System and method for shutting off a pipe

A motorized pipeline sealing system with flexible linking and support assemblies ensures stable sealing and inerting across complex pipeline layouts, addressing navigation and detachment issues in nuclear power plants.

WO2026104776A1PCT designated stage Publication Date: 2026-05-21ENDEL
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Patent Information

Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
ENDEL
Filing Date
2025-11-04
Publication Date
2026-05-21

AI Technical Summary

Technical Problem

Existing pipeline sealing systems struggle to navigate bends and maintain the sealing device's attachment in complex pipeline circuits, particularly in nuclear power plants, due to their reliance on horizontal movement and lack of flexibility.

Method used

A motorized transport subsystem with flexible linking components and mobility assemblies that allow the sealing device to transition between transport and release configurations, ensuring stability and sealing across bends and non-horizontal sections by deploying support points on the pipeline's inner wall.

Benefits of technology

The system effectively seals and moves within pipelines with bends and varying orientations, preventing detachment of the sealing device even if the inflatable bladder deflates, and enables inerting by injecting inert gas to maintain a sealed and inert environment.

✦ Generated by Eureka AI based on patent content.

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Abstract

The invention relates to a system (10) for shutting off a pipe (20) comprising a transport sub-system (11) and a shut-off device (12), configured to move inside the pipe (20), the pipe (20) being potentially complex and possibly comprising elbows, the system (10) being further configured to change alternately and reversibly from a transport configuration to a release configuration (CLS) of the system, in which release configuration the shut-off device (12) is detached from the transport sub-system (11), the system (10) further comprising a mobility sub-assembly (14, 14', 14'') configured to be mounted on the transport sub-system (11) and on the shut-off device (12) by resting on at least two bearing points distributed over a section of an interior wall of the pipe (20) while simultaneously providing longitudinal mobility of the system (10); the shut-off device (12) being configured to change from a shut-off configuration (COB) to an open configuration (COU) in which the shut-off sub-assembly (15) does not sealingly shut off the pipe (20); the shut-off device (12) further comprising a sub-assembly (16) for mechanically holding the shut-off device (12) resting on the interior wall of the pipe (20).
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Description

[0001] DESCRIPTION

[0002] TITLE: System and method for sealing a pipe.

[0003] The present invention relates to the field of devices and methods for sealing and / or inerting a pipeline.

[0004] It is known to use a system comprising a transport trolley configured to be mobile inside a pipeline and to transport at least one sealing device configured to be deposited by the transport trolley at a point in the pipeline and to seal the pipeline by means of an inflatable bladder.

[0005] The drawback of known systems is that they cannot navigate bends in a pipeline, and the sealing device is at risk of detaching from its mounting point if the bladder accidentally deflates. These drawbacks are particularly significant when implementing such systems in the complex pipeline circuits of a nuclear power plant. Furthermore, known systems are not designed to move within a pipeline that is not substantially horizontal, especially within a pipeline that is nearly vertical or contains bends. This is because the transport trolley for known systems is usually designed to rest, under its own weight, on the bottom of the pipeline in which it moves, or to move only in straight sections of piping.

[0006] The invention therefore aims to provide a solution to all or part of these problems.

[0007] To this end, the present invention relates to a pipeline sealing system comprising a transport subsystem and a sealing device, the transport subsystem being motorized, configured to move inside the pipeline in the direction of a longitudinal extension of the pipeline, the system being further configured to switch alternately and reversibly from a transport configuration of the system in which the sealing device is connected to the transport subsystem by a flexible linking component, to a release configuration of the system in which the sealing device is detached from the transport subsystem,

[0008] the system further comprising at least one mobility sub-assembly configured to be mounted on the transport sub-system and on the sealing device and deployed transversely to the longitudinal extension of the pipeline so that the at least one mobility sub-assembly is supported on at least two support points distributed over a section of an inner wall of the pipeline when deployed, so that the system is mechanically returned, transversely to the longitudinal extension of the pipeline, towards a central area of ​​the pipeline section, while simultaneously ensuring longitudinal mobility of the system in the direction of the longitudinal extension of the pipeline;

[0009] the sealing device comprising a sealing sub-assembly configured to transition from a sealing configuration in which the sealing sub-assembly provides a tight seal of the pipeline at a point of sealing the pipeline, the sealing being tight against a fluid flowing in the pipeline at the point of sealing the pipeline, to an opening configuration in which the sealing sub-assembly does not provide a tight seal of the pipeline;

[0010] The sealing device further comprises a retaining sub-assembly configured to transition from a mechanically held configuration, in which the retaining sub-assembly mechanically holds the sealing device against the inner wall of the pipe, to a free configuration, in which the sealing device is not held by the retaining sub-assembly. In one embodiment, the sealing point is a position, along an axis along the longitudinal extension of the pipe, of a central point of a cross-section relative to the axis, with sealing ensured over the entire cross-section centered on said central point.

[0011] According to one embodiment, the fluid is at least one of a gas, a liquid, or even a dust aerosol.

