Installation method of deepwater long-distance steel pipe fly line

Abstract

The invention provides an installation method of a deepwater long-distance steel pipe fly line, and relates to the technical field of fly line installation, and the installation method comprises the steps that the head end of the fly line is pulled out to pass through a tensioner and is connected with a balancing weight and a first buoyancy block; the balancing weight and the fly line end are hoisted and put into water, the crane and the fly line end rigging are connected on a deck, and the buoyancy block is pushed into water through a stern roller; the fly line is continuously and slowly lowered; the tail end of the fly wire is lifted out by a crane; the tail end of the fly line and the second buoyancy block are hoisted and put into water, and winch connection of the deck is removed; lowering until the balancing weight falls on the seabed; releasing a fly line and laying the fly line between the connecting unit and the Christmas tree; and connecting the fly wire between the connecting unit and the Christmas tree. The installation method can be suitable for installation of the fly line in the deepwater area, the twisting problem of the steel pipe fly line and the falling-off problem of the buoyancy block are reduced, the use frequency of a crane under the deepwater condition is reduced, and the fly line installation efficiency under the deepwater environment is improved.

Description

Technical Field

[0001] This invention relates to the field of fly-wire installation technology, and in particular to a method for installing long-distance steel pipe fly-wires in deep water. Background Technology

[0002] With the significant development of subsea production systems, flylines, as an indispensable component of complete subsea production systems, have been widely used. With the further development of some oil and gas fields, the water depth for flyline installation operations has gradually shifted from shallow water of 100-300 meters to deep water of over 1000 meters.

[0003] Currently, there are some common problems in the installation of fly lines in deep water, such as deformation and twisting of the fly line body, and detachment of buoyancy blocks. At the same time, the fly line designs of different manufacturers are also different, and the installation situation is complex and varied, requiring specific analysis for each situation. Summary of the Invention

[0004] The main technical problem to be solved by this invention is the deformation and twisting of the flying cable body and the detachment of the buoyancy block. In order to overcome the above-mentioned defects of the existing technology, a method for installing long-distance steel pipe flying cables in deep water is provided.

[0005] The technical solution adopted by this invention to solve its technical problem is: A method for installing long-distance steel pipe overhead lines in deep water includes the following steps: S1. On the workboat, pull the end of the fly line through the tensioner and connect it to the counterweight and the first buoyancy block; S2. Connect the crane to the bow end of the lowering rigging, lift and lower the counterweight and the bow end of the fly line into the water, disconnect the crane and the bow end of the fly line rigging on the deck, retrieve the crane, and push the first buoyancy block into the water from the stern roller. S3. The fly line is continuously and slowly lowered, and the turntable is used in conjunction with the tensioner to straighten it, eliminate deformation, and prevent twisting, until the end of the fly line is about to exit the fly line roller. S4. The crane lifts out the end of the fly wire, and the winch and the second buoyancy block are connected on the work vessel. S5. Lift the end of the flyline and the second buoyancy block and lower them into the water. Disconnect the winch from the deck. S6. Lower the counterweight until it lands on the seabed; S7. The work vessel moves and lowers the overhead wire to lay it between the connecting unit and the wellhead. The S8 and FLX tools are used to connect the fly wires between the connection unit and the wellhead.

[0006] Furthermore, in steps S2 and S3, deck personnel install an auxiliary monkey fist every five meters of cable.

[0007] Furthermore, in step S1, the end of the flying wire has an upper suspension point and a lower suspension point; Connect the counterweight to the lower lifting point, and connect the first buoyancy block to the upper lifting point; Step S1 includes: S1.1 On the work vessel, a crane is used to connect the ends of the fly line and pull the ends of the fly line from the fly line reel, while the turntable is used to release the cable. S1.2. The crane, in conjunction with the turntable, places the fly cable body into the tensioner, while the head end of the fly cable rests on the foam pad on the deck and temporarily secures the head end with a fastening strap. S1.3 Disconnect the crane from the head end; S1.4 Install the fly wire end bend limiter and auxiliary monkey fist sling, and connect the counterweight block and the first buoyancy block to the end of the fly wire respectively; S1.5 The crane lifts the counterweight block and places it in the middle of the water inlet bridge.

