Apparatus and method for recovering flexible pipe without using a dedicated ship

Abstract

The present invention relates to a device for the recovery of flexible pipes without the use of a dedicated ship, which uses resources with low cost and does not have the obligation of not damaging the device during the handling of the flexible pipes, since the device is suitable for pipes at the end of their useful life or that have already been damaged. These types of pipes are an important responsibility for some operators in the oil industry. The techniques used for the use in the abandonment phase of the oil field or even for the recovery of pipes that do not have any prospect of use use ships with minimum adaptability, which include the presence of recovery / laying wheels with much smaller diameter than the wheels used on conventional ships, or, alternatively, they include the launching of a dedicated recovery reel, with its own drive, to allow the winding of the scrap pipe at the launch point, followed by the recovery assembly and its transfer to the ship itself.

Description

Technical Field

[0001] This invention relates to a device for collecting flexible pipes without the use of a dedicated vessel, used in the oil exploration and production sector, primarily on ships, platforms, drilling rigs, and production facilities, designed to use lower-cost resources, and which, due to the non-reusable nature of these pipes, does not aim to damage them during handling. Background Technology

[0002] Typically, naval resources used in the dropping and collection of submarine flexible pipelines are very expensive and have low availability. A common resource (1) for both reused and discarded pipelines is the PLSV (Pipeline Supply Vessel), a highly sought-after resource that can be dedicated solely to value-added activities such as pipeline installation or relocation. Collecting pipelines with diminished service life is part of a commitment made to environmental agencies when applying for installation and operation permits, which is why these pipelines are not simply discarded in place. Due to the responsibility for handling discarded pipelines awaiting collection, whether because of structural damage to the pipeline, because the pipeline has reached the end of its operational service life, or because the pipeline does not possess the characteristics required for a new project, there is a need to use low-cost resources that do not guarantee against damage to such equipment during disposal.

[0003] Document AU2014397727B2 relates to a method for installing and removing flexible pipelines deployed between an offshore platform and a subsea structure positioned beneath the platform, such that relative movement between the structures disconnects the connection. The method includes an intermediate step of supporting the pipeline from the platform itself, followed by dropping the pipeline and interconnecting it with appropriate subsea equipment. The system utilizes winches mounted on the platform and a support vessel, and the pipeline is stored on this second vessel. Furthermore, the document describes the relative movement between the vessel and the platform to make the proposed configuration feasible. Although the invention also relates to the removal of flexible pipelines, this document relates to an alternative method for installing subsea systems with unconventional configurations, but using the same means as those replaced by the proposed invention.

[0004] Document PI 1003096-4A2 relates to a floating system for installing or removing subsea equipment and structures. In one embodiment of the document, the system is designed as a floating system with a barge-like structure having an inverted U-shaped hull point, on which one or more subsea structures or equipment are supported and transported during both installation and removal operations. In another embodiment, two service vessels designed and constructed to work with components or joints interconnected by removable structures can be used, resulting in a unique floating system with double the carrying capacity and greater space availability for transporting or recovering large subsea equipment, in addition to optimizing the onboard crew. Besides optimizing the onboard crew, such a system can also have removable structures with drill turrets and perform well start-up operations. One of the objectives disclosed in the document is to develop a low-cost floating system and vessel with high operational flexibility, enabling the system and vessel to be allocated under both long-term and opportunity contracts, and possessing the capability to perform a variety of installation and intervention operations on subsea equipment. The document also aims to develop new concepts for floating systems, vessels, and installation or recovery methods. These concepts eliminate the need for rigs or large vessels specifically designed for cargo-dropping operations, offering greater flexibility and lower costs for different types of operations, and forming the basis for developing deepwater oil fields. While the document addresses systems for removing equipment from the sea, it makes no mention of the use of coils and reels for winding pipes and storing them on board, nor of operations for collecting pipes.

