METHOD AND SYSTEM FOR PREPARING SUBSEA EQUIPMENT FOR USE WITH DIVERSE INSTALLATION METHODS

Description

1 / 10 METHOD AND SYSTEM FOR PREPARING SUBSEA EQUIPMENT FOR USE WITH DIVERSE INSTALLATION METHODS Field of invention

[001] The present invention falls within the field of techniques and technologies for the preparation, recovery or recommissioning of subsea equipment. More specifically, the present invention relates to a method and system for preparing subsea equipment for use with diverless installation means. Fundamentals of the invention

[002] There is a growing demand for diverless operations, i.e., those carried out only by remotely operated vehicles (ROVs), for the installation of traction heads, CBs, for the retrieval of flexible pipelines by PLSV type vessels and / or for the installation of blind flanges for the temporary abandonment of pipelines.

[003] Currently, the pull heads and blind flanges for these operations, more particularly pull heads and blind flanges that follow API standards, as illustrated in Figure 1, need to be prepared by performing mechanical surface treatment and welding the nuts into the existing holes. The aforementioned welding of the nuts into the existing holes is necessary to allow the installation (or pre-installation) of studs in the respective holes. Then, and after positioning the API flanges in the desired location, the ROV can finalize the torqueing of the connection using its own tools, such as screwdrivers and torque wrenches.

[004] In general, the current sequence of activities for preparing the pull head and / or blind flange comprises: - Logistics for shipping materials from vessels and / or Petrobras stocks to carry out the preparation / adaptation process on land, as illustrated in Figure 1; - Machining team to prepare nuts (recess of approximately 2.0 mm on one end). Petition 870240110893, dated 12 / 27 / 2024, page 31 / 50 2 / 10 of the nut) for subsequent welding of these onto the drive head / blind flange, as illustrated in figure 2. The preparation / machining of the nuts aims to ensure that they are centered in the existing holes in the flanges during the welding process; - A boilermaking team will prepare the installation area, as illustrated in Figure 3, as well as position and weld the nuts centered with the flange holes using the recess made in the previous step, and then perform intermittent welding of the nuts and, optionally, welding of an eyelet and handling handles for the ROV, as illustrated in Figure 4; - Painting team for treating the flange and nuts after the adaptation process of the CBs / blind flanges, as illustrated in figure 5; and - Logistics of shipping materials to the vessels.

[005] Thus, the aforementioned preparation makes it possible for the installation of traction heads and / or blind flanges to be carried out in a diverless manner. However, due to mechanical treatment and welding operations, the traction head loses its API qualification / certification for lifting pipelines. Consequently, the lines are retrieved with traction heads that do not meet the API standard.

[006] Additionally, there is no nut material standard that indicates the use of welding for application in a submarine environment, as this operation alters the microstructure of the material, affecting its structural integrity.

[007] In this regard, it will also be appreciated that the aforementioned preparation requires a large number of resources and materials, such as: - availability of a large quantity of pull heads, studs and nuts; Petition 870240110893, dated 12 / 27 / 2024, page 32 / 50 3 / 10 - Machining and welding teams for making the templates and welding the nuts; - Painting team to paint the nuts after the welding and mechanical treatment process of the CT; and - Logistics of shipping materials to the vessels.

[008] Therefore, there is a need for a traction head and / or blind flange preparation solution that maintains the integrity of the traction head and complies with the API standard by not employing welding in the nut fastening process. Furthermore, there is a need for a traction head and / or blind flange preparation solution with flexible installation, whether on-board or onshore, that optimizes the time and cost of said operation. State of the art

[009] In the state of the art, there are some documents focused on devices for preparing and / or adapting holes for connection between elements.

[010] Document US2632355 discloses a threaded nut with a flange that is adapted to engage a bolt disposed through a panel of wood, sheet metal or similar. Said engagement flange on the building support panel is enhanced by means of corrugations, so that it is able to withstand high stresses without substantial deformation.

[011] Document US20090136320 discloses an internally threaded connector. The internally threaded connector device is a thin-walled internally threaded tube. A relatively short portion of the device includes a polygonal wrench-tightening flange area.