[0008] Furthermore, the water inlet bridge is moistened with water before step S2 to reduce friction during operation; Before step S2, connect the end of the fly wire to the turntable to prevent the tensioner from failing and the fly wire from slipping off; Step S2 includes: S2.1 The crane lifts the end of the fly line and slowly lowers the counterweight into the water, during which the crane, tensioner, and turntable work together to release the cable; S2.2 After the first end of the flying line and the counterweight block have been initially submerged in the water, the deck personnel disconnect the crane from the first end of the flying line and retrieve the crane. S2.3 The tensioner, in conjunction with the turntable, continuously releases the cable until the first buoyancy block rigging is taut; S2.4 The deck crew pushes the first buoyancy block into the water.

[0009] Furthermore, step S4 includes: S4.1 The turntable, in conjunction with the tensioner, releases the fly line and stops rotating before the end of the fly line detaches from the fly line reel. S4.2 The crane connects to the end of the fly line via a lifting sling, pulls the end of the fly line out of the fly line reel, and places it on the foam pad on the deck. Deck personnel install the bend limiter and auxiliary monkey fist sling. S4.3 Connect the lowering sling to the crane and the end of the fly line, and connect the other end of the fly line to the wire rope of the deck winch; S4.4 The crane, in conjunction with the winch, transfers the load, the tensioner slowly opens, and the crane, in conjunction with the winch, lifts the end of the fly wire to the front of the water inlet bridge; S4.5 The deck personnel connect the second buoyancy block to the end of the flyline.

[0010] Furthermore, in step S4.4, after the deck winch is fully loaded, the crane is loaded slightly more until the tensioner load is completely removed before the tensioner can be opened.

[0011] Furthermore, step S5 includes: S5.1 After the crane and the winch use the lowering sling and the winch connecting sling to lift the end of the flying line over the water inlet bridge, the crane swings back to the stern of the ship. S5.2 The deck personnel disconnect the winch from the end of the fly wire at the stern; S5.3 The crane slowly lowers the overhead line until the rigging of the second buoyancy block is taut; S5.4 The deck crew pushes the second buoyancy block down the stern roller; S5.5 The crane is swung to the outside of the ship's side and continues to lower.

[0012] Furthermore, in step S6, the first ROV observes the degree of twisting of the flying cable body; In step S7, the first ROV uses an auxiliary ROV to lay the overhead power line.

[0013] Furthermore, step S8 includes: S8.1 The second ROV, carrying an FLX tool, connects to the end of the flying wire, and the first ROV assists the second ROV in docking via an auxiliary sling; S8.2 After completing the connection between the FLX and the flying wire end, the second ROV drags the flying wire to the reconnection position for reconnection, and the first ROV assists the second ROV in reconnection by using an auxiliary lifting device. S8.3. Proceed to the first end of the flying wire and disconnect the counterweight block; S8.4 Repeat steps S8.1 and S8.2 to reconnect the first end.

[0014] Furthermore, it also includes the following steps: S9. Retrieve the counterweight, the first buoyancy block, and the second buoyancy block onto the deck of the work vessel.

[0015] The beneficial effects of this invention are: The present invention provides a method for installing large-size, long-distance steel pipe flylines using turntable tensioners and FLX reconnection. This method is applicable to the installation of large-size, long-distance steel pipe flylines using FLX tools for reconnection, and solves the problems of steel pipe flyline twisting and buoyancy block detachment, thereby improving flyline installation efficiency. Attached Figure Description