[0005] Document WO2012056132A1 relates to an apparatus for loading, transporting, and installing flexible conduits, such as pipes, control umbilical cables, or cables, placed on floating supports for offshore installation. More specifically, the object of this document is to provide a device for storing and handling flexible conduits laid on a ship, which enables the laying of longer flexible conduits at sea, and is easier and faster; and more specifically, the device enables easier and faster cleaning of the ship deck after the conduit laying operation is completed, and, if necessary, reinstallation of the device for new conduit laying as easily and quickly as possible using relatively small handling equipment, allowing on-site handling for new conduit laying if necessary. Although apparatus for performing the collection and winding of flexible conduits is also disclosed, the development of specialized coils that are thrown onto the seabed and connected to the portion to be collected is not mentioned, still involving commonly used technologies for which alternatives are sought.

[0006] The present invention relates to a device for collecting flexible pipes without the use of a dedicated vessel, which differs from devices disclosed in prior art documents. Summary of the Invention

[0007] This invention relates to a device for collecting flexible pipelines without the use of dedicated vessels, utilizing low-cost resources and not aiming to prevent damage to such equipment during handling, as the device is suitable for pipelines at the end of their service life or already damaged. These types of pipelines are a primary responsibility for some oil industry operators. The technology used during oilfield decommissioning or even in the pipeline collection phase where there is no prospect of use utilizes vessels with minimal adaptability. These vessels rely on the presence of collection / throwing wheels with a much smaller diameter compared to those used in conventional vessels, and these vessels also have space on deck for positioning vertical reels for hydraulic actuation.

[0008] Such collection can be carried out directly from the ship's deck, or alternatively, by using a special coil that is thrown onto the seabed and connected to the end of the section to be collected.

[0009] The purpose of this invention

[0010] This invention aims to collect discarded submarine flexible pipes using low-cost resources.

[0011] This invention aims to utilize resources that do not focus on preventing damage to flexible conduits during handling.

[0012] This invention aims to allow PLSVs (Pipeline Supply Vessels) to be used in other, more targeted activities, as PLSVs are highly demanded and costly resources, and are more complex than the resources required for the operations under discussion.

[0013] Another objective of this invention is to reduce the operational costs of collecting flexible pipes per kilometer that have no prospect of reuse. Attached Figure Description

[0014] The invention will now be described in more detail with reference to the accompanying drawings, which illustrate examples of the invention in a schematic manner and without limiting the scope of the invention. In the drawings, the following are present:

[0015] - Figure 1 The illustration shows a vessel (b) with a simplified collection system compared to a conventional vessel (a);

[0016] - Figure 2 It details even more complex configurations commonly used for throwing and collecting pipes;

[0017] - Figure 3 A typical tensioner used in throwing and collecting flexible conduits is shown;

[0018] - Figure 4 The illustration shows a conventional coil used for storing, transporting, and handling flexible tubing;

[0019] - Figure 5The invention provides a detailed description of an apparatus for collecting flexible tubes on the seabed;

[0020] - Figure 6 The auxiliary winding system for the equipment to be used in both the seabed and land tunnels is described in detail;

[0021] - Figure 7 Details on the use of Figure 6 The items shown are applicable to accessories for different pipe diameters;

[0022] - Figure 8 A typical flexible pipe connector with a traction head installed is shown.

[0023] - Figure 9 A stop collar is shown for use in cases where a pipe has been cut at one end and no connector is present at the other end. Detailed Implementation

[0024] First, it should be emphasized that the following description will begin with preferred embodiments of the invention. However, it will be apparent to any person skilled in the art that the invention is not limited to these specific embodiments, but rather to the scope defined by the claims.

[0025] The support vessel (2) has sufficient deck space to accommodate the vertical coil (40), which is longitudinally aligned with the vessel (2) to allow for the deployment of cables and accessories located within it. When used on board, the coil (40) is connected to a towing head (72) (for connecting to the accessories of the pipe to be collected) by means of an ROV (Remotely Operated Subsea Vehicle) obtained by the vessel itself, preferably or by a dedicated vessel, and is pulled by a collection wheel (61) until the end to be collected reaches the vertical coil (40); there is a connection between this end and the vertical coil (40) from which the collection of pipe (7) begins. Due to the load observed during collection, the coil (40) will be securely interconnected with the deck of the support vessel (2). Hydraulic drive via a motor (4) and possibly a gearbox will be able to pull the pipe (7) to be collected until the vertical coil (40) or a set of similar coils is loaded.

