EP2789550B1 - Handling and containment hood, use for handling sample-holders of nuclear materials, such as nuclear fuels - Google Patents

Description

Field of the invention

The present invention relates to a new hood handling and containment of at least two elongated objects.

The main application targeted by the invention is the handling of sample holders of nuclear materials in a nuclear research reactor, allowing the introduction and extraction of the sample holders without breaking the confinement with respect to the outside atmosphere.

Although described below with reference to the main application, the invention also applies to any application in which it is necessary to carry out the handling and confinement of elongated objects, in particular in constraining environments. terms of congestion and security.

For conciseness purposes, throughout the present application, a sample tube may be referred to as "PE tube", and a "PI tube" instrumentation tube.

Throughout the present application, the terms "lower", "upper", "vertical", "rise", "descent", "below" and "above" are to be understood by reference to a handling by the organ gripping from the top of the upper end of an object to handle and to confine in a hood. Thus, during handling and containment for gripping an elongate object and its introduction into the hood, the gripping member performs a descent and a recovery.

State of the art

To test the behavior of materials and fuels subject to thermal, neutron or even chemical stresses representative of full-scale operation in an industrial nuclear reactor, it is common practice to use research reactors, indispensable tools in research and development. of the nuclear power industry.

These nuclear research reactors are also commonly called irradiation reactors because they make it possible to perform irradiation experiments of samples of nuclear materials, such as nuclear fuels, in the pool near or in the reactor core.

In particular, the research reactor that will soon be commissioned in France, the Jules Horowitz reactor (RJH) will be used to study the behavior of nuclear fuels under different irradiation scenarios.

In order to carry out the irradiation experiments in the irradiation reactors, irradiation devices are specifically designed as a function, in particular, of their dedicated location in the core and or near it in a concentration zone of an irradiating flux.

In the RJH reactor, there is provided an irradiation device designed particularly for the study of nuclear fuel and sheath materials of rods housing the nuclear fuel.

To ensure the handling of nuclear material samples in nuclear research reactors, it is known to use as a sample holder a tube inside which is housed a sample such as a column of nuclear fuel pellets.

More specifically, a sample tube (PE tube) comprises several tubular portions of different section including the enlarged portion of the upper portion, hereinafter referred to as the gripping head, by which the gripping of the PE tube is carried out for its handling. The sample to be irradiated is in turn arranged in a portion of the PE tube remote from the gripping head, preferably opposite to it, especially when the sample is a column of irradiating fuel pellets. In the installed irradiation configuration within or near the core, the portion of the PE tube in which the sample is housed must be arranged in an area subject to the neutron flux, under the conditions required by the irradiation experiment (T °, middle ...).

To ensure the measurements of the physical parameters related to the samples, it is planned to introduce the PE tube in a concentric blind tube, hereinafter referred to as instrumentation tube (PI tube), inside which are housed in particular sensors of measurement and a cooling system. A PI tube is stowed to a part of the irradiation device.

In addition, to meet the safety requirements, it is necessary to ensure a seal between the PE tube which constitutes the inner tube, and the PI tube, which constitutes the external tube in order to constitute a confinement barrier, because the heat transfer medium of the cooling system circulating between the PI and PE tubes at a high pressure, typically at least 160 bars, must not be able to escape into the pool of the reactor. 'irradiation. In other words, in the installed irradiation configuration, it is necessary to have a tight lock of the PE tube in the PI tube.

Thus, prior to an irradiation experiment, the handling of a PE tube requires its gripping by a gripping member, the descent of the gripping member and the PE tube for the introduction of the latter into a PI tube, mutual interlocking between these two PE and PI tubes and the rise of the gripping member alone.

In the opposite direction, after an irradiation experiment, the handling of a PE tube housed in the tube PI requires the descent of the gripping member, the gripping of the PE tube by the gripping member, the unlocking of the PE tube PI tube and the rise of the gripping member and the PE tube.

Also, to meet the safety requirements, the gripping of the PE tube by the gripping member must be ensured with a locking of the gripping force.

In the field of the handling of nuclear materials or radioactive substances, it is known to use gripper systems (grippers) with clamping force clamps and use hooks to perform the locking / unlocking of containers or drums containing either nuclear material or containers containing radioactive substances themselves. The use of hooks as locking means is often preferred because they are a reliable and simple solution to achieve, including with few mechanical parts.

The applicant has proposed in the patent application filed December 4, 2012 under the number FR 12 61578 , a new system for gripping and locking / unlocking an inner tube in an outer tube concentric to the inner tube, with locking / unlocking the gripping force which is reliable, simple to achieve with a limited number of parts, and fast to implement. This system is particularly suitable for gripping a PE tube and sealing / unlocking the PE tube in a PI tube within a nuclear irradiation reactor. More specifically, the new system consists essentially of one or a plurality of attachment devices that allow (ent) both the sealing / unlocking of the PE tube to the gripping member before and after the irradiation experiments in the irradiation reactor, and the PE tube in the PI tube for the realization of these experiments, and this with only a displacement in translation of a gripping member according to a stroke A or a stroke B slightly greater than the race A.

In order to be able to grip an irradiated PE tube and to phase in a PI tube a new PE tube, using this new gripping and locking / unlocking system, without disconnecting the electrical and fluidic power supplies and while ensuring the continuity of the confinement barriers required, the inventors were then confronted with the need to find a hood that integrates both the translational movement means of the gripping member of said system and the tube confinement means PE and can be used reliably under water in a reactor pool.