[0016] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0017] Figure 1 This is a simplified structural diagram of the present invention; Figure 2 This is a schematic diagram illustrating the process of first lifting the head end in this invention; Figure 3 This is a schematic diagram illustrating the process of secondly lifting the first end head in this invention; Figure 4 This is a schematic diagram illustrating the process of lowering the first end of the flying wire into the water in this invention. Figure 5 This is a schematic diagram of the process of the first suspension wire end in this invention; Figure 6 This is a schematic diagram of the process of the second suspension wire end in this invention; Figure 7 This is a schematic diagram illustrating the process of lowering the end of the flying wire into the water in this invention; Figure 8 This is a schematic diagram illustrating the process of lowering the first end of the flying line onto the seabed in this invention. Figure 9 This is a schematic diagram illustrating the process of lowering the end of the flying wire onto the seabed in this invention. Figure 10 This is a schematic diagram illustrating the process of connecting the second ROV to the flying wire end using the FLX360 tool in this invention; Figure 11 This is a schematic diagram illustrating the process by which the second ROV reconnects the fly wire end to the tree trunk in this invention.

[0018] Explanation of the labels in the diagram: 10-Flying line; 50-Foam pad; 11-Flying line head end; 12-Flying line tail end; 20-Counterweight block; 30-First buoyancy block; 40-Second buoyancy block; 100-Working vessel; 200-Flying line reel; 300-Inlet bridge; 360-Second ROV; 700-First ROV; 400-Turntable; 500-Tensioner; 600-Windlock; 900-Connecting unit; 1000-Tree of oil. Detailed Implementation

[0019] The present invention will be further described below with reference to specific embodiments. The illustrative embodiments and descriptions herein are used to explain the present invention, but are not intended to limit the present invention.

[0020] like Figure 1-11 As shown, this invention is based on a method for installing large-size, long-distance steel pipe flylines using a turntable with tensioners and FLX360 reconnection. It is suitable for laying and installing steel pipe flylines in deep-water environments. Specifically, this invention discloses a method for installing long-distance steel pipe flylines in deep water, which may include the following steps: First, the work vessel 100, carrying the 200 cable reel, is transported to the target sea area; then, a crane lowers the ROV (Remotely Operated Underwater Vehicle) tool basket onto the seabed. The ROV tool basket is used for retrieving cable pressure caps, as well as for placing emergency tools and garbage caps, etc. Continue with the deck arrangement before lowering the flyline 10; fix the water inlet bridge 300, turntable 400, and tensioner 500 and other installation auxiliary equipment, and place foam pads 50 on the deck near the water inlet bridge 300 for temporary placement of the flyline ends.

[0021] The first ROV 700 was launched into the water to observe the status of the wellhead 1000 and the connector of the connecting unit 900. The crane assisted the first ROV 700 in removing the pressure cap.

[0022] The flyline reel 200 is hoisted by a crane and connected to the turntable 400. A turntable 400 test is performed on the deck to ensure that the flyline 10 can exit the reel normally, and the flyline end 11 is adjusted to the correct route.

[0023] The specific steps are as follows: S1. On the work vessel 100, pull out the first end 11 of the fly line through the tensioner 500 and connect the counterweight block 20 and the first buoyancy block 30. like Figure 2 and Figure 3 As shown, step S1 further includes the following steps: S1.1 Connect the crane to the first end of the fly line 11 using temporary lifting slings, pull the first end of the fly line 11 out from the fly line reel 200, and slowly release the cable through the tensioner 500 with the help of the crane using the turntable 400. S1.2. Close the tensioner 500 and clamp the fly wire 10 cable body. The turntable 400, the crane, and the tensioner 500 can work together to repeatedly crush the cable body of the bend limiter section about 5 to 6 times to eliminate deformation. S1.3 Place the first end 11 of the flying wire on the foam pad 50, disconnect the crane connection, and temporarily fasten it with a fastening strap; S1.4 Deck personnel install the bend limiter of the flyline 10 and the underwater auxiliary sling, and connect the counterweight block 20 and the first buoyancy block 30 to the flyline head end 11; S1.5 The crane connects to the counterweight rigging and lifts the counterweight 20 to the middle position of the water inlet bridge 300; The flyline 10 has an upper suspension point and a lower suspension point at its flyline end 11. During connection, a counterweight is connected to the lower suspension point of the flyline end 11 via a counterweight rigging, and a first buoyancy block 30 is connected to the upper suspension point of the flyline end 11 via a buoyancy block rigging. Before step S2, wet the inlet bridge 300 with water to reduce friction of the fly line 10 as it passes over the inlet bridge 300, thus preventing damage to the fly line 10.

