in the second optical cable forward by using the moving frame to straighten the optical fiber, then lower the other end of the inner tube and insert it into the steel tube in the second optical cable. Use a steel tube crimping die and crimping pliers to crimp the steel tube and the inner tube.

[0014] b. Repair of inner sheath:

[0015] Wrapping the exposed outer wall of the inner tube with insulating tape to form an insulating filling sleeve, and making the outer diameter of the insulating filling sleeve correspond to the outer diameter of the inner sheath;

[0016] Use the reserved thermoplastic tube to repair the inner sheath. First, chamfer the ends of the inner sheaths on the first and second optical cables to form a cone angle. Then, overlap the thermoplastic tube and the cone angle. Heat the thermoplastic tube with a hot air gun to shrink it and fit tightly against the steel pipe and insulating filling sleeve. Use sandpaper to polish the overlap position.

[0017] c. Wire connection:

[0018] Winding the inner armor steel wires on the first optical cable and the second optical cable onto the repaired inner sheath and the thermoplastic tube according to the inner armor pitch;

[0019] The inner armor steel wires on the first optical cable are butted against the inner armor steel wires on the second optical cable one by one to form a plurality of butt joints, and the ends of the butted inner armor steel wires are cut so that the butt joints are spaced apart along the axial direction of the inner sheath, and then the inner armor steel wires are fastened and fixed in sections with copper wires;

[0020] Use wirelock glue to butt-fix the two inner armor steel wires at the butt joint;

[0021] Apply wirelock glue to the outside of the inner armor wire and wait for the glue to solidify completely;

[0022] d. Repair of outer sheath:

[0023] Defective portions of the outer sheaths of the first and second optical cables are removed, and the outer sheath ends are cut into stress cone structures, followed by grinding and cleaning.

[0024] Use polyethylene tape to tightly wrap layers around the inner armor steel wire and the outer sheath at both ends, overlap the stress cone structure, and obtain a polyethylene tape wrap. The diameter of the polyethylene tape wrap is 2~3mm larger than the diameter of the outer sheath, and the end of the polyethylene tape wrap overlaps the end of the outer sheath by 30~40mm.

[0025] Wrap the polytetrafluoroethylene tape over the outer surface of the polyethylene tape wrapping body, and extend the wrapping to more than 50mm above the outer sheaths at both ends. Secure the two ends of the polytetrafluoroethylene tape with paper tape to form a polytetrafluoroethylene tape layer;

[0026] Wrap the glass ribbon tightly around the outer surface of the polytetrafluoroethylene tape layer to form a glass ribbon layer, and tie both ends of the glass ribbon firmly with paper tape;

[0027] Wrap the copper tape tightly around the outer surface of the glass ribbon layer, and secure the two ends of the copper tape with paper tape to prevent it from loosening;

[0028] Use a blowtorch to bake the copper tape. During the baking process, the blowtorch flame moves back and forth within the repair range where the polyethylene tape is wrapped around the package to ensure that the repair position is evenly heated.

[0029] After baking, immediately cool the surface of the copper tape with a wet cloth and wrap the polyethylene tape around the package to shape it;

[0030] After the surface temperature of the copper tape drops to a safe temperature, the cooling operation can be stopped. The wrapped copper tape, glass ribbon, and polytetrafluoroethylene tape can be removed in sequence. The inside of the repaired part of the polyethylene tape wrapping can be observed to see if there is poor plasticization or other defects. If visible delamination is observed in the repaired part, the above baking steps need to be repeated.

[0031] The outer sheath is trimmed to ensure the roundness and uniformity of the outer diameter of the repaired part.

[0032] In a preferred embodiment of the present invention, J is greater than K.

[0033] In a preferred embodiment of the present invention, the overlap rate of the polytetrafluoroethylene tape on the outer surface of the polyethylene tape wrapped around the outer surface of the package is above 50%.