[012] Document US8267630 discloses a fastening system comprising a first material having a first hole, a second material having a second hole, a bushing and a threaded screw. The bushing is located in the second hole and has a first end resting against the first material and a second end flanged to secure the bushing to the second material. Petition 870240110893, dated 12 / 27 / 2024, page 33 / 50 4 / 10 material. A threaded screw extends through the first hole and into the bushing to secure the first material flush with the second material.

[013] In view of the disclosure of the state of the art, the characteristics and advantages of the present invention will become clear from the detailed description below and with reference to the accompanying drawings. Brief description of the invention

[014] The present invention discloses a method and system for preparing a subsea device (2) for use with diverless installation means. The method comprises the steps of: fitting a bushing (1) into respective holes of the subsea device (2) on a first side, wherein the bushing (1) comprises a flange and a cylindrical body; locking nuts (4) onto a first end of respective studs (3); inserting, on a second side, a second end of the studs (3) into the respective holes; and screwing the second end of the studs (3) into the respective bushings (1) already fitted into the respective holes of the subsea device (2). The system comprises a plurality of bushings (1) composed of a flange and a cylindrical body, a plurality of studs (3), and a plurality of nuts (4), said elements being used for preparing a subsea device for use with diverless installation means. Brief description of the figures

[015] In order to complement the present description and obtain a better understanding of the characteristics of the present invention, a set of figures is presented, where, in an exemplary, non-limiting manner, preferred embodiments thereof are represented.

[016] Figure 1 illustrates the logistics of sending the traction head / blind flange to carry out the adaptation process on land. Petition 870240110893, dated 12 / 27 / 2024, page 34 / 50 5 / 10

[017] Figure 2 illustrates the preparation / machining of the nuts to enable their centering for subsequent welding.

[018] Figure 3 illustrates the preparation of an area for installing nuts by a boilermaking team.

[019] Figure 4 illustrates the welding of the centered nuts with the flange drilling, and the optional welding of an eyelet and handling handles for the ROV.

[020] Figure 5 illustrates the treatment of the flange and nuts by a painting team.

[021] Figure 6 illustrates a traction head / blind flange prepared / assembled according to the present invention.

[022] Figure 7 illustrates a top view and corresponding cross-sectional cut of a traction head / blind flange prepared / assembled according to the present invention.

[023] Figure 8 illustrates an enlargement of the bushing accommodation details in a recess in the drive head / blind flange.

[024] Figure 9 illustrates a perspective view of the preferred bushing configuration with a hexagonal flange.

[025] Figure 10 illustrates a top view with corresponding cross-sectional cut of the hexagonal bushing.

[026] Figure 11 illustrates a top view and corresponding cross-sectional cut of another preferred configuration of the bushing, with a circular flange with a cut. The said cut acts as a stop to prevent the bushing from rotating. Detailed description of the invention

[027] The present invention relates to a method and system for preparing a subsea equipment (2) for use with diverless installation means, having particular application in diverless installation interventions of subsea equipment such as traction heads and blind flanges. Petition 870240110893, dated 12 / 27 / 2024, page 35 / 50 6 / 10

[028] In general, and as illustrated in figures 6 to 8, the invention comprises the use of a bushing (1) that allows the installation of studs (3) and nuts (4) on a subsea equipment (2) without the need for surface preparation or welding, thus maintaining the qualification / certification, such as API certification, of said equipment. Furthermore, said bushing (2) retains the studs (3) and nuts (4) on a subsea equipment (2) so that it can be positioned and then installed by diverless installation means, such as, for example, by means of an ROV. Thus, it seeks to reduce logistics and preparation costs, in addition to meeting the requirements of the API standard.

[029] It will be appreciated that the present invention can be designed for use with various dimensions of subsea equipment and their respective pressure classes, depending on the context of use. For example, the invention can be designed for pull heads and / or API flanges with dimensions of 2 9 / 16, 4 1 / 16, 7 1 / 16, 9 or 11, in pressure classes of 5,000 psi and 10,000 psi.