[0024] Before step S2, connect the end cap 12 of the flying wire and the turntable 400 to prevent the tensioner 500 from failing and the flying wire 10 from slipping. See details... Figure 5 and Figure 6 .

[0025] S2, such as Figure 4 As shown, the crane is connected to the lowering sling of the flyline head end, the counterweight block 20 and the flyline head end 11 are lifted and lowered into the water, the crane and flyline head end sling are disconnected on the deck, the crane is retrieved, and the first buoyancy block 30 is pushed into the water from the stern roller. This step S2 further includes the following steps. S2.1 The crane lifts the first end 11 of the launch line and slowly lowers the counterweight 20 into the water. During this time, the crane, tensioner 500, and turntable 400 work together to release the cable. After the flyline end 11 and counterweight 20 are initially submerged, the deck personnel disconnect the rigging between the crane and the flyline end 11 and retrieve the crane. S2.3, Tensioner 500 and turntable 400 continuously release the cable until the first buoyancy block 30 rigging is taut; S2.4 The deck crew pushes the first buoyancy block 30 into the water.

[0026] During the continuous cable laying process using the crane, tensioner 500, and turntable 400, an auxiliary "monkey fist" (a type of cable tie) needs to be attached to the cable every 5 meters after the bend limiter.

[0027] S3. The fly line is continuously and slowly lowered, and the turntable 400, in conjunction with the tensioner, straightens it to eliminate deformation and prevent twisting, until the end of the fly line 12 is about to be pulled out of the fly line reel 200.

[0028] S4, such as Figure 5 and Figure 6As shown, the crane lifts out the end 12 of the fly wire, and the connection of the winch 600 and the second buoy 40 is completed on the work vessel 100.

[0029] Specifically, refer to Figure 5 and Figure 6 Step S4 includes: S4.1, The turntable 400, in conjunction with the tensioner 500, releases the fly line and stops rotating before the end of the fly line is detached from the fly line reel 200; S4.2, such as Figure 5 As shown, the crane connects to the end 12 of the fly line via a lifting sling. After pulling the end 12 of the fly line out of the fly line reel 200, it is placed on the foam pad 50 on the deck. Deck personnel install the bend limiter and auxiliary monkey fist sling. S4.3, such as Figure 5 As shown, the end lowering sling is connected to the lifting lug below the end of the crane and the fly line end 12. The lowering lug of the fly line end 12 is also connected to the wire rope of the winch 600. At the same time, the connection between the turntable 400 and the fly line end 12 is released. S4.4, such as Figure 6 As shown, the crane, in conjunction with the winch 600, transfers the load to the winch 600 until the load on the tensioner 500 is 0. Then, the tensioner 500 slowly opens, and the crane, in conjunction with the winch 600, lifts the end 12 of the flying line to the front of the inlet bridge 300. S4.5, such as Figure 6 As shown, deck personnel connect the second buoyancy block 40 to the end 12 of the flyline.

[0030] S5. Lift the end of the flyline 12 and the second buoyancy block 40 and lower them into the water. Disconnect the winch from the deck.

[0031] refer to Figure 7 Step S5 specifically includes: S5.1, The crane and winch 600 use the lowering slings and winch connecting slings to lift the end 12 of the flying line over the water inlet bridge 300, and then the crane swings back to the stern of the ship; S5.2 Deck personnel shall disconnect the connection between winch 600 and the end of the flyline 12 at the stern. S5.3 The crane slowly lowers the flyline until the rigging is taut at the second buoyancy block 40. S5.4 The deck crew pushes the second buoyancy block 40 down the stern roller; S5.5. The crane is moved to the outside of the ship's side and the lowering continues.

[0032] S6, such as Figure 8As shown, the crane continues to lower the flyline until the flyline end 11 is connected to the counterweight 20 and lands on the seabed near the connecting unit 900.