Various leaktight hoods for the replacement of irradiated equipment and the transport of such equipment to an unloading unit where they can undergo the appropriate treatments or repairs have already been implemented in a nuclear environment.

Here we can mention the patent application FR 2 544 542 which discloses a mobile containment chamber for the replacement and transport of contaminated parts, with a sealed shielded body inside which is disposed a barrel with three cylindrical cells able to receive respectively a new part, a contaminated part and an instrument observation or control, either another gripping head of a plug giving access to the part to be evacuated, or an intervention tool. This movable enclosure further comprises manual mechanical means for rotating the barrel inside the body so as to bring each cell in turn facing an opening of the same diameter formed in the body, a gripping head slidably mounted in each cell via a rack-and-pinion, means for manually moving the head, arranged outside the shielded body, and allowing movement between a rear storage position of the parts and a pre-intervention position in which the gripping head enters said opening.

The mobile enclosure disclosed according to this application FR 2 544 542 has the advantage of reliably ensuring the replacement of contaminated parts with new ones without breaking the confinement.

However, such a movable enclosure does not allow the gripping and confinement of objects of slender shape, that is to say with a very large length compared to other dimensions, such as a PE tube, with a system according to Requirement FR 12 61578 , in a small space, for a submerged watertight use, in particular under water in a reactor, and with a high rate for the following reasons.

Indeed, the grapple used in the mobile enclosure according to the application FR 2 544 542 above, slides outside the shielded body and its sealing is provided by a metal bellows. However, in the case of objects of slender shape, such as PE tubes, the strokes necessary for their gripping and their confinement in a hood that is desired to reduce space does not allow to consider a seal with a metal bellows of makes his crush game necessary. Thus, sealing on a stroke equal to a length of a PE tube of the order of 3.5 m with a metal gusset crush usual play of the order of 10% of its length would necessarily create a pregnant according to demand FR 2 544 542 above a height of 35m, which is incompatible with a requirement of reduced size.

Furthermore, the actuation of the gripping member of the system according to the application FR 12 61578 requires precise control, maintained over time, races A and B he must achieve. However, the gripping member provided in the mobile enclosure according to the application FR 2 544 542 aforementioned is a conventional grapple and its means of travel is a cogwheel perch, which can not provide this precise control, maintained over time.

Finally, a metal bellows sealing in the mobile enclosure according to the request FR 2 544 542 aforesaid, fatigue and breaks very quickly therefore present a very limited life span with as a corollary complicated maintenance. This is therefore detrimental to a high rate of PE tube change irradiated by a new PE tube.

There is therefore a need to improve the hoods for handling and confining objects of slender shape, in particular to allow their grip with a system according to the patent application FR 12 61578 , in a small space, for a submerged watertight use, in particular under water in a reactor, and with a high rate.

Presentation of the invention

• une première enceinte, dite enceinte externe, s'étendant selon un axe longitudinal X', comportant un couvercle, un fond muni d'une ouverture et une vanne pour obturer l'ouverture et rendre ainsi étanche l'enceinte externe;
• une deuxième enceinte formant barillet, s'étendant selon l'axe X' et guidée en rotation à l'intérieur de l'enceinte externe autour de l'axe X' ;
• au moins une troisième et quatrième enceintes, dites enceintes internes, s'étendant chacune selon un axe longitudinal X1, X2 parallèle à l'axe X' et adaptées chacune pour loger un objet de forme allongée, les au moins deux enceintes internes étant solidaires entre elles et guidées en translation dans le barillet selon une course A0 ;

chaque enceinte interne comportant en son sein :

• un organe de préhension adapté pour saisir un objet de forme allongée;
• un mécanisme vis-écrou constitué d'une vis sans fin guidée en rotation autour de l'axe X1, X2, et d'un écrou autour de la vis et auquel est solidarisé l'organe de préhension, le mécanisme étant adapté pour guider en translation ce dernier dans l'enceinte interne selon une course A supérieure à la course A0;
• un fond muni d'une ouverture en regard de l'organe de préhension pour laisser passer un objet saisi par ce dernier ;

la hotte comportant en outre :

• au moins un moteur fixé au-dessus d'une enceinte interne et à l'intérieur du barillet, le(s) moteur(s) étant adapté(s) pour mettre en rotation la vis du mécanisme vis-écrou de chaque enceinte interne et ainsi l'écrou selon la course A;
• des moyens de commande mécanique, agencés en partie au-dessus du couvercle de l'enceinte externe, pour guider manuellement en translation les enceintes internes selon la course A0;
• des moyens de commande mécanique, agencés en partie au-dessus du couvercle de l'enceinte externe, pour faire pivoter manuellement le barillet afin d'amener un organe de préhension de l'une des enceintes internes en regard de l'ouverture du fond de l'enceinte externe.