[030] In this context, and without limitation, some advantages of the present invention compared to the state are: - to enable the centralized installation of nuts and / or studs on the traction head and blind flanges without the need for treatment, welding, or shipping this underwater equipment to a land-based base; - To ensure the integrity of the drive head and blind flanges, thus complying with API standards, as no welding is used in the nut fastening process; - Greater resource flexibility, since materials could be sent directly to specialized remote strand support vessels (RSVs) during their stay in port, or received directly from vessels designed for laying and retrieving lines (PLSVs). These materials... Petition 870240110893, dated 12 / 27 / 2024, page 36 / 50 7 / 10 can also be abandoned on the seabed or transshipped to RSVs or platforms; - to keep assemblies of the present invention on board vessels to enable their installation by onboard crews. - Very short installation time, significant reduction of health, environmental and safety (HSE) risks due to not involving hot work and painting; and - Low manufacturing and installation cost for drive heads or blind flanges.

[031] According to a preferred embodiment of the present invention, a method / process for preparing a subsea device (2) for use with diverless installation means is disclosed. Said method comprises at least the following steps: a) to accommodate a bushing (1) in respective holes of the subsea equipment (2) on a first side, wherein the bushing (1) comprises a flange and a cylindrical body; b) lock nuts (4) on a first end of respective studs (3); c) introduce, from a second side, a second end of the cases (3) into the respective holes; and d) screw the second end of the studs (3) into the respective bushings (1) already fitted into the respective holes of the subsea equipment (2).

[032] Wherein the method, in step a) of accommodating the bushing (1), may also comprise positioning it in a recess on the first side of the subsea equipment (2). Said recess, or groove, is preferably a recess configured for the installation of a ring gasket. Said ring gasket may be a BX ring commonly used in the oil and gas industry for flanges, thrust heads, pipelines, valves and pressure vessels in refineries, petrochemical industries, equipment Petition 870240110893, dated 12 / 27 / 2024, p. 37 / 50 8 / 10 wellhead and drilling, Christmas tree valves and lines.

[033] It will be appreciated that the step of fitting the bushing (1) into the respective holes of the subsea equipment (2) can be carried out without the use of specialized tools. Furthermore, the step of screwing d) the second end of the studs (3) into the respective bushings (1) can involve the use of a hand wrench.

[034] Furthermore, preferably where, on the first side, the bushing flange (2) is positioned on the side of a flexible duct connector.

[035] The said bushing (1) is an API flange bushing preferably made from any of polypropylene, brass or bronze.

[036] As illustrated in greater detail in figures 9 and 10, said bushing flange (1) may comprise a hexagonal perimeter. Alternatively, and as illustrated in figure 11, said bushing flange (1) may comprise a circular circumference with a cut. Said cut is preferably a circular segment or disc segment, thus resulting in a flange with the shape of a circular arc with a chord connecting its endpoints.

[037] The said cylindrical body of the bushing (1) preferably consists of a smooth outer part and an inner part threaded along the entire length of the bushing (1), such that the threaded part is found both on the body and on the flange of the bushing (1).

[038] It will be appreciated that the method may optionally include a further step of welding an eyelet and handling handles on the subsea equipment (2).

[039] According to another preferred embodiment of the present invention, a preparation system for equipment Petition 870240110893, dated 12 / 27 / 2024, page 38 / 50 9 / 10 submarine (2) for use with diverless installation means is disclosed. The said system comprises: a plurality of bushings (1) consisting of a flange and a cylindrical body; a plurality of cases (3); and a plurality of nuts (4), wherein the bushings (1) are accommodated in respective holes of the subsea equipment (2) on a first side, wherein the nuts (4) are locked in a first end of respective studs (3); and wherein a second end of the studs (3) is introduced on a second side into the respective holes of the subsea equipment and threaded into the respective bushings (1) already accommodated in the respective holes.

[040] The first side of the subsea equipment (2) preferably comprises a recess to accommodate the bushing (1). Said recess, or groove, is preferably a recess configured for the installation of a ring gasket. Said ring gasket may be a BX ring commonly used in the oil and gas industry for flanges, thrust heads, pipelines, valves and pressure vessels in refineries, petrochemical industries, wellhead and drilling equipment, Christmas tree valves and lines.