[0026] Speed ​​control is performed in a manner similar to that of conventional vessels (PLSV) (1), but without the use of typical equipment such as tensioners (or “tracks”) (5) or other structures or equipment designed to ensure the integrity of the pipeline (6, 62) during handling. Among these devices, even more complex structures have been observed, which are not limited to simple throwing wheels, but rather inclined structures (63) with throwing pulleys (62) having fixed tensioners (51).

[0027] The aim is to enable the deck's capacity and arrangement to accommodate more than one vertical coil (40), thereby increasing autonomy and reducing the sailing time for unloading materials. The vertical coil (40) can be installed from land onto the deck of the support vessel (2) or even unloaded from the deck of the support vessel (2) onto land.

[0028] Due to the observed low load, this configuration is preferred for collecting pipes in shallow water, except when carried out in an emergency manner above sea level (8).

[0029] Alternatively, due to the weight of the pipe and the simplicity of the support vessel (2), the support vessel (2) can drop the dedicated collection coil (9) onto one end of the pipe (7) resting on the seabed, whether in shallow or deep water. The pipe (7) will be connected to the dedicated collection coil (9) by means of a cable present in the dedicated collection coil (9) and by means of a structure of ROV, the ROV guiding the pipe (7) through an auxiliary winding mechanism (13), which acts as a guide and allows proper alignment of the pipe and thus allows winding of the pipe by means of a shaft (14), thereby making full use of the winding capability of the dedicated collection coil (9). The dedicated collection coil (9) must have radial rods (11) embedded in a circular reinforcing structure (10) typically observed in conventional storage coils (3).

[0030] The auxiliary winding mechanism (13) has a cavity (17) that works in conjunction with the transverse rod (14) so ​​that with each full turn of the coil (9), the auxiliary winding mechanism (13) moves laterally by a diameter equivalent to that of the pipe (7) so that the pipe is wound in the lateral position of the previous turn on the next turn of the coil.

[0031] The auxiliary winding mechanism (13) must have separation parts (18) surrounding the pipe (7) to align the path of the pipe (7) with the path required for proper winding. These separation parts (18) must have facilities operated by the ROV for opening (181) and closing, as well as locking by latches (20) that will hold the parts of the separation parts (18) together.

[0032] If it is necessary to adapt the auxiliary winding mechanism (13) to different diameters, inserts (31, 32) can be installed in the cavity (19) using fasteners (33). The diameter of the cavity (19) must be compatible with the maximum outer diameter of the pipe (7) within a range of 35 cm. Each insert (31, 32) must meet the range of outer diameters that allows the pipe (7) to pass through the insert and to secure the end connector (71) when collection is complete. The minimum expected diameter is within a range of 10 cm.

[0033] The radial rod (11) must have a spring-loaded or hydraulically actuated telescopic configuration so that it can extend as the dedicated collection coil (9) is filled with the collected pipe. The reason for not using a modified conventional coil (3), i.e., a circular reinforcing structure (10), to bear the entire radial extension comprised of the useful volume of such a coil, is that such a conventional coil would have a high probability of jamming or becoming stuck on the seabed. The reinforcing circular structure also serves as a guide for the radial rod (11). This radial rod (11) acts as a stop to stabilize the positioning of the pipe (7) during and after collection. The curvature of the surface of the dedicated collection coil (9) on which the pipe will be deposited can be much greater than that observed in conventional structures; that is, while the inner diameter of a conventional coil (3) is approximately 2 to 3 meters to prevent damage to the pipe when coiled, the dedicated collection coil (9) of this invention can have an inner diameter of approximately 1 meter because there is no requirement to avoid damaging the pipe (7) to be collected. This also increases the load-bearing capacity of the coil.

[0034] For collecting the conduit (7), a hydraulic motor (4) located in a dedicated collection coil (9) is powered by an umbilical cable consisting of hydraulic hoses that allow fluid to circulate in both directions (surface / motor and motor / surface), thereby driving the dedicated collection coil (9) to move and keep the conduit pulled for proper winding and collection. The hydraulic motor (4) may have a set of valves for better speed control and facilitates the arrangement of other hydraulic components that can be used in the dedicated collection coil (9), such as radial rods (11).