[0012] According to these provisions, the sealing system is capable, thanks to the flexibility of the linking components between the system components, and the distribution of the support and rolling points inside the pipeline, of moving inside a pipeline even if the pipeline has bends and even if some portions of the pipeline are not horizontal; the system is also capable, thanks to the mechanical support sub-assembly, of placing the sealing device at a sealing point, without the sealing device risking detachment if the sealing sub-assembly were to fail.

[0013] According to one embodiment, the invention comprises one or more of the following features, alone or in a technically acceptable combination.

[0014] According to one embodiment, when the system is in transport configuration, and the sealing sub-assembly is in open configuration, and the holding sub-assembly is in free configuration, the system is configured to transport the sealing device from one point to another point in the pipeline, in both directions of the longitudinal extension direction of the pipeline.

[0015] According to one embodiment, when the sealing sub-assembly is in the open configuration, and the holding sub-assembly is in the mechanical holding configuration, the system in the transport configuration is configured to transport the sealing device from one point to another point in the pipeline, in only one direction of the longitudinal extension direction of the pipeline, movement in the other direction being made impossible by the mechanical holding sub-assembly;This facilitates the transition from a system release configuration to a system transport configuration by allowing the system's transport subsystem in the release configuration to use the sealing device to move the system into the transport configuration, while simultaneously preventing the sealing device from detaching from the pipe wall in a direction opposite to the transport subsystem during the system's transition from the release configuration to the transport configuration.

[0016] According to one embodiment, the retaining sub-assembly can take the mechanical retaining configuration when the sealing sub-assembly is in the sealing configuration or when the sealing sub-assembly is in the opening configuration, to prevent the sealing device from detaching from the pipe wall in the latter case.

[0017] According to one embodiment, the transport subsystem comprises one or more motorized elementary modules for propelling or pulling the closing device and, where appropriate, other non-motorized elementary modules of the transport subsystem.

[0018] According to one embodiment, the transport subsystem comprises an elementary module connected by the flexible linking component to the sealing device, or comprises an elementary module connected by the flexible linking component to the sealing device and connected by another flexible linking component to at least one other elementary module, the at least one other elementary module and the elementary module and the sealing device each being circumscribed within a virtual geometric envelope having a transverse dimension measured in a plane transverse to the longitudinal extent of the system, and a longitudinal dimension measured along a longitudinal extent of the system, the longitudinal dimension being determined as a function of the transverse dimension, and at least one dimension of a pipe bend to allow the system in transport configuration to pass through the pipe bend.

[0019] According to one embodiment, the transverse dimension is a diameter of a section of the cylindrical envelope, and the longitudinal dimension is a length of the cylindrical envelope.

[0020] According to one embodiment, at least one dimension of a pipe bend is a radius of curvature of a central axis of the pipe and an inside diameter of a pipe section.

[0021] According to one embodiment, the function is written L=Sin(Arcos((D+RC-Dint / 2) / (RC+Dint / 2)))*2*(RC+Dint / 2), where RC is the radius of curvature, D the transverse dimension, and Dint the inner diameter.

[0022] According to these provisions, the sealing system in transport configuration is capable of transporting a sealing device by moving inside a pipeline having one or more bends whose radius of curvature is greater than or equal to the radius of curvature and whose internal diameter is greater than or equal to the internal diameter.

[0023] In one embodiment, each support point of at least two support points of at least one mobility sub-assembly comprises a wheel bearing against the inner wall of the pipeline. In another embodiment, at least two support points of at least one mobility sub-assembly comprise three support points distributed across the pipeline cross-section, with an angular sector of approximately 120 degrees between two successive support points of the cross-section.

[0024] According to one embodiment, at least one mobility subset comprises several mobility subsets offset from one another in the direction of the longitudinal extension of the system, and distributed respectively on the transport subsystem and on the sealing device.

[0025] According to one embodiment, an end portion of the linking component is equipped with a mobility sub-assembly. According to these provisions, when the system is in the release configuration, the linking component is held in the desired direction to facilitate the system's transition from the release configuration to the transport configuration.

[0026] According to one embodiment, the plurality of mobility subsets comprises at least two mobility subsets distributed over the transport subsystem and at least two other mobility subsets distributed over the closing device; according to these arrangements the mobility of the different devices of the system is ensured with better mechanical stability.

[0027] According to one embodiment, the sealing device is equipped with a single mobility sub-assembly; these arrangements are sufficient to ensure a minimum mechanical stability of the sealing device, on the one hand in the transport configuration of the system thanks to the mobility sub-assemblies distributed on the other devices of the system to which the sealing device is connected, on the other hand in the release configuration of the system thanks to the retention sub-assembly of the sealing device in mechanical retention configuration which cooperates with the mobility sub-assembly of the sealing device to ensure the stability of the sealing device in the release configuration of the system.

[0028] According to one embodiment, at least one mobility subset further comprises at least one elastic return mechanism, for example a spring, associated with the wheel configured to keep the wheel in contact with the point on the inner wall of the pipe.