The invention aims to meet all or part of these needs and has the object, according to one of its aspects, of a hood for the containment and handling of at least two objects of slender shape comprising:

• a first enclosure, said outer enclosure, extending along a longitudinal axis X ', having a cover, a bottom provided with an opening and a valve for closing the opening and thus sealing the outer enclosure;
• a second barrel-shaped enclosure, extending along the axis X 'and guided in rotation inside the outer enclosure around the axis X';
• at least a third and fourth enclosure, called internal enclosures, each extending along a longitudinal axis X1, X2 parallel to the axis X 'and each adapted to accommodate an elongate object, the at least two internal enclosures being integral between they and guided in translation in the barrel along a stroke A0;

each internal chamber comprising within it:

• a gripping member adapted to grip an elongated object;
• a screw-nut mechanism consisting of a worm guided in rotation about the axis X1, X2, and a nut around the screw and which is secured to the gripping member, the mechanism being adapted to guide in translation of the latter in the inner chamber along a stroke A greater than the stroke A0;
• a bottom provided with an opening facing the gripping member to let pass an object grasped by the latter;

the hood further comprising:

• at least one motor fixed above an inner chamber and inside the barrel, the motor (s) being adapted (s) to rotate the screw of the screw-nut mechanism of each internal enclosure and thus the nut according to the race A;
• mechanical control means, arranged in part above the cover of the outer enclosure, for manually guiding the internal enclosures in translation along the path A0;
• mechanical control means, arranged in part above the cover of the outer enclosure, to manually rotate the barrel to bring a gripping member of one of the internal enclosures facing the opening of the bottom of the the external enclosure.

• autorise un déplacement en translation de l'organe de préhension d'une tube PE et son contrôle précis selon une course A ou une course B légèrement supérieure (B égale à A +A0), dans un encombrement réduit grâce d'une part au(x) moteur(s) et au(x) mécanisme(s) vis/écrou prévus en tant qu'actionneurs de l'organe de préhension et d'autre part aux moyens mécaniques de translation des enceintes internes depuis l'extérieur,
• permet une utilisation immergée étanche du fait de l'enceinte externe étanche et de l'indépendance des enceintes internes respectivement dédiées au confinement d'un tube PE irradié et d'un tube PE neuf, et
• permet d'atteindre une cadence élevée de changement d'un tube PE irradié en un tube PE neuf du fait notamment du barillet intégré.

In other words, the invention essentially consists of a handling and containment hood, which:

• allows a translational movement of the gripping member of a PE tube and its precise control according to a stroke A or a slightly higher stroke B (B equal to A + A0), in a reduced bulk thanks firstly to ( x) motor (s) and screw / nut mechanism (s) provided as actuators of the gripping member and secondly to the mechanical means of translation of the internal enclosures from the outside,
• allows a submerged watertight use due to the sealed external enclosure and the independence of the internal enclosures respectively dedicated to the confinement of an irradiated PE tube and a new PE tube, and
• makes it possible to achieve a high rate of change from an irradiated PE tube to a new PE tube, in particular because of the integrated barrel.

The hood according to the invention is particularly advantageous because it is simple to perform, reliable and quick to implement.

It allows with a system according to the patent application FR 12 61578 , reliable handling of blind samples of materials, ie in a configuration where it is not possible to verify visually or by any other technological means, such as a camera, the locked state or not elements. The motor (s) and mechanism (s) screw / nut of each internal chamber in fact make it possible to control the stroke reached A or not by the gripping member to and in the PE tube. The manual guiding means in translation of the internal enclosures according to the stroke A0 allow precise control of the stroke B, equal to A + A0.

According to an advantageous embodiment, the hood further comprises a fifth enclosure, said internal enclosure, also extending along a longitudinal axis X3 parallel to the axis X 'and adapted to accommodate an elongated object, the three internal enclosures integral with each other being distributed at 120 ° to one another inside the barrel. There is thus an additional object housing to handle and to confine in the hood, such as a PE tube.

According to an advantageous embodiment, the closure valve of the bottom opening of the outer enclosure is a guillotine type valve. With such a valve, it reduces the size of the hood.

According to an advantageous embodiment, the hood further comprises a metal bellows fixed below each internal enclosure opening to ensure the seal between the latter and the opening of the outer enclosure, during the translation of the internal enclosures in the barrel. In other words, this bellows seals between the opening of the bottom of the outer enclosure and the opening of the bottom of an inner enclosure during the downward movement thereof.

In order to ensure the seal between the barrel and the outer enclosure, in particular when handling PE pipe under water in the reactor pool, the hood preferably comprises at least two O-rings housed each at least partly in a peripheral groove respectively at the top and at the bottom of the outer wall of the barrel.

According to an advantageous embodiment, there is provided a motor fixed above each inner chamber and inside the barrel, the motor being adapted to rotate the screw of the screw-nut mechanism of said inner chamber and thus the The nut according to the stroke A. Preferably, the motor (s) is (are) an electric motor (s).

According to an advantageous characteristic, the gripping member is mounted on the nut of the screw-nut mechanism by means of a plate guided against the inner wall of the inner chamber by at least two lugs projecting from the plate and forming centering devices. Thus, a perfect guiding in translation of the gripping member inside the internal enclosure without any risk of jamming

According to an advantageous embodiment, the mechanical control means for manually guiding in translation the internal enclosures according to the stroke A0 comprise a screw-nut mechanism consisting of a worm on a portion of a rod guided in rotation around the X 'axis and through the cover, and a nut around the screw and which are secured to the internal enclosures.

Thus, a manual rotation of the rod (pole) from outside the hood allows to translate down the internal speakers inside the barrel. This is advantageous because this mechanical control is simple to perform and reliable. In particular, when a very short stroke A0 must be made compared to the stroke A carried out by a motor actuating the screw-nut mechanism inside the inner chamber, the reliable and reproducible rotation of the rod ensures precise control. , maintained in time, of the race A0. This mechanical control by rotation of the rod is advantageous in an underwater environment in a nuclear reactor pool in which the handling is performed blind or at least whose visualization can not be accurate, safe and reliable. Indeed, in such an environment, there is no reliable visual verification means and therefore the fact of having a command with a precise control of the race A0 from the outside makes it possible to ensure the good realization of it.