[0035] The rotation of the transverse bar (14) is connected to the rotation of the shaft of the dedicated collection coil (9) via a synchronous belt, thus allowing the rotation of the transverse bar (14) to be configured according to the diameter of the pipe to be collected and the steps of translating the auxiliary winding mechanism (13). Different configurations of grooves can be used in the transverse bar (14) to accommodate different outer diameter ranges of the pipes (7) to be collected. The vast majority of pipes to be collected have diameters in the range of 4 to 6 inches (10.16 cm to 15.24 cm), thus requiring a reduction in the number of configurations of the transverse bar (14).

[0036] The clutch system is desired to allow relative movement of the inner portion of the coil (9) relative to the radial rod (11) in order to keep the pipe (7) taut.

[0037] In the case of a hydraulically actuated radial rod (11), it is necessary to provide a greater number of hydraulic hoses in the umbilical cable, or to provide a set of hydraulic directional valves in the block including the motor (4). In this case, in addition to the hydraulic motor, a hydraulic circuit will also be included for actuating the motor itself and the cylinder that will act on the rod (11).

[0038] To align the coil with the path of the pipe (7), a steel cable from the ship (2) is connected to an eyelet (16). This eyelet is attached to the longitudinal rod (12) and the axle of the wheel (15), components that facilitate the movement of the dedicated collection coil (9) on the seabed. Due to the need for operation at great depths, the wheel (15) comprises a metal structure and a solid tire. Such a tire is wide enough to distribute the pressure applied to the seabed, preventing the tire from getting stuck and thus avoiding difficulties in overall tire displacement and operation.

[0039] With the aid of the cable, the ROV locks the traction head (72) into the dedicated collection coil (9), or, in the absence of the traction head, locks the connector (71) at the first end into the dedicated collection coil (9) to initiate winding by the drive of the hydraulic motor (4). The pipe (7) must be housed inside the auxiliary winding mechanism (13), which will assemble around the pipe (7) with the aid of the ROV. After this assembly, the vessel (2) provides assistance in the direction of displacement of the dedicated collection coil (9). Upon reaching the connector (71) at the second end, if a second connection portion is present, the separation component (18) will be opened by unlocking the locking element (20), and subsequently, the separation component (18) will close to continue collecting the pipe (7) until the pipe (7) is completely collected. After the pipe (7) is collected, it will be kept taut, wherein the end connector (71) is forced against the cavity (19) or one of the inserts (31, 32) of the cavity (19).

[0040] In order to enable the pipe to be locked at the second end without the end connector (71), which is common in pipes that have been cut, it is necessary to install a stop collar (50) via ROV.

[0041] At the end of collection, the end connector (71) relative to the second end of the pipe (7) or the stop collar (50) is secured to the separation component (18), thereby preventing the pipe from unfolding during transfer to the ship by means of a hanger or A-frame. The dedicated collection coil (9) is pulled to the deck of the ship (2) and suspended through a set of eyelets (16 and 161), and the pipe (7) can be transferred to a regular coil (3) for reuse of the dedicated collection coil (9). For such suspension, all eyelets (16 and 161) must be used, i.e., the two points including eyelet (16) and the two points including eyelet (161).

[0042] The capacity of the dedicated collection coil (9) is related to the load capacity of the equipment installed in the naval resources. If there are two or more connected parts, the equipment must be able to collect the last part of the auxiliary winding mechanism (13) that serves as a guide for the pipe (7) through a second connector. The collection method can be provided for unloading the dedicated collection coil (9) onto the ship itself or into an auxiliary vessel for reusing the coil. The device for actuating the accessories of the dedicated collection coil (9) must be easily operable by an ROV.

[0043] To use the device correctly, it is recommended to follow these steps in sequence:

[0044] - The traction head (72) of the end connector (71) is connected to the dedicated collection coil (9) by means of an ROV;

[0045] - The tubular body of the pipe (7) is housed inside an auxiliary winding mechanism (13), which is assembled around the pipe (7) by means of an ROV;

[0046] -Use the boat (2) to pull the special collection coil (9) along the collection direction of the pipe (7);

[0047] - As the boat moves, a special collection coil (9) is rotated to collect the pipe (7), wherein the rod (11) is stuck in the sand, and the special collection coil (9) is hydraulically driven by a motor (4) to collect the pipe until the coil is fully loaded.