[0029] According to one embodiment, the sealing sub-assembly comprises an inflatable component disposed around the sealing device, transverse to the longitudinal extension of the system and the pipeline, the inflatable component being deflated in the open configuration of the sealing sub-assembly, the inflatable component being further configured to ensure, in the inflated state, in the sealing configuration of the sealing sub-assembly, a first watertight contact with the inner wall of the pipeline at the point of sealing and a second watertight contact with the sealing device, so that in the inflated state of the inflatable component, the pipeline is hermetically sealed by the sealing device.

[0030] According to one embodiment, the inflatable component is an elastic membrane.

[0031] According to one embodiment, the support subassembly comprises at least two support components configured to be deployed in the mechanical support configuration, the at least two support components being deployed transversely to the longitudinal extension of the pipeline to be supported on different points of a section of the inner wall of the pipeline.

[0032] According to these provisions, when the inflatable component of the sealing device is accidentally deflated after being inflated in the sealing configuration of the sealing subassembly, the sealing device remains mechanically held by the holding subassembly.

[0033] According to one embodiment, the at least two retaining components are retracted with a single-acting cylinder, and deployed with a spring.

[0034] According to one embodiment, the cylinder is pneumatic.

[0035] According to one embodiment, the at least two retaining components include a unidirectional rolling component, the unidirectional rolling component being configured to provide mobility in only one direction of the longitudinal extension direction of the pipeline, the mobility being locked in the other direction.

[0036] According to one embodiment, the only direction of mobility is oriented from the closing device towards the transport subsystem.

[0037] According to these provisions, the sealing device is not at risk of detaching from the wall in the opposite direction to the direction of arrival of the transport subsystem, when the transport subsystem approaches the sealing device to load it and retrieve it in the system's transport configuration.

[0038] According to these provisions also, in the event of a leak in the air circuit of the cylinders configured to allow the passage to the free configuration of the holding sub-assembly, the sealing device may be pulled towards the exit even when the holding sub-assembly is locked in the holding configuration.

[0039] In one embodiment, the linking component includes an end portion configured to cooperate with a complementary element of the shutter device. In another embodiment, the end portion includes a camera configured to observe through the shutter device via a transparent wall when the end portion cooperates with the complementary element of the shutter device to connect the shutter device to the transport subsystem.

[0040] According to one embodiment, the elementary module is an inerting device, the inerting device comprising a sealing subset of the inerting device and an inerting subset, the sealing subset of the inerting device being configured to switch, when the system is in system release configuration, from an opening configuration to a sealing configuration in which the sealing subset of the inerting device provides a tight seal of the pipeline at another sealing point of the pipeline, the inerting subset being configured to inject an inert gas into the portion of the pipeline between the sealing point and the other sealing point.

[0041] According to these provisions, the sealed zone of the pipeline created between the two sealing points is inertized by the mixing of the inert gas with the gas previously existing in that same zone.

[0042] According to one embodiment, the inerting subassembly includes a purge, the purge being opened to purge some of the gas existing in the portion of the pipeline between the sealing point and the other sealing point before the injection of the inert gas.

[0043] According to one embodiment, the inert gas is denser than the existing gas, and the sealing device includes another purge, the purge of the inerting device being closed and the other purge being open to purge some of the existing gas in the portion of the pipeline between the sealing point and the other sealing point before the injection of the inert gas, an altitude of the purge of the inerting device being lower than an altitude of the other purge, or conversely, the purge of the inerting device being open and the other purge of the sealing device being closed to purge some of the existing gas in the portion of the pipeline between the sealing point and the other sealing point before the injection of the inert gas, an altitude of the purge of the inerting device being higher than an altitude of the other purge.

[0044] According to one embodiment, the inerting sub-assembly includes lighting and a camera allowing visual inspection of the section of pipe.

[0045] According to one embodiment, the inerting sub-assembly includes an oxygenometer to validate the oxygen level in the portion of the pipeline.

[0046] According to one embodiment, the linking component is configured to allow passage from the transport subsystem to the sealing device of an inflation circuit of the inflatable component of the sealing subassembly of the sealing device and / or of an activation circuit of a pneumatic cylinder of at least two holding components of the sealing device and / or of an electrical supply circuit of the sealing device.

[0047] According to one embodiment, the inflation circuit of the inflatable component of the sealing device and the activation circuit of a pneumatic cylinder of at least two retaining components of the sealing device are coupled such that the retraction of the pneumatic cylinder of at least two retaining components triggers the deflation of the inflatable component. The invention also relates to a method for sealing and / or inerting a pipeline in a nuclear power plant comprising the use of a system according to one of the preceding claims.

[0048] For its proper understanding, an embodiment and / or implementation of the invention is described with reference to the accompanying drawings, which represent, by way of non-limiting example, one embodiment or implementation of a device and / or method according to the invention. The same reference numerals in the drawings designate similar elements or elements with similar functions.

[0049] [Fig. 1] is an overview of a sealing and / or inerting system comprising a sealing device and a motorized transport subsystem comprising a complementary sealing and inerting device, according to an embodiment of the invention.

[0050] [Fig. 2] is a close-up and separate view of the inerting device and the sealing device of the system shown in Figure 1, according to one embodiment of the invention.