By this, it ensures the effective unlocking of a PE tube of the gripping member when implementing the gripping system and locking / unlocking according to the patent application FR 12 61578 whose content is fully contained in this application.

To achieve the race A0, a natural solution for a person skilled in the art could have been to use the same motor and actuator by screw / nut mechanism inside an internal enclosure. In fact, this solution turns out to be practically impossible. Indeed, the implementation would lead to having to implant in addition, within the hood according to the invention, at least three positional electrical sensors to detect the start of race and end of race A and A0. And this is impossible due to lack of space available in the hood that is desired compact and because of the additional difficulty that there would be to change this (s) sensor (s) in case of failure.

According to one embodiment, the mechanical control means for manually rotating the barrel comprise a gear mechanism consisting of a pinion on a portion of a rod guided in rotation parallel to the axis X 'and passing through the lid, and a ring gear meshing internally with the pinion and which is secured to the barrel. A so-called rotary table mechanism is thus produced which is very compact and thus makes it possible to maintain a reduced size of the hood.

Advantageously, the gripping member comprises a gripping head adapted to be housed in an inner tube as an object of elongated shape to be grasped, the inner tube being itself adapted to be fitted into an outer tube. It is thus possible to implement directly a gripping and locking / unlocking of the gripping system the patent application FR 12 61578 .

The invention also relates to the use of the hood which has just been described for the handling and confinement of the inner tube constituting a sample holder tube material, the outer tube constituting a measuring instrumentation holder.

According to this use, the sample tube is intended to house a sample of nuclear materials, such as nuclear fuels, in a tube measuring instrumentation holder for accommodating at least measuring sensors and, where appropriate, a cooling system.

Description Detailed

• la figure 1 est une vue schématique en configuration installée d'irradiation d'un tube porte-échantillon (PE) dans un tube porte-instrumentation (PI) dans un réacteur nucléaire de recherche;
• la figure 2 est une vue schématique en éclaté partiel d'un dispositif d'accrochage relié à un tube intérieur conformément à la demande de brevet FR 12 61578 ;
• la figure 3 est une vue schématique de l'intérieur du tube intérieur montrant un détail du dispositif d'accrochage selon la demande de brevet FR 12 61578 avec le moyen de rappel facultatif de son crochet de verrouillage;
• les figures 4A à 4J sont des vues en perspective et en coupe montrant les différentes étapes de préhension du tube intérieur par l'organe de préhension simultanément avec le déverrouillage entre tubes intérieur et extérieur selon la demande de brevet FR 12 61578 ;
• les figures 5A à 5J sont des vues en perspective et en coupe montrant les différentes étapes de libération du tube intérieur de l'organe de préhension simultanément avec le verrouillage entre tubes intérieur et extérieur selon la demande de brevet FR 1261578 ;
• la figure 6 est une vue de dessus de la hotte de manutention et de confinement selon l'invention ;
• la figure 6A est une vue en coupe longitudinale partielle de la hotte de la figure 6 selon A-A ;
• la figure 6B est une vue en coupe transversale la hotte de la figure 6 selon B-B ;
• la figure 6A est une vue en coupe longitudinale de la hotte de la figure 6 selon A-A ;
• les figures 6C et 6D sont des vues en coupe longitudinale de la hotte de la figure 6 selon respectivement C-C et D-D;
• les figures 6E, 6F et 6H sont des vues en coupe transversale de la hotte de la figure 6 selon respectivement E-E, F-F et H-H ;
• la figure 7 est une vue de dessous de la hotte de manutention et de confinement selon l'invention ;
• la figure 8 est une vue en coupe longitudinale partielle d'une enceinte interne de la hotte de la figure 6;
• la figure 9 est une vue en coupe longitudinale et en perspective partielle de la hotte de la figure 6;
• les figures 9A et 9B sont des vues de détail de la figure 9.

Other advantages and characteristics of the invention will emerge more clearly on reading the detailed description of exemplary embodiments of the invention, given by way of nonlimiting illustration and with reference to the following figures among which:

• the figure 1 is a schematic view in the installed configuration of irradiating a sample tube (PE) in an instrumentation tube (PI) in a nuclear research reactor;
• the figure 2 is a schematic partial exploded view of an attachment device connected to an inner tube according to the patent application FR 12 61578 ;
• the figure 3 is a schematic view of the inside of the inner tube showing a detail of the fastening device according to the patent application FR 12 61578 with the optional return means of its locking hook;
• the Figures 4A to 4J are views in perspective and in section showing the different steps of gripping the inner tube by the gripping member simultaneously with the unlocking between inner and outer tubes according to the patent application FR 12 61578 ;
• the Figures 5A to 5J are views in perspective and in section showing the different steps of release of the inner tube of the gripping member simultaneously with the locking between inner and outer tubes according to the patent application FR 1261578 ;
• the figure 6 is a top view of the handling and containment hood according to the invention;
• the Figure 6A is a partial longitudinal sectional view of the hood of the figure 6 according to AA;
• the Figure 6B is a cross-sectional view the hood of the figure 6 according to BB;
• the Figure 6A is a longitudinal sectional view of the hood of the figure 6 according to AA;
• the Figures 6C and 6D are views in longitudinal section of the hood of the figure 6 according to CC and DD, respectively;
• the Figures 6E, 6F and 6H are cross-sectional views of the hood of the figure 6 according to EE, FF and HH respectively;
• the figure 7 is a bottom view of the handling and containment hood according to the invention;
• the figure 8 is a partial longitudinal sectional view of an internal enclosure of the hood of the figure 6 ;
• the figure 9 is a longitudinal sectional view and partial perspective of the hood of the figure 6 ;
• the Figures 9A and 9B are detailed views of the figure 9 .