[041] It will be appreciated that fitting the bushing (1) into the respective holes of the subsea equipment (2) can be done without the use of specialized tools. Furthermore, screwing the second end of the studs (3) into the respective bushings (1) can involve the use of a hand wrench.

[042] Furthermore, preferably where, on the first side, the bushing flange (2) is positioned on the side of a flexible duct connector. Petition 870240110893, dated 12 / 27 / 2024, pp. 39 / 50 10 / 10

[043] The said bushing (1) is an API flange bushing preferably made from any of polypropylene, brass or bronze.

[044] As illustrated in greater detail in figures 9 and 10, said bushing flange (1) may comprise a hexagonal perimeter. Alternatively, and as illustrated in figure 11, said bushing flange (1) may comprise a circular circumference with a cut. Said cut is preferably a circular segment or disc segment, thus resulting in a flange with the shape of a circular arc with a chord connecting its endpoints.

[045] The said cylindrical body of the bushing (1) preferably consists of a smooth outer part and an inner part threaded along the entire length of the bushing (1), such that the threaded part is found both on the body and on the flange of the bushing (1).

[046] Thus, those skilled in the art will appreciate the knowledge presented here and will be able to reproduce the invention described in the embodiment presented and in other variants, covered within the scope of the appended claims. Petition 870240110893, dated 12 / 27 / 2024, pages 40 / 50

Claims

1 / 2 CLAIMS 1. Method of preparing a subsea equipment (2) for use with divertless installation means, characterized in that it comprises the steps of: e) fitting a bushing (1) into respective holes of the subsea equipment (2) on a first side, wherein the bushing (1) comprises a flange and a cylindrical body; f) locking nuts (4) on a first end of respective studs (3); g) inserting, on a second side, a second end of the studs (3) into the respective holes; eh) screwing the second end of the studs (3) into the respective bushings (1) already fitted into the respective holes of the subsea equipment (2).

2. Method according to claim 1, characterized in that accommodating the bushing (1) further comprises positioning it in a recess on the first side of the subsea equipment (2).

3. Method according to claim 1, characterized in that screwing the second end of the studs (3) into the respective bushings (1) involves the use of a hand wrench.

4. Method according to claim 1, characterized in that said bushing flange (1) comprises a perimeter or circumference of hexagonal or circular shape with a cut.

5. Method according to claim 1, characterized in that said cylindrical body of the bushing (1) consists of a smooth outer part and an inner part threaded along the entire length of the bushing (1).

6. Method according to claim 1, characterized in that it optionally further comprises a welding step for an eyelet and handling handles.

7. System for preparing a subsea equipment (2) Petition 870240110893, of 12 / 27 / 2024, page 41 / 50 2 / 2 for use with diverless installation means, characterized in that it comprises: a plurality of bushings (1) composed of a flange and a cylindrical body; a plurality of studs (3); and a plurality of nuts (4), wherein the bushings (1) are accommodated in respective holes of the subsea equipment (2) on a first side, wherein the nuts (4) are locked in a first end of respective studs (3); and wherein a second end of the studs (3) is introduced on a second side into the respective holes of the subsea equipment and threaded into the respective bushings (1) already accommodated in the respective holes.

8. System according to claim 7, characterized in that the first side of the subsea equipment (2) comprises a recess to accommodate the bushing (1).

9. System according to claim 7, characterized in that screwing the second end of the cases (3) into the respective bushings (1) involves the use of a manual wrench.

10. System according to claim 7, characterized in that said bushing flange (1) comprises a perimeter or circumference of hexagonal or circular shape with a cut.

11. System according to claim 7, characterized in that said cylindrical body of the bushing (1) consists of a smooth outer part and an inner part threaded along the entire length of the bushing (1).

12. System according to claim 7, characterized in that the bushing (1) is an API flange bushing and is manufactured from any one of polypropylene, brass or bronze. Petition 870240110893, dated 12 / 27 / 2024, pp. 42 / 50

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