[0051] [Fig. 3] is a perspective view of the sealing device with its sealing sub-assembly in the open configuration, i.e. with the inflatable component deflated, and with its retaining sub-assembly in the free configuration, i.e. with the retaining components retracted, according to one embodiment of the invention

[0052] [Fig. 4] is a perspective view of the sealing device with its sealing sub-assembly in the sealing configuration, i.e. with the inflatable component inflated, and with the retaining sub-assembly in the mechanical retaining configuration, i.e. with the retaining components deployed, according to one embodiment of the invention

[0053] [Fig. 5] is another perspective view of the sealing device with its sealing subassembly in the open configuration, i.e., with the inflatable component deflated, and with the retaining subassembly in the free configuration, i.e., with the retaining components retracted, according to one embodiment of the invention; this other view also shows the complementary element of the sealing device configured to receive a terminal portion of the flexible linking component of the motorized transport subsystem not shown in this figure

[0054] [Fig. 6] is a schematic representation of an implementation of a sealing and inerting system according to an example of an embodiment in the transport configuration of the system on figure 6a, and in the release configuration of the system on figure 6b.

[0055] [Fig. 7] a schematic representation of a pipe bend, with the dimensional characteristics of the elementary modules, and of the sealing device of the sealing and inerting system according to an example of an embodiment, so that each elementary module, and the sealing device are each circumscribed, without the mobility subsets, within a virtual geometric envelope.

[0056] [Fig. 8] is a perspective view of the sealing device with its sealing sub-assembly in the open configuration, i.e. with the inflatable component deflated, and with its retaining sub-assembly in the free configuration, i.e. retracted, according to another embodiment of the invention, in which the retaining component includes a unidirectional rolling component.

[0057] The present invention relates to a sealing system 10 which allows a pipe to be sealed autonomously. The pipe may have several bends and vertical and horizontal sections.

[0058] The sealing system 10 includes a transport subsystem 11 and a sealing device 12, shown for example in Figures 1 and 2.

[0059] The sealing device 12 is configured to be coupled to the transport subsystem 11, which allows circulation in a complex piping system that may include: - several bends of up to 90°, which may be mounted in series,

[0060] vertical and horizontal potions, in the direction of ascent and descent,

[0061] The sealing device 12, once deposited by the transport subsystem 11, allows:

[0062] - using an inflatable component 15, for example an inflatable membrane 15, to isolate a portion of the piping while ensuring airtightness, dust and liquid splash resistance;

[0063] - using mechanical retaining components 16, for example clamps, and the inflatable membrane 15, to absorb additional axial forces of several kilograms, which ensures that it will remain at the sealing point PO in the piping, without risk of drifting.

[0064] This 12-gauge sealing device can cover a wide range of pipes, thanks to different models with different diameters:

[0065] - 8 inch model: specially adapted for 8” pipes”, for circulation and deployment in internal diameters between 170 mm and 190 mm.

[0066] - 10 to 16 inch model: the membrane support and membrane are adapted to the internal diameters considered. For example, the 10” model allows circulation and deployment in internal diameters between 200mm and 232mm.

[0067] The present invention therefore relates firstly to a sealing system 10 for a pipeline 20, the sealing system 10 comprising a transport subsystem 11 and a sealing device 12; the transport subsystem 11 is motorized and configured to move inside the pipeline 20 in the direction of a longitudinal extension of the pipeline 20, the system 10 being further configured to switch alternately and reversibly from a CTS transport configuration of the system 10, schematically illustrated in Figure 6a of Figure 6, in which the sealing device 12 is connected to the transport subsystem 11 by a flexible linking component 17, to a CLS release configuration of the system 10 in which the sealing device 12 is detached from the transport subsystem 11, schematically illustrated in Figure 6b of Figure 6.

[0068] As shown in Figures 1, 6a, and 6b, the transport subsystem 11 may include several devices, or elementary modules, linked together in pairs by a flexible linking component 17, 17', in particular several motorized modules which can add their motor power to move the sealing device 12; the transport subsystem 11 may also include, as will be described later, an inerting device 13, which also moves with the transport subsystem 11.

[0069] According to one embodiment, the transport subsystem 11 comprises an elementary module 13 connected by the flexible linking component 17 to the shuttering device 12; or, according to another embodiment, the transport subsystem 11 comprises an elementary module 13 connected by the flexible linking component 17 to the shuttering device 12, the elementary module 13 also being connected by another flexible linking component 17' to at least one other elementary module 13', 13”, the at least one other elementary module 13', 13” being able to comprise a series of several elementary modules 13', 13” connected to each other in pairs by other flexible linking components 17', 17” so as to form a train of other elementary modules 13”, 13' with a lead elementary module 13' connected to the elementary module 13 by another flexible linking component 17'.