[0034] In a preferred embodiment of the present invention, the glass ribbon is completely covered with a polytetrafluoroethylene tape layer.

[0035] In a preferred embodiment of the present invention, the copper tape completely covers the glass ribbon layer.

[0036] In a preferred embodiment of the present invention, the interval between the docking points is 30 cm.

[0037] In a preferred embodiment of the present invention, the thermoplastic tube is pre-sheathed on the optical unit of the first optical cable or the second optical cable before the steel tube is connected.

[0038] The beneficial effects of the present invention are as follows: the method for splicing a broken optical cable in an offshore oil well umbilical cable provided by the present invention can splice the broken optical cable during the production process of the offshore oil well umbilical cable, thereby ensuring the structural stability and performance of the optical cable after splicing, and reducing the risks and cost losses of the offshore oil well umbilical cable during the production process. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for describing the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. Those skilled in the art can also derive other drawings based on these drawings without inventive work, among which:

[0040] Figure 1 It is a structural schematic diagram of a preferred embodiment of a steel pipe splicing step in a method for splicing a broken optical cable in an offshore oil well umbilical cable according to the present invention;

[0041] Figure 2 It is a structural schematic diagram of a preferred embodiment of a steel wire splicing step in a method for splicing a broken optical cable in an offshore oil well umbilical cable according to the present invention;

[0042] Figure 3 It is a structural schematic diagram of a preferred embodiment of a step of repairing an outer sheath in a method for connecting a broken optical cable in an offshore oil well umbilical cable according to the present invention. DETAILED DESCRIPTION

[0043] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0044] like Figure 1 As shown, the optical cable in the marine oil well umbilical cable comprises an optical fiber 11, a steel pipe 12, an inner sheath 13, an inner armored steel wire 14 and an outer sheath 15 from the inside to the outside, and needs to be spliced ​​and repaired step by step from the inside to the outside.

[0045] See also Figures 1 to 3 , embodiments of the present invention include:

[0046] A method for connecting a broken optical cable in an offshore oil well umbilical cable comprises the following steps:

[0047] a. Connection of steel pipes:

[0048] Divide the broken optical cable into a first optical cable 1 and a second optical cable 2;

[0049] Remove 4 meters of outer sheath 15 from the broken ends of the first optical cable 1 and the second optical cable 2 to expose the inner armor steel wire 14, and cut 2 meters of each optical unit (the optical unit includes the optical fiber 11, the steel tube 12 and the inner sheath 13);

[0050] Sleeving the thermoplastic tube onto the optical unit of the first optical cable or the second optical cable;

[0051] Fix the optical unit of the first optical cable 1 horizontally on the fixed frame, and fix the optical unit of the second optical cable 2 horizontally on the movable frame in front of the fixed frame. Clamp them with a clamp. To prevent the optical unit from slipping during the insertion of the inner tube, pad the clamp with sandpaper or dust-free paper to avoid damage to the optical fiber caused by slipping of the optical unit.

[0052] At the position of the first optical cable 0.5m away from the optical unit port, use a fine file to file a circle of scratches on the steel pipe along the circumference (requirement: to facilitate breaking the steel pipe and not damage the optical fiber), then gently bend it up and down and left and right by hand to break it and slowly pull it out (requirement: during the withdrawal process, the pipe opening should not damage the optical fiber). At the position of 0.9m away from the remaining steel pipe end, use a blade to cut a circle of scratches on the steel pipe along the circumference (requirement: to facilitate breaking the steel pipe and not damage the optical fiber), then gently bend it up and down and left and right by hand to break it and slowly pull it out (requirement: during the withdrawal process, the pipe opening should not damage the optical fiber), so that about 1.4m of optical fiber is exposed at one end of the fixed frame;

[0053] At the position of the second optical cable 0.5 meters from the optical unit port, use a fine file to score the steel pipe along the circumference. Then, use your hands to gently bend it up and down and left and right to break it and slowly pull it out. At the position of 0.4 meters from the remaining steel pipe end, use a blade to cut the steel pipe along the circumference. Then, use your hands to gently bend it up and down and left and right to break it and slowly pull it out, leaving about 0.9 meters of optical fiber exposed at one end of the mobile frame. Clean the optical fiber with a dust-free cloth and retain the clean fiber paste for subsequent use.