We have shown in figure 1 , an inner tube 1, 10 of longitudinal axis X constituting a sample tube intended to house a sample of nuclear materials, such as nuclear fuels, such that it must be locked in an outer tube 2 constituting an instrumentation holder measuring device for housing measuring sensors and a cooling system for irradiation experiments in a water pool 3 of a nuclear research reactor.

More specifically, the inner tube 1 comprises a tubular lower portion in which is housed a sample of nuclear materials, such as a column of nuclear fuel pellets, and a tubular upper portion 10 through which the gripping by a gripping member 6 is performed.

Before any irradiation experiment, the inner tube 1 must be able to be brought into being introduced into the outer tube 2 by the descent of a gripping member and then locked to the outer tube 2, the gripping member to be released from the inner tube 1 in order to be reassembled.

After one or more irradiation experiments, the inner tube 1 must be unlockable from the inside of the outer tube 2 in which it is housed, the gripping member must be able to grip the inner tube 1 unlocked and back with it for extract it from the pool 3.

According to the patent application FR 12 61578 , there is provided a new system of gripping and locking / unlocking which reproduces here the embodiment of Figures 2 to 5I . The system with at least one attachment device 4 is provided to achieve on the one hand the release of the inner tube 1 by the gripping member 6 and in the same movement of the gripping member 6, the tight locking of the tube inside 1 to the outer tube 2 and on the other hand, the unlocking of the inner tube 1 housed in the outer tube 2 and in the same movement of the gripping member 6, gripping the inner tube 1 by the gripping member 6.

The outer tube 2 and the gripping member 6 each comprise a groove 20, 60 respectively. The inner tube 1, 10 comprises at least one notch 11 at its upper end 10a. The gripping head of the gripping member 6 has an outer diameter fitted to the inner diameter of the inner tube 1.

An attachment device 4 according to the patent application FR 12 61578 , is connected to the upper end 10a of the inner tube 10. The attachment device is constituted by a double hook 40, 41, one of which is pivotally mounted about an axis 42, Y1 orthogonal to the longitudinal axis X of the inner tube. As shown in Figures 2 and 3 this axis 42 can be mounted in two lugs 12 spaced from each other, themselves fixed on the upper end 10a of the inner tube 1, 10. The two lugs can be made in one piece with the inner tube 1, 10.

More specifically, the attachment device 4 comprises firstly a locking hook 40 pivoted about the axis 42, Y1 orthogonal to the longitudinal axis X of the inner tube, between a locking position in which it is housed in the groove 20 of the outer tube 2 to ensure the locking of the latter with the inner tube 1, and an unlocking position in which it is remote from said groove 20.

The attachment device 4 also comprises a gripping hook 41 pivotally mounted on the locking hook around an axis 43, Y2 also orthogonal to the longitudinal axis X of the inner tube 1, between a gripping position in which it is housed in the groove 60 of the gripping head 6 to grip the inner tube and at least one release position in which it is remote from said groove 60.

The attachment device 4 also comprises an actuating lever 44 mounted on the axis Y1 for pivoting the locking hook 40 between a first neutral position in which it is distant from the notch and does not protrude from the inside the inner tube 1 and a second neutral position in which it is housed in the notch 11, passing through an actuating position in which it projects inside the inner tube 1. The actuating lever 44 is rotatably connected to the locking hook 40 between its actuating position and its second neutral position and free to rotate by relative to the latching hook 40 between its first and second neutral positions, as explained later with reference to the Figures 4A to 4I . As illustrated in all the figures, the actuating lever may consist of a simple lug 44 in the extension of the locking hook 40.

The gripping and locking / unlocking system according to the patent application FR 12 61578 , finally comprises an elastic return means 5 for returning the gripping hook 41 from a release position to its gripping position. As illustrated in figure 6 , the elastic return means may advantageously consist of a torsion spring with turns 5 mounted around the axis 43, Y2 of pivoting of the gripping hook 41 with its two fixed end turns and a central turn 50 shaped support to bear against the gripping hook 41.

The system according to the patent application FR 12 61578 may further comprise an additional elastic return means 7 for returning the locking hook 40 from its unlocking position to its locking position.

In the illustrated embodiment of the FIGS. 4A to 5I , the system according to the patent application FR 12 61578 comprises three attachment devices 4 such as that described, arranged at 120 ° to each other with respect to the longitudinal axis (X) of the inner tube 2. Such a mode is advantageous because it allows an isostatic distribution of grasping and locking efforts. In this same embodiment, the grooves 20, 60 respectively of the outer tube 2 and the gripping member 6 are each formed on the entire periphery of these deniers.

It is specified here that the arrows D indicate a descent of the gripping member 6, while the arrows R indicate a rise of the gripping member 6.

It is also specified that the stroke A designates the stroke reached by the gripping member 6 at the end of the descent during gripping of the inner tube 1 locked to the outer tube 2 ( Figures 4A to 4J ).