[0070] According to one embodiment, at least one of the elementary modules 13, 13', 13" is motorized so as to propel and / or tow the other elementary modules and the shutter device 12. For example, the linking component 17 includes an end portion 18 configured to cooperate with a complementary element 19 of the shutter device 12, as illustrated in Figure 2 and Figure 6a. In particular, the end portion 18 may include a camera configured to observe through the shutter device 12 via a transparent wall when the end portion 18 cooperates with the complementary element 19 of the shutter device 12, as schematically illustrated in Figure 6a, to connect the shutter device 12 to the transport subsystem 11.

[0071] The sealing system 10 further comprises at least one mobility sub-assembly 14, 14', 14"; said mobility sub-assembly 14, 14', 14" is supported on at least two support points, for example three support points, distributed over a section of an inner wall of the pipe 20, so that the system 10 is mechanically recalled, transversely to the longitudinal extension of the pipe 20, towards a central area of ​​the section of the pipe 20, while simultaneously ensuring longitudinal mobility of the system 10 in the direction of the longitudinal extension of the pipe 20.For example, to ensure better stability at the support points of each mobility sub-assembly 14, 14', 14", the mobility sub-assembly 14, 14', 14" comprises, for example, three support points distributed over the section of the pipe 20, with an angular sector of approximately 120 degrees between two successive support points of the mobility sub-assembly 14, 14', 14". In particular, each support point of the mobility sub-assembly 14, 14', 14" comprises a wheel bearing against the inner wall of the pipe 20, with the axis of rotation of the wheel being directed in a plane transverse to the direction of movement of the system 10 along the longitudinal extension of the pipe 20.

[0072] According to one embodiment, the wheel and the fulcrum of the mobility subassembly 14, 14', 14" includes an elastic return mechanism, for example a spring, associated with the wheel configured to keep the wheel in contact with the point of the inner wall section of the pipe 20, as can be seen in Figure 3.

[0073] According to one embodiment, the shuttering system 10 comprises several mobility sub-assemblies 14, 14', 14" offset from one another in the direction of the longitudinal extension of the system 10, and distributed respectively on the transport sub-system 11, and on the shuttering device 12. In particular, the mobility sub-assemblies 14, 14', 14" are distributed along the transport sub-system 11, on the different devices or modules that constitute the transport sub-system 11. Thus, the mobility of the different sub-systems, devices, components or modules 11, 12, 17 of the system 10 is ensured with good mechanical stability. In particular, according to one example embodiment, the linking component 17 is equipped with a mobility sub-assembly 14', mounted for example on an end part 18 of the linking component 17 (this example embodiment is shown in Figures 2, 6, 6a, and 6b).Thus, when the system 10 is in CLS release configuration, the linking component 17 is held in the desired direction to facilitate the transition of the system 10 from the CLS release configuration, in which the linking component 17 of the transport subsystem 11 is free, as illustrated in Figure 6b, to the CTS transport configuration in which the linking component 17 joins the shuttering device 12 to hook the shuttering device 12 to the transport subsystem 11, as illustrated in Figure 6a.

[0074] In Figure 1, the mobility subsets 14, 14' are distributed on the shuttering system 10 with in particular two mobility subsets 14 and 14' distributed on the shuttering device 12; according to another embodiment, shown in Figures 2, 6a and 6b, the shuttering device 12 can be equipped with only one mobility subset 14;Indeed, a minimum mechanical stability of the shutter device 12 is thus ensured, on the one hand in the transport configuration of the CTS system thanks to the mobility sub-assemblies 14, 14', 14" distributed over the other devices, components, or modules of the transport sub-system 11 to which the shutter device 12 is connected, on the other hand in the release configuration of the CLS system thanks to the retention sub-assembly 16 of the shutter device 12 in the mechanical retention configuration CMM which will be described later, and which cooperates with the mobility sub-assembly 14 of the shutter device 12 to ensure the stability of the shutter device 12 in the release configuration of the CLS system.

[0075] The sealing device 12 includes a sealing sub-assembly 15, for example an inflatable component 15, for example an inflatable elastic membrane 15, configured to transition from a COB sealing configuration in which the sealing sub-assembly 15 provides a watertight seal of the pipe 20 at a sealing point PO of the pipe 20, the seal being watertight to a fluid flowing in the pipe at the sealing point PO of the pipe 20, to a COU opening configuration in which the sealing sub-assembly 15 does not provide a watertight seal of the pipe 20. The term "sealing point" PO here simply designates a position along an axis of the pipe 20 of a central point PO of a cross-section relative to the axis of the pipe, the seal being ensured over the entire said cross-section centered on said central point PO.The fluid against which the seal is ensured can be, for example, a gas, a liquid, or even a dust aerosol.

[0076] The inflatable component 15 is for example arranged around the sealing device 12, transverse to the longitudinal extension of the system 10 and the pipe 20, the inflatable component 15 being deflated in the opening configuration COU of the sealing sub-assembly 15, the inflatable component 15 being further configured to ensure, in the inflated state, in the sealing configuration COB of the sealing sub-assembly 15, a first watertight contact with the inner wall of the pipe at the sealing point PO and a second watertight contact with the sealing device 12, so that in the inflated state of the inflatable component 15, the pipe is hermetically sealed by the sealing device 12.