[0048] Alternatively, the auxiliary winding mechanism (13) will be de-equipped and re-equipped until the collection of the pipe (7) ends due to the connector that connects the different parts to each other if there are different parts.

Claims

1. A device for collecting flexible pipes without using a dedicated vessel, characterized in that, The equipment includes: at least one support vessel (2) having at least one vertical coil (40) interconnected with and longitudinally aligned with the deck of the support vessel; a remotely operated seabed vehicle and means for controlling the remotely operated seabed vehicle; and a collection wheel (61). The support vessel (2) is configured to drop a dedicated collection coil (9) near one end of a pipe resting on the seabed. The dedicated collection coil (9) includes a circular reinforcing structure (10) and a radial rod (11). The radial rod (11) extends along the radial direction of the circular reinforcing structure (10) and is embedded in the circular reinforcing structure (10). The radial rod (11) has a telescopic configuration that is spring-loaded or hydraulically actuated.

2. The device according to claim 1, characterized in that, The vertical coil (40) collects the flexible pipe (7) by hydraulic drive of the motor (4).

3. The device according to claim 2, characterized in that, During the hydraulic drive of the motor (4), speed control eliminates the use of the rail (5) or other structures or equipment designed to ensure the integrity of the pipe (7) during processing.

4. The device according to claim 1, characterized in that, The support vessel (2) has the capacity and deck arrangement to accommodate more than one coil (40).

5. The device according to claim 1, characterized in that, The special collection coil (9) has a smaller inner diameter than that of a conventional coil.

6. The device according to claim 1, characterized in that, The radial rod (11) allows the longitudinal rod (12) of the dedicated collection coil (9) to be pulled, thereby forcing the longitudinal rod (12) to rotate to change direction and follow the route of the pipe (7) to be collected.

7. The device according to claim 1, characterized in that, The radial rod (11) allows for stable positioning of the pipe (7) during and after collection.

8. The device according to claim 1, characterized in that, The dedicated collection coil (9) also includes: An auxiliary winding mechanism (13) is configured to ensure proper positioning and winding of the pipe (7) on the dedicated collection coil (9); Support system and mooring points, the support system and mooring points including eyelets (16, 161); and A motor (4) is configured to drive the shaft of the dedicated collection coil (9) to rotate so that the pipe (7) is wound around the dedicated collection coil (9).

9. The device according to claim 8, characterized in that, The motor (4) has a set of valves for assisting in the use of the radial rod (11).

10. The device according to claim 8, characterized in that, The device uses a timing belt that connects the shaft of the dedicated collection coil (9) to the transverse rod (14).

11. The device according to claim 10, characterized in that, The transverse bar (14) has different grooves to enable the auxiliary winding mechanism (13) to translate according to the outer diameter of the pipe (7) to be collected.

12. A method for collecting flexible conduits using a dedicated collection coil (9) as defined in claim 1 without using a dedicated vessel, characterized in that, The method comprises the following steps: - Throw the dedicated collection coil (9) near one end of the pipe (7) resting on the seabed; - The towing head (72) of the end connector (71) is connected to the dedicated collection coil (9) by means of a remotely operated subsea vehicle; - A portion of the pipe (7) is housed inside an auxiliary winding mechanism (13), which will be assembled around the pipe (7) by means of the remotely operated subsea vehicle (ROV); - Use the support vessel (2) to pull the special collection coil (9) along the collection direction of the pipe (7); - When the support vessel (2) moves, the dedicated collection coil (9) is rotated to collect the pipe (7), wherein the radial rod (11) is stuck in the sand.

13. The method according to claim 12, characterized in that, The dedicated collection coil (9) collects the pipe (7) by hydraulic drive of the motor (4) until the dedicated collection coil (9) is fully loaded.

14. The method according to claim 12, characterized in that, At the end of the collection, the end connector (71) or stop collar (50) is secured, and the dedicated collection coil (9) is pulled onto the deck of the support vessel (2) through the eyelets (16, 161).

15. The method according to claim 12, characterized in that, The pipe (7) has multiple segments connected by connectors. During the collection of the pipe (7), the auxiliary winding mechanism (13) is opened to allow the connector to pass through when the connector passes through it, and the auxiliary winding mechanism (13) is closed again after the connector passes through it.

Images