[0054] The method for removing the steel tube is to use a fine file to scratch the steel tube along the circumference (requirement: to facilitate breaking the steel tube and not damage the optical fiber), then gently bend it up and down and left and right by hand to break it and slowly pull it out (requirement: during the extraction process, the tube mouth should not damage the optical fiber);

[0055] Insert one end of the inner cannula into the steel tube in the first optical cable, pass the exposed optical fiber of the first optical cable through the inner cannula, straighten each optical fiber, measure the first and second optical cables, retain N meters of exposed optical fiber, cut off the excess optical fiber, use a fusion splicer to fusion-splice the corresponding optical fibers in the first and second optical cables to achieve optical fiber splicing, and test both ends of the connected optical fibers. If the test fails, cut the optical fiber and perform the optical unit processing and fusion splicing operation again;

[0056] After the optical fiber test is qualified, apply the fiber paste evenly to the surface of the optical fiber to make the optical fiber into strands;

[0057] Move the optical unit in the second optical cable forward by using the moving frame to straighten the optical fiber, then lower the other end of the inner tube and insert it into the steel tube in the second optical cable. Use a steel tube crimping die and crimping pliers to crimp the steel tube and the inner tube.

[0058] b. Repair of inner sheath:

[0059] Wrapping the exposed outer wall of the inner tube with insulating tape to form an insulating filling sleeve, and making the outer diameter of the insulating filling sleeve correspond to the outer diameter of the inner sheath;

[0060] Use the reserved thermoplastic tube to repair the inner sheath. First, chamfer the ends of the inner sheaths on the first and second optical cables to form a cone angle. Then, overlap the thermoplastic tube and the cone angle. Heat the thermoplastic tube with a hot air gun to shrink it and fit tightly against the steel pipe and insulating filling sleeve. Use sandpaper to polish the overlap position.

[0061] c. Wire connection:

[0062] Winding the inner armor steel wires on the first optical cable and the second optical cable onto the repaired inner sheath and the thermoplastic tube according to the inner armor pitch;

[0063] Connect the inner armor wires on the first optical cable to the inner armor wires on the second optical cable one by one. Figure 2 As shown, a plurality of docking points 15 are formed, and the ends of the inner armor wires to be docked are cut so that the docking points are spaced apart along the axial direction of the inner sheath. In this embodiment, the axial interval between two adjacent docking points is 30 cm, forming 6 to 8 docking points. The inner armor wires are then fastened and fixed in sections with copper wire.

[0064] Use wirelock glue to butt-fix the two inner armor steel wires at the butt joint;

[0065] Wirelock glue is applied to the outer side of the inner armor wire and the glue is completely solidified to improve the reliability of the inner armor wire connection and achieve uniform force when pulled.

[0066] In this embodiment, the wirelock glue can be the WIRELOCK® series product produced by Millfield Enterprises (Manufacturing) Limited of the United Kingdom. Wirelock glue was previously mainly used for casting knots of metal ropes. In this application, it can improve the reliability of the inner armor steel wire joints.

[0067] d. Repair of outer sheath:

[0068] The outer sheath defects of the first optical cable and the second optical cable are removed, and the outer sheath ends are cut into a stress cone structure 16, such as Figure 3 As shown, perform grinding and cleaning;

[0069] Polyethylene tape is tightly wound layer by layer onto the inner armor steel wire and the outer sheaths at both ends, overlapping the stress cone structure 16 to obtain a polyethylene tape wrapping body. The diameter of the polyethylene tape wrapping body is 2-3 mm larger than the diameter of the outer sheath, and the end of the polyethylene tape wrapping body overlaps the end of the outer sheath by 30-40 mm.