[0077] The sealing device 12 further includes a holding sub-assembly 16 configured to move from a mechanical CMM holding configuration in which the holding sub-assembly 16 provides mechanical holding of the sealing device 12 against the inner wall of the pipe 20, to a free CLM configuration in which the sealing device 12 is not held by the holding sub-assembly 16.

[0078] The retaining subassembly 16 includes, for example, at least two retaining components 16, sometimes called clamps 16, configured to be deployed in the mechanical retaining configuration CMM, the retaining components being deployed transversely to the longitudinal extension of the pipe 20 to bear on different points of a section of the inner wall of the pipe 20, as illustrated in Figure 4, or in Figure 6b.

[0079] Thus, when the inflatable component 15 of the sealing device 12 is deflated, accidentally for example, after having been inflated in the COB sealing configuration of the sealing subassembly 15, the sealing device remains mechanically held against the pipe wall 20 by the holding subassembly 16 deployed in the CMM mechanical holding configuration.

[0080] In one embodiment, at least two retaining components 16 are retracted by a single-acting cylinder and extended by a spring. In other words, the spring presses on the retaining component 16 to extend it into its mechanically held configuration, and the cylinder retracts the retaining component 16 to return it to its free configuration. In one embodiment, the cylinder is pneumatic.

[0081] According to an exemplary embodiment illustrated in Figure 8, the retaining components 16 each comprise a unidirectional rolling component 21. The unidirectional rolling component 21 is configured to allow mobility in only one direction along the longitudinal extension of the pipeline 20, while mobility is locked in the opposite direction. For this purpose, the unidirectional rolling component 21 may include a polyurethane wheel providing good traction, the rim of which is formed by a unidirectional bearing. Advantageously, the only direction of mobility is oriented from the sealing device 12 towards the transport subsystem 11.Thus, the sealing device 12 is not at risk of detaching from the wall in the opposite direction to the arrival direction of the transport subsystem 11, when the transport subsystem 11 approaches the sealing device 12 to load and retrieve it in the CTS transport configuration of the system 10. Also, in the event of a leak in the air circuit of the cylinders configured to allow the passage to the CLM free configuration of the holding subassembly 16, the sealing device 12 can be pulled towards the exit even when the holding subassembly 16 is blocked in the CLM holding configuration.

[0082] According to a particular embodiment, the dimensions of the shuttering system 10 are defined on the basis of a virtual geometric envelope defined to virtually enclose each elementary module 13, 13', 13" and the shuttering device 12 composing the system 10 in the transport configuration of the CTS system, without taking into account the mobility sub-assemblies 14, 14', 14" that may be mounted on the different elementary modules 13, 13', 13" and the shuttering device 12 of the system 10. Said virtual geometric envelope has, for each elementary module, a transverse dimension D, D', for example a diameter D, D', measured in a plane transverse to the longitudinal extension of the system 10, and a longitudinal dimension L, L' measured along a longitudinal extension of the system 10, for example a length L, L', as shown in Figure 7.The longitudinal dimension L, L' is determined as a function of the transverse dimension D, D', and at least one dimension of a bend in the pipeline, to allow each elementary module 13, 13', 13" and the sealing device 12 of the system 10 in CTS transport configuration to pass through said bend in the pipeline 20.

[0083] For example, at least one dimension of a pipe bend is a radius of curvature RC of a central axis of the pipe at the bend considered and an inside diameter Dint of a section of the pipe 20. The radius of curvature RC is defined geometrically as half the sum of an external radius of curvature RCE, or radius of the extrados inside the bend, and an internal radius of curvature RCI, or radius of the intrados inside, at the bend considered, as illustrated in Figure 7.

[0084] More specifically, the function can be written, for example:

[0085] [Math 1]

[0086] L=Sin(Arcos((D+RC-Dint / 2) / (RC+Dint / 2)))*2*(RC+Dint / 2).

[0087] Thus, the sealing system 10, composed of elementary modules 13, 13', 13”, and a sealing device 12, each being circumscribed, without the mobility subsets 14, 14', 14”, within a virtual geometric envelope defined by a diameter D and a length L, is capable of moving within a pipe 20 comprising one or more bends whose average radius of curvature is greater than or equal to RC and whose internal diameter is greater than or equal to Dint.

[0088] According to these provisions, the sealing system 10 is capable, thanks to the particular dimensioning described above of the elementary modules 13, 13', 13”, and of the sealing device 12 which make up said sealing system 10, as well as thanks to the flexibility of the linking components 17 which connect the elementary modules 13, 13', 13”, and the sealing device 12 which make up said sealing system 10, and also thanks to the distribution of the support and rolling points inside the pipeline, of moving inside a pipeline even if the pipeline 20 has bends and even if some portions of the pipeline 20 are not horizontal; The shuttering system 10 is also capable, thanks to the mechanical support sub-assembly, of depositing the shuttering device 12 at a shuttering point, without the shuttering device risking detachment if the shuttering sub-assembly 15 were to fail.