The stroke B designates the stroke reached by the gripping member 6 at the end of the descent during the release of the inner tube 1 and the locking of the latter to the outer tube 2 ( Figures 5A to 5J ).

We now describe the kinematics of the gripping of the inner tube 1 by the gripping member 6 and in the same movement of the gripping member 6, the unlocking between inner tubes 1 and outer 2 that the configuration of the system according to the invention allows.

When the inner and outer tubes 1 and 2 are mutually locked by the locking hook 40 and it is desired to extract the inner tube 1, the gripping member is lowered ( Figures 4A and 4B ).

During its descent, when the gripping member 6 abuts against the operating lever 44, the latter pivots and the locking hook 40, rotatably connected to the lever 44, pivots simultaneously about the axis Y1 to the inside the tubes 1, 2 from its locking position to its unlocking position ( Figure 4C-4D ). Due to its contact with the outer surface of the gripping head, the gripping hook 41 pivots at an angle of a few degrees to the outside of the tubes.

Continuing the descent of the gripping member 6, which causes the housing of the actuating lever 44 to be in its neutral position in the notch 11 and simultaneously the complete release of the locking hook 40 of the groove 20 of the outer tube 2 , that is to say in an unlocking position ( figure 4E ). The unlocking of the inner tube 1 of the outer tube is effectively achieved. In this position, the gripping hook 41 begins to pivot towards the groove 60 of the gripping member 6 under the effect of its own weight and the torsion spring 5 which brings back said hook 41 towards the inside of the tubes 1, 2.

The descent of the gripping member is then interrupted at the end of travel A, the gripping hook 41 continuing to pivot towards the inside of the tube 1 towards its gripping position ( figure 4F ).

We can then start the raising of the gripping member 6, the pivoting of the gripping hook 41 continuing until it has penetrated the groove 60 of the gripping member 6, that is to say reaches his gripping position ( figure 4G ). The gripping and locking of the inner tube 1 to the gripping member 6 are then effectively performed, and the unlocking of the inner tube 1 relative to the outer tube 2 is also achieved. Thus, when gripping the inner tube, the operator is insured against the risk of damage to the gripping system, the inner tube itself or the connection between the two. This point is particularly important when the operations are performed blind or remotely, for example through a slab or an opaque cover, as will be the case in the RJH irradiation reactor. The management of the two races A and B, for example by integrating them in an automatism, makes it possible to ensure the safety of these operations.

The rise of the gripping member 6 is then continued ( Figures 4H to 4J ). The gripping member and the attachment device (s) 4 are sized to overcome the frictional forces of the seal (s) 8 housed inside grooves 80 at the periphery of the inner tube 1 during the extraction of the latter from the outer tube 2 ( figure 4J ).

We now describe the kinematics of the tight locking of the inner tube 1 in the outer tube 2 and in the same movement of the gripping member 6, the release of the inner tube 1 of the latter as the configuration of the system according to the patent application. FR 12 61578 allows.

When the inner tube 1 is gripped by the gripping member and locked to the latter by the gripping hook 41 in its gripping position and that it is desired to lock the inner tube 1 to the outer tube 2, the lower part is lowered. gripping member 6 ( Figures 5A and 5B ). The gripping member 6 and the attachment device (s) 4 are sized to overcome the frictional forces of the seal (s) 8 housed inside grooves 80 at the periphery of the inner tube. 1 when introducing the latter into the outer tube 2 ( Figure 5A ).

Once, the introduction of the inner tube 1 into the outer tube 2 started, we continue the descent of the gripping member 6 ( Figure 5C ), until the abutment of the inner tube 1 is figure 5D ). In this position, the upper end 10a of the inner tube 1 is at the level of that of the outer tube 2.

Continuing the descent of the gripping member, which causes the release of the gripping hook 41 of the groove 60 of the gripping member 6 (FIG. Figure 5 E) .

The descent of the gripping member 6 is continued until the stroke B greater than the stroke A is reached ( figure 5F ). In this position, the actuating lever 44 is no longer maintained in its neutral position in the notch 11 by the release member 6.

The locking hook 40 then pivots around the axis Y1 under the effect of its own weight and the torsion spring 7 towards the outside of the tubes 1, 2, which simultaneously causes the pivoting of the actuating lever 44 in rotation with the hook of locking 40 and also the pivoting of the gripping hook 41 to its release position maintained by the torsion spring 5. The pivoting of the locking hook 40 continues until it has reached its locking position ( figure 5G ). In this position, the effective locking between inner 1 and outer 2 pipes is effectively achieved by the locking hook 40.

A raising of the gripping member 6 is then performed, which causes the actuating lever 44 to pivot upwards from its actuating position ( figure 5G ) to its neutral position ( figure 5H ) in which it does not protrude inside the inner tube 1 ( figure 5I ).

The raising of the gripping member 6 can then continue, the actuating lever 44 pivoting downwards under its own weight until it returns to its initial actuating position ( figure 5I ).

To ensure, on the one hand, the conditioning of new and irradiated PE tubes 1 without breaking the required containment barriers in the reactor pool, and on the other hand the gripping of a PE tube and its locking / unlocking to a PI 2 tube with a precise control, maintained over time, races A and B, is provided according to the invention a hood 8 which is now described with reference to Figures 6 to 9B .