[0070] The polytetrafluoroethylene tape is overlapped and wrapped around the outer surface of the polyethylene tape wrapping body, and is extended to wrap over the outer sheaths at both ends by more than 50 mm. The ends of the polytetrafluoroethylene tape are firmly fixed with paper tape to form a polytetrafluoroethylene tape layer. In this embodiment, the overlap rate of the polytetrafluoroethylene tape on the outer surface of the polyethylene tape wrapping body is more than 50%, which facilitates subsequent disassembly and avoids the problem of adhesion between the polyethylene tape wrapping body and the polytetrafluoroethylene tape.

[0071] Wrap the glass ribbon tightly around the outer surface of the polytetrafluoroethylene tape layer to form a glass ribbon layer. Tie both ends of the glass ribbon firmly with paper tape to prevent it from loosening. The glass ribbon completely covers the polytetrafluoroethylene tape layer, which has a good thermal conductivity.

[0072] The copper tape is tightly wrapped around the outer surface of the glass ribbon layer. The two ends of the copper tape are firmly fixed with paper tape to prevent it from loosening. The copper tape completely covers the glass ribbon layer to ensure thermal conductivity and uniform heating of the glass ribbon layer. The polytetrafluoroethylene tape is then heated through the glass ribbon layer to perform hot melt forming of the polyethylene tape wrapping body.

[0073] Use a blowtorch to bake the copper tape. During the baking process, the blowtorch flame moves back and forth within the repair range where the polyethylene tape is wrapped around the package to ensure that the repair position is evenly heated.

[0074] After baking, immediately cool the surface of the copper tape with a wet cloth and wrap the polyethylene tape around the package to shape it;

[0075] After the surface temperature of the copper tape drops to a safe temperature, the cooling operation can be stopped. The wrapped copper tape, glass ribbon, and polytetrafluoroethylene tape can be removed in sequence. The inside of the repaired part of the polyethylene tape wrapping can be observed to see if there is poor plasticization or other defects. If visible delamination is observed in the repaired part, the above baking steps need to be repeated.

[0076] The outer sheath is trimmed to ensure the roundness and uniformity of the outer diameter of the repaired part.

[0077] In summary, the present invention provides a method for splicing a broken optical cable in an offshore oil well umbilical cable, which realizes the splicing of the broken optical cable, ensures the stability and reliability of the structure after splicing, meets the production of long-length offshore oil well umbilical cables, and reduces the loss caused by optical cable breakage.