[0089] When the system 10 is in CTS transport configuration, and the sealing sub-assembly 15 is in COU opening configuration, and the holding sub-assembly 16 is in CLM free configuration, the system is configured to transport the sealing device 12 from one point to another point in the pipeline 20, in both directions of the longitudinal extension direction of the pipeline 20.

[0090] When the sealing sub-assembly 15 is in the opening configuration COU, and simultaneously the holding sub-assembly 16 is in the mechanical holding configuration CMM, the system 10 in the transport configuration CTS is configured to transport the sealing device 12 from one point to another point in the pipeline 20, in only one direction of the longitudinal extension direction of the pipeline 20, movement in the other direction being made impossible by the mechanical holding sub-assembly;a transition from a CLS release configuration of the system to a CTS transport configuration of the system is thus facilitated, by allowing the transport subsystem 11 of the system in CLS release configuration to take support from the sealing device 12 to move the system 10 into the CTS transport configuration, while simultaneously preventing the sealing device 12 from detaching from the wall of the pipe 20 in a direction opposite to the transport subsystem 11 during the transition of the system 10 from the CLS release configuration to the CTS transport configuration.;

[0091] The retaining sub-assembly 16 can take the mechanical retaining configuration CMM when the sealing sub-assembly 15 is in the sealing configuration COB, as schematically illustrated in Figure 6b, or when the sealing sub-assembly 15 is, for example accidentally, in the opening configuration COU, to prevent in the latter case the sealing device 12 from detaching from the wall of the pipe 20.

[0092] According to a particular embodiment, the transport subsystem 11 of the sealing system 10 comprises an elementary module 13 which is an inerting device 13; said inerting device 13 comprises a sealing subset 15 and an inerting subset 13; the sealing subset 15 of the inerting device 13 is configured to switch, when the system 10 is in the CLS release configuration of the system, from a COU opening configuration (not shown in Figure 6b), to a COB sealing configuration as shown in Figure 6b in which the sealing subset 15 of the inerting device 13 ensures a tight sealing of the pipe 20 at another sealing point of the pipe 20; the inerting sub-assembly 13 is further configured to inject an inert gas into the portion of the pipeline between the sealing point PO and the other sealing point.

[0093] Thus, the sealed zone of the pipeline 20 created between the two sealing points is inertized by the mixing of the inert gas with the gas previously existing in this same zone.

[0094] According to one embodiment, the inerting sub-assembly includes a purge to purge at least part of the gas existing in the portion of the pipeline between the sealing point PO and the other sealing point before the injection of the inert gas, in order to maintain a pressure equal to a set pressure, for example atmospheric.

[0095] In one embodiment, the inert gas is denser than the existing gas. The sealing device 12 includes another purge, the purge of the inerting device 13 being closed and the other purge being open to purge at least a portion of the gas present in the portion of the pipeline between the sealing point PO and the other sealing point before the injection of the inert gas, when an altitude of the purge of the inerting device 13 is lower than an altitude of the other purge; or conversely, the purge of the inerting device 13 is open and the other purge of the sealing device 12 is closed to purge a portion of the gas present in the portion of the pipeline between the sealing point PO and the other sealing point before the injection of the inert gas, when an altitude of the purge of the inerting device 13 is higher than an altitude of the other purge.

[0096] According to a more specific example of implementation, the inerting sub-assembly includes lighting and a camera allowing visual inspection of the section of pipe.

[0097] According to an even more specific embodiment, the inerting sub-assembly includes an oxygenometer to validate the oxygen level in the sealed portion of the pipeline.

[0098] According to one embodiment, the linking component 17 is configured to allow the passage from the transport subsystem 11 to the sealing device 12 of an inflation circuit of the inflatable component of the sealing subassembly 15 of the sealing device 12 and / or of an activation circuit of a pneumatic cylinder 16 of at least two retaining components 16 of the sealing device 12 and / or of a power supply circuit of the sealing device 12. According to one embodiment, the inflation circuit of the inflatable component of the sealing device and the activation circuit of a pneumatic cylinder of at least two retaining components of the sealing device are coupled such that the retraction of the pneumatic cylinder of at least two retaining components activates a deflation of the inflatable component.

[0099] According to one aspect of the invention, it relates to a method of sealing and / or inerting a pipeline of a nuclear power plant using a sealing system 10 according to one of the embodiment examples described above.