[0033] During the deployment period, the first ROV700 observed the degree of twisting of the flying cable and the posture of the flying cable end 11 after the counterweight 20 was in place. S7, Combination Figure 8-9 The work vessel 100 moves toward the location of the tree 1000 and simultaneously lowers the flyline 10 and lays it between the connecting unit 900 and the tree 1000.

[0034] The first ROV 700 was used to observe the mud-contact point of the flyline 10 on the seabed underwater, and the laying route of the flyline 10 was adjusted by the auxiliary punches pre-tied to the cable body of the flyline 10.

[0035] When the flyline 10 is laid close to the side of the wellhead 1000, the ship stops and the condition of the flyline end 12 is observed underwater by the first ROV 700. If the flyline end 12 is in good condition, the subsequent flyline 10 reconnection operation is prepared.

[0036] S8, such as Figure 10-11 As shown, the second ROV 360 carries an FLX360 tool to connect the fly wire end, connecting the fly wire between the connection unit 900 and the wellhead 1000.

[0037] like Figure 10-11 As shown, step S8 includes: S8.1 The second ROV360, carrying the FLX360 tool, connects to the end of the flying wire, and the first ROV 700 assists the second ROV 360 in docking via an auxiliary sling; S8.2 After the FLX360 is connected to the end of the flying wire 12, the second ROV 360 drags the flying wire 10 to the oil well tree 1000 for reconnection, and the first ROV 700 assists the second ROV 360 in reconnection by auxiliary hoisting. S8.3 After completing the reconnection, the first ROV 700 goes to the first end of the flying wire 11 and disconnects the connection between the bottom lifting lug and the counterweight 20. S8.4 Repeat steps S8.1 and S8.2 to reconnect the first end of the flying wire 11.

[0038] S9. After the reconnection is completed, the crane lowers the recovery counterweight block 20, the first buoyancy block 30, and the second buoyancy block 40 to the deck of the work vessel 100, thus completing the installation of the entire flyline 10.

[0039] The present invention provides a method for installing large-size, long-distance steel pipe flylines using turntable tensioners and FLX reconnection. This method is applicable to flyline installation in deep water areas above 1000 meters, reducing problems such as steel pipe flyline twisting and buoyancy block detachment, reducing the number of times cranes are used in deep water conditions, and improving the efficiency of flyline installation in deep water environments.

[0040] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Any simple modifications, equivalent changes, and alterations made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A method of installing a long distance steel pipe flying lead in deep water, characterized in that, The method comprises the following steps: S1. on the workship, the flying line head end is pulled out of the tensioner, connected with the counterweight and the first buoyancy block; S2. the crane is connected with the flying line head end, the counterweight and the flying line head end are lowered into the water, the connection between the crane and the flying line head end is released on the deck, the crane is recovered, and the first buoyancy block is pushed into the water from the stern roller; S3. the flying line is continuously and slowly lowered, the turntable cooperates with the tensioner to straighten and eliminate deformation, and the flying line is prevented from being twisted until the end of the flying line is about to be out of the flying line roller; S4. the flying line end is lifted by the crane, and the winch and the second buoyancy block are connected on the workship; S5. the flying line end and the second buoyancy block are lifted and lowered into the water, and the winch connection is released on the deck; S6. lowering until the counterweight falls on the seabed; S7. the workship moves, and the flying line is lowered to be laid between the connection unit and the Christmas tree; S8. the FLX tool is connected to the flying line, and the flying line is connected between the connection unit and the Christmas tree.

2. The method of installing a long distance fly wire for a steel pipe in deep water according to claim 1, wherein In steps S2 and S3, the deck personnel install an auxiliary monkey fist every five meters of cable body.