The hood 8 of handling and packaging according to the invention firstly comprises an external enclosure 80 which extends along a longitudinal axis X ', having a cover 800, a bottom 801 provided with an opening 802 and a valve 803 for close the opening and seal the external enclosure.

Inside the outer enclosure 80, a second chamber 81 forming barrel, also extending along the axis X 'is guided in rotation about this axis X'. In order to prevent the water from the reactor pool from entering the space between the outer enclosure 80 and cylinder 81, two O-rings 13 are advantageously provided, each housing at least partly in a peripheral groove 14 respectively at the top. and at the bottom of the outer wall of the barrel 81, as best illustrated in the detail figures 9A and 9B.

Three identical internal enclosures 82A, 82B, 82C, integral with each other, extend each along a longitudinal axis X1, X2, X3 parallel to the axis X '. They are distributed at 120 ° to each other inside the barrel 81. They are each adapted to house a PE tube and are guided in translation in the barrel along a stroke A0. The race A0 is very weak compared to the race A and makes it possible to complete this one to perform the aforementioned race B. In other words, the race B is equal to the race A to which is added the race A0.

Each of these three internal enclosures 82A, 82B, 82C comprises within it a gripping member 6 with a groove 60 adapted for gripping and locking a PE tube as described above with reference to FIGS. Figures 2 to 5J .

They also each comprise a screw-nut mechanism 9A, 9B, 9C consisting of a worm 90A, 90B, 90C guided in rotation about the axis X1, X2, X3 and a nut 91A, 91B, 91C around of the screw and which is secured to the gripping member 6. The worm 90A, 90B, 90C is preferably a trapezoidal screw.

As best shown in figure 8 , according to an advantageous mounting variant, the gripping member 6 is mounted on the nut 91A, 91B, 91C of the screw-nut mechanism 9A, 9B, 9C via a plate 92 guided against the inner wall of the inner enclosure by at least two lugs 93 protruding from the plate and forming centering devices. The rotational guidance of the worm 90A, 90B, 90C relative to the corresponding inner chamber 82A, 82B, 82C is provided by bearing systems 94 on either side of the screw. The types of bearing are of course adapted depending in particular on the length of the worm 90A, 90B, 90C, and the load to bear.

Such a screw / nut mechanism is adapted to guide in translation the gripping member 6 in the inner chamber 82A, 82B, 82C according to the stroke A, that is to say over the entire length of the inner enclosure. Typically, for a length of PE tube of the order of 3.5m, the stroke A is equal to this length of 3.5m and the stroke A0 to achieve the release stroke B of the tube PE 1 of the organ grip 6 ( Figures 5F and 5G ) is of the order of 7.5 to 10 mm.

Finally, as better illustrated in figure 8 in relation to the internal enclosure 82A, each internal enclosure 82A comprises a bottom 820A provided with an opening 821A, facing the gripping member 6 to pass a PE tube 1 seized.

To rotate the screw 90A, 90B, 90C of each screw-nut mechanism 9A, 9B, 9C, an electric type motor 83A, 83B, 83C is fixed above each inner housing 82A, 82B, 82C and the inside of the barrel 81. This thus moves the nut 91A, 91B, 91C screwed on it along the stroke A. The coupling between a worm 90A, 90B, 90C and the output shaft of a corresponding motor 82A, 82B, 82C can be insured advantageously by keys and clamping jaws, not shown, provided for transmission shaft.

The hood 8 further comprises mechanical control means 84 arranged partly above the cover 800 of the outer enclosure 80, to manually guide in translation the internal enclosures 82A, 82B, 82C according to the stroke A0. In the embodiment illustrated in Figures 6 to 9B these means comprise a screw-nut mechanism 87 consisting of a worm 870 on a portion of a rod 871 guided in rotation about the axis X 'and passing through the cover 800, and a nut 872 around the screw and which are secured to the internal enclosures 82A, 82B, 82C.

• faire descendre l'organe préhension sur la course A la plus importante par l'intermédiaire d'un mécanisme vis-écrou 9A, 9B, 9C actionné en rotation par un moteur 83A, 83B, 83C logé entre l'enceinte interne 82A, 82B, 82C sur laquelle il est monté et le couvercle 800 de l'enceinte externe 80 ;
• faire descendre l'organe de préhension 6 pour assurer le déverrouillage d'un tube 1 entre la course A et la course B légèrement supérieure par l'intermédiaire d'un mécanisme vis-écrou 87 actionné manuellement en rotation par une tige (perche) 870 depuis l'extérieur de la piscine de réacteur.

Thus, according to the invention there is provided a dual control whose control can be done precisely and maintained over time and which consists in:

• lowering the gripping member to the largest travel A via a screw-nut mechanism 9A, 9B, 9C actuated in rotation by a motor 83A, 83B, 83C housed between the internal enclosure 82A, 82B, 82C on which it is mounted and the cover 800 of the outer enclosure 80;
• lowering the gripping member 6 to unlock a tube 1 between the stroke A and the stroke B slightly higher by means of a screw-nut mechanism 87 actuated manually in rotation by a rod (boom) 870 from outside the reactor pool.

The hood 8 also comprises mechanical control means 85, arranged partly above the cover 800 of the outer enclosure 80, to manually rotate the cylinder 81 to bring a gripping member 6 of one of the speakers internal 82A, 82B, 82C opposite the opening 802 of the bottom 801 of the outer enclosure 80. In the embodiment illustrated in FIGS. Figures 6 to 9B these means 85 comprise a gear mechanism 88 consisting of a pinion 880 on a portion of a rod 881 guided in rotation parallel to the axis X 'and through the cover 800, and a ring gear 882 in meshing internal with the pinion 880 and which is secured to the barrel 81. In other words, a compact mechanism is usually made called turntable at the top of the barrel 81.