Claims

DEMANDS 1. Pipeline (20) sealing system (10) comprising a transport subsystem (11) and a sealing device (12), the transport subsystem (11) being motorized, configured to move inside the pipe (20) in the direction of a longitudinal extension of the pipe (20), the system (10) further being configured to alternately and reversibly switch from a transport configuration (CTS) of the system in which the sealing device (12) is connected to the transport subsystem (11) by a flexible linking component (17), to a release configuration (CLS) of the system in which the sealing device (12) is detached from the transport subsystem (11), the system (10) further comprising at least one mobility sub-assembly (14, 14', 14") configured to be mounted on the transport sub-system (11) and on the sealing device (12) and deployed transversely to the longitudinal extension of the pipeline (20) such that the at least one mobility sub-assembly (14, 14', 14") is supported on at least two support points distributed over a section of an inner wall of the pipeline (20) when deployed, so that the system (10) is mechanically recalled, transversely to the longitudinal extension of the pipeline (20), towards a central area of ​​the section of the pipeline (20), while simultaneously ensuring longitudinal mobility of the system (10) in the direction of the longitudinal extension of the pipeline (20); the sealing device (12) comprising a sealing sub-assembly (15) configured to transition from a sealing configuration (COB) in which the sealing sub-assembly (15) provides a tight seal of the pipe (20) at a sealing point (PO) of the pipe (20), the sealing being tight against a fluid flowing in the pipe at the sealing point (PO) of the pipe (20), to an opening configuration (COU) in which the sealing sub-assembly (15) does not provide a tight seal of the pipe (20); the sealing device (12) further comprising a holding sub-assembly (16) configured to move from a mechanical holding configuration (CMM) in which the holding sub-assembly (16) provides mechanical holding of the sealing device (12) against the inner wall of the pipe (20), to a free configuration (CLM) in which the sealing device (12) is not held by the holding sub-assembly (16).

2. A system (10) according to claim 1, wherein the transport subsystem (11) comprises an elementary module (13) connected by the flexible link component (17) to the closing device (12), or comprises an elementary module (13) connected by the flexible link component (17) to the closing device (12) and connected, directly or indirectly, by another flexible link component (17') to at least one other elementary module (13', 13”), the at least one other elementary module (13', 13”) and the elementary module (13) and the closing device (12) each being circumscribed within a virtual geometric envelope having a transverse dimension (D, D') measured in a plane transverse to the longitudinal extension of the system (10), and a longitudinal dimension (L, L') measured along a longitudinal extension of the system (10), the longitudinal dimension (L, L') being determined as a function of the transverse dimension (D, D'),and at least one dimension of a pipe bend to allow the system (10) in transport configuration (CTS) to pass through the pipe bend.

3. System (10) according to any one of claims 1 or 2, wherein each support point of at least two support points of at least one mobility subset (14, 14') comprises a wheel bearing against the inner wall of the pipeline.

4. System (10) according to claim 3, wherein at least one mobility subset (14, 14') further comprises at least one elastic return mechanism, for example a spring, associated with the wheel configured to keep the wheel in contact with the point on the inner wall of the pipe.

5. System (10) according to any one of the preceding claims, wherein the sealing subassembly (15) comprises an inflatable component (15) disposed around the sealing device (12), transverse to the longitudinal extension of the system (10) and the pipeline (20), the inflatable component (15) being deflated in the open configuration of the sealing subassembly, the inflatable component (15) further being configured to ensure, in the inflated state, in the sealing configuration (COB) of the sealing subassembly (15), a first watertight contact with the inner wall of the pipeline at the sealing point (PO) and a second watertight contact with the sealing device (12), so that in the inflated state of the inflatable component (15), the pipeline is hermetically sealed by the sealing device (12).

6. System according to any one of the preceding claims, wherein the retaining subassembly (16) comprises at least two retaining components (16) configured to be deployed in the mechanical retaining configuration (MRC), the at least two retaining components being deployed transversely to the longitudinal extension of the pipeline (20) to bear on different points of a section of the inner wall of the pipeline (20).

7. System according to claim 6, wherein the at least two retaining components (16) comprise a unidirectional rolling component, the unidirectional rolling component being configured to provide mobility in only one direction of the longitudinal extension direction of the pipeline (20), the mobility being locked in the other direction.

8. System according to claim 7, wherein the only direction of mobility is oriented from the sealing device (12) towards the transport subsystem (11).

9. System according to any one of the preceding claims, wherein the linking component (17) comprises a terminal part (18) configured to cooperate with a complementary element (19) of the sealing device (12).

10. System according to claim 9, wherein the terminal part (18) comprises a camera configured to observe through the shutter device (12) via a transparent wall when the terminal part (18) cooperates with the complementary member (19) of the shutter device (12) to connect the shutter device (12) to the transport subsystem (11).

11. A system (10) according to any one of the preceding claims, wherein the elementary module (13) is an inerting device (13), the inerting device (13) comprising a sealing subassembly (15) and an inerting subassembly (13), the sealing subassembly (15) of the inerting device (13) being configured to transition, when the system (10) is in its system release configuration (CLS), from an opening configuration (COU) to a sealing configuration (COB), wherein the sealing subassembly (15) of the inerting device provides a watertight seal of the pipeline (20) at another sealing point of the pipeline (20), the inerting subassembly (13) being configured to inject an inert gas into the portion of the pipeline between the sealing point (PO) and the other point of obturator.

12. System (10) according to any one of the preceding claims, wherein the linking component (17) is configured to permit passage from the transport subsystem (11) to the shuttering device (12) of a circuit of inflation of the inflatable component of the sealing subassembly (15) of the sealing device (12) and / or an activation circuit of a pneumatic cylinder (16) of at least two retaining components (16) of the sealing device (12) and / or an electrical supply circuit of the sealing device (12).

13. Method for sealing and / or inerting a pipeline in a nuclear power plant comprising the use of a system according to one of the preceding claims.