3. The method of installing a long distance fly wire for a deep water steel pipeline according to claim 2, wherein In step S1, the end of the flying line has an upper lifting point and a lower lifting point; The counterweight is connected to the lower lifting point, and the first buoyancy block is connected to the upper lifting point; Step S1 comprises: S1.1, on the workship, the flying line head end is connected using the crane, the flying line head end is pulled out of the flying line cable reel, and the turntable cooperates with the cable during the process; S1.2, the crane cooperates with the turntable to place the flying line cable in the tensioner, and the flying line head end is placed on the foam pad on the deck, and the head end is temporarily fastened using a fastening belt; S1.3, disconnect the crane from the flying line head end; S1.4, install the flying line head end, the auxiliary monkey fist lifting belt, the counterweight and the first buoyancy block are connected with the flying line head end; S1.5, the crane lifts the counterweight to fall in the middle of the water bridge.

4. The method of installing a long distance fly wire for a deep water steel pipeline according to claim 3, wherein Before step S2, the water hose is used to wet the water bridge to reduce friction during the operation; Before step S2, the end of the flying line and the turntable are connected to prevent the tensioner from failing and the flying line from slipping; Step S2 comprises: S2.1, the crane lifts the flying line end and the counterweight slowly into the water, and the crane, the tensioner and the turntable cooperate with the cable during the process; S2.2, after the flying line head end and the counterweight are initially put into the water, the deck personnel release the connection between the crane and the flying line head end, and the crane is recovered; S2.3, the tensioner cooperates with the turntable to continuously release the cable until the first buoyancy block is straightened; S2.4, the deck personnel push the first buoyancy block into the water.

5. A method of installing a long distance fly wire for a deep water steel pipeline according to claim 4, wherein Step S4 comprises: S4.1, the turntable cooperates with the tensioner to release the flying line, and stops rotating before the flying line end is separated from the flying line cable reel. S4.2, the crane connects the flying line end head by the lifting cable, and the flying line end head is pulled out of the flying line cable reel and placed on the deck foam pad. The deck personnel install the bending limiter and auxiliary monkey fist sling; S4.3, the lowering cable is connected to the crane and the flying line end head. The other end of the flying line end head is connected to the steel wire rope of the deck winch; S4.4, the crane cooperates with the winch to transfer the load. The tensioner slowly opens, and the crane cooperates with the winch to lift the end flying line head before entering the water bridge; S4.5, the deck personnel connect the second buoyancy block to the flying line end head.

6. The method of installing a long distance fly wire for a deep water steel pipeline according to claim 5, wherein, In step S4.4, after the deck winch is fully loaded, the crane slightly loads, and until the tensioner load disappears completely, the tensioner can be opened.

7. The method of installing a long distance fly wire for a deep water steel pipeline according to claim 6, wherein Step S5 includes: S5.1, the crane and the winch cooperate with the lowering cable and the winch connection cable to lift the flying line end head over the water bridge, and then the crane is swung back to the stern; S5.2, the deck personnel remove the connection between the winch and the flying line end head at the stern; S5.3, the crane slowly lowers the flying line to the second buoyancy block cable; S5.4, the deck personnel push the second buoyancy block down the stern drum; S5.5, the crane is swung to the outside of the ship's side and continues to lower.

8. The method of installing a long distance fly wire for a deep water steel pipeline according to claim 7, wherein, In step S6, the first ROV observes the degree of twisting of the flying line cable body; In step S7, the first ROV lays the flying line with the assistance of the auxiliary monkey fist auxiliary work ship.

9. The method of installing a long distance fly wire for a deep water steel pipeline according to claim 8, wherein, Step S8 includes: S8.1, the second ROV carries the FLX tool to connect the flying line end head, and the first ROV assists the second ROV in docking through the auxiliary sling; S8.2, after the FLX and the flying line end head are connected, the second ROV drags the flying line to the back connection position for back connection, and the first ROV assists the second ROV in back connection through the auxiliary sling; S8.3, go to the flying line head end head, remove the counterweight connection; S8.4, repeat steps S8.1 and S8.2 to back connect the head end.

10. The method of installing a long distance fly wire for a deep water steel pipeline of claim 1, wherein, Further comprising the following steps: S9, the counterweight, the first buoyancy block and the second buoyancy block are recycled to the deck of the work ship.

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