At the bottom of opening 821A, 821B, 821C of each internal enclosure 82A, 82B, 82C is arranged between the latter and the external enclosure 80, a metal bellows 86A, 86B, 86C which makes it possible to ensure tightness during displacement in translation of the internal enclosures by the screw-nut mechanism 87 to perform the stroke A0.

In order to be able to move the hood 8 according to the invention within the reactor pool and to extract it from the latter, it is advantageous to provide so-called sling ears 89 welded to the cover 80: it is thus possible to hang slings that allow the introduction and movement inside or the extraction of the pool.

Thus, the hood 8 according to the invention which has just been described makes it possible to carry out the operations of handling and confinement of an irradiated PE tube and its replacement by a new PE tube in a precise manner and without risk of breaking the barriers of containment. This is all the more advantageous when the operations are performed blind, for example through a slab or an opaque lid, as will be the case in the RJH irradiation reactor. The management of the two races A and B, by the double control of the hood 8 whose control can be done precisely and maintained in time, ensures the safety of these operations.

Although described with reference to the handling and containment of PE pipe, hood 8 which has just been described can be used to handle any object of slender shape in environments that offer little space available and in which security constraints are very strict, especially nuclear environments.

The invention is not limited to the examples which have just been described; it is possible in particular to combine with one another characteristics of the illustrated examples within non-illustrated variants.

Claims (13)

1. Hood (8) for confinement and handling of at least two objects of slender shape, including:

   - an external first enclosure (80) extending along a longitudinal axis X', including a cover (800), a bottom (801) provided with an opening (802) and a valve (803) for blocking the opening and thereby sealing the external enclosure;

   - a second enclosure (81) forming a barrel, extending along the axis X' and guided in rotation about the axis X' inside the external enclosure;

   - at least one internal third enclosure (82A) and one internal fourth enclosure (82B) each extending along a longitudinal axis X1, X2 parallel to the axis X' and each adapted to accommodate an object of elongate shape, the at least two internal enclosures being fastened to each other and guided in translation in the barrel over a stroke A0;

   each internal enclosure (82A, 82B) including within it:

   • a holding member (6) adapted to pick up an object of elongate shape;

   • a screw-nut mechanism (9A, 9B) consisting of a lead screw (90A, 90B) guided in rotation about the axis X1, X2 and a nut (91A, 91B) around the screw and to which the holding member is fastened, the mechanism being adapted to guide the latter in translation in the internal enclosure over a stroke A greater than the stroke A0;

   • a bottom (801A, 801B) including an opening (802A, 802B) opposite the holding member to allow an object picked up thereby to pass through;

   the hood further including:

   - at least one motor (83A, 83B) fixed above an internal enclosure and inside the barrel, the motor(s) being adapted to rotate the screw of the screw-nut mechanism of each internal enclosure and therefore the nut over the stroke A;

   - mechanical control means (84) arranged in part above the cover of the external enclosure for manually guiding the internal enclosures in translation over the stroke A0;

   - mechanical control means (85) arranged in part above the cover of the external enclosure for manually pivoting the barrel in order to bring a holding member of one of the internal enclosures opposite the opening in the bottom of the external enclosure.
2. Confinement and handling hood (8) according to Claim 1, further including an internal fifth enclosure (82C) also extending along a longitudinal axis X3 parallel to the axis X' and adapted to accommodate an object of elongate shape, the three internal enclosures (82A, 82B, 82C) fastened to one another being distributed at 120° to one another inside the barrel (81).
3. Confinement and handling hood (8) according to Claim 1 or 2, the valve (803) for blocking the opening in the bottom of the external enclosure being a guillotine valve.
4. Confinement and handling hood (8) according to Claim 1 or 2, further including a metal bellows (86A, 86B, 86C) fixed under each opening (802A, 802B, 802C) of an internal enclosure to provide the seal between the latter and the opening (802) of the external enclosure on translation of the internal enclosures in the barrel.
5. Confinement and handling hood (8) according to any one of the preceding claims, including at least two O-rings (13) each accommodated at least partly in a respective peripheral groove (14) at the top and at the bottom of the external wall of the barrel (81) to provide the seal between the latter and the external enclosure (2).
6. Confinement and handling hood (8) according to any one of the preceding claims, a motor (83A, 83B, 83C) being fixed above each internal enclosure and inside the barrel being adapted to rotate the screw of the screw-nut mechanism of said internal enclosure and therefore the nut over the stroke A.
7. Confinement and handling hood (8) according to any one of the preceding claims, the motor(s) being electric motor(s).
8. Confinement and handling hood (8) according to any one of the preceding claims, the holding member (6) being mounted on the nut (91) of the screw-nut mechanism by means of a plate (92) guided against the internal wall of the internal enclosure by at least two lugs (93) projecting from the plate and forming centring devices.
9. Confinement and handling hood (8) according to any one of the preceding claims, the mechanical control means (84) for manually guiding the internal enclosures in translation over the stroke A0 include a screw-nut mechanism (87) consisting of a lead screw (870) on a portion of a rod (871) guided in rotation about the axis X and passing through the cover (800) and a nut (872) around the screw and