[0078] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A method for splicing a broken optical cable in an offshore oil well umbilical cable, which is used to splice a broken optical cable during production, characterized in that: The following steps are involved: a. Connection of steel pipes: dividing the broken optical cable into a first optical cable and a second optical cable; Remove J meters of outer sheath from the broken ends of the first and second optical cables to expose the inner armor wires, and cut off K meters of optical units respectively; Fix the optical unit of the first optical cable horizontally on the fixed frame, and fix the optical unit of the second optical cable horizontally on the movable frame in front of the fixed frame; At a position where the first optical cable is L meters away from the optical unit port, the steel tube in the optical unit is removed to expose the optical fiber; at a position where the second optical cable is M meters away from the optical unit port, the steel tube in the optical unit is removed to expose the optical fiber; Insert one end of the inner cannula into the steel tube in the first optical cable, pass the exposed optical fiber of the first optical cable through the inner cannula, straighten each optical fiber, measure the first and second optical cables, retain N meters of exposed optical fiber, cut off the excess optical fiber, use a fusion splicer to fusion-splice the corresponding optical fibers in the first and second optical cables to achieve optical fiber splicing, and test both ends of the spliced ​​optical fibers; Move the optical unit in the second optical cable forward by using the moving frame to straighten the optical fiber, then lower the other end of the inner tube and insert it into the steel tube in the second optical cable. Use a steel tube crimping die and crimping pliers to crimp the steel tube and the inner tube. b. Repair of inner sheath: Wrapping the exposed outer wall of the inner tube with insulating tape to form an insulating filling sleeve, and making the outer diameter of the insulating filling sleeve correspond to the outer diameter of the inner sheath; Use the reserved thermoplastic tube to repair the inner sheath. First, chamfer the ends of the inner sheaths on the first and second optical cables to form a cone angle. Then, overlap the thermoplastic tube and the cone angle. Heat the thermoplastic tube with a hot air gun to shrink it and fit tightly against the steel pipe and the insulating filling sleeve. c. Wire connection: Winding the inner armor steel wires on the first optical cable and the second optical cable onto the repaired inner sheath and the thermoplastic tube according to the inner armor pitch; The inner armor steel wires on the first optical cable are butted against the inner armor steel wires on the second optical cable one by one to form a plurality of butt joints, and the ends of the butted inner armor steel wires are cut so that the butt joints are spaced apart along the axial direction of the inner sheath, and then the inner armor steel wires are fastened and fixed in sections; Use wirelock glue to butt-fix the two inner armor steel wires at the butt joint; Apply wirelock glue to the outside of the inner armor wire and wait for the glue to solidify completely; d. Repair of outer sheath: Defective portions of the outer sheaths of the first and second optical cables are removed, and the outer sheath ends are cut into stress cone structures, followed by grinding and cleaning. Use polyethylene tape to tightly wrap layers around the inner armor steel wire and the outer sheath at both ends, overlap the stress cone structure, and obtain a polyethylene tape wrap. The diameter of the polyethylene tape wrap is 2~3mm larger than the diameter of the outer sheath, and the end of the polyethylene tape wrap overlaps the end of the outer sheath by 30~40mm. Wrap the polytetrafluoroethylene tape over the outer surface of the polyethylene tape wrapping body, and extend the wrapping to more than 50mm on the outer sheaths at both ends to form a polytetrafluoroethylene tape layer; The glass ribbon is tightly wrapped around the outer surface of the polytetrafluoroethylene tape layer to form a glass ribbon layer; Wrap the copper tape tightly around the outer surface of the glass ribbon layer; Use a blowtorch to bake the copper tape. During the baking process, the blowtorch flame moves back and forth within the repair range where the polyethylene tape is wrapped around the package to ensure that the repair position is evenly heated. After baking, immediately cool the surface of the copper tape with a wet cloth and wrap the polyethylene tape around the package to shape it; Remove the wrapped copper tape, glass ribbon, and polytetrafluoroethylene tape in sequence; The outer sheath is trimmed to ensure the roundness and uniformity of the outer diameter of the repaired part.

2. The method for connecting a broken optical cable in an offshore oil well umbilical cable according to claim 1, characterized in that: Said J is greater than K.

3. The method for connecting a broken optical cable in an offshore oil well umbilical cable according to claim 1, characterized in that: The overlapping rate of the polytetrafluoroethylene tape on the outer surface of the polyethylene tape wrapped around the outer surface of the package is above 50%.

4. The method for connecting a broken optical cable in an offshore oil well umbilical cable according to claim 1, characterized in that: The glass ribbon is completely covered with a polytetrafluoroethylene tape layer.

5. The method for connecting a broken optical cable in an offshore oil well umbilical cable according to claim 1, characterized in that: The copper tape completely covers the glass ribbon layer.

6. The method for connecting a broken optical cable in an offshore oil well umbilical cable according to claim 1, characterized in that: The interval between the docking points is 30 cm.

7. The method for connecting a broken optical cable in an offshore oil well umbilical cable according to claim 1, characterized in that: The thermoplastic tube is pre-sheathed on the optical unit of the first optical cable or the second optical cable before the steel tube is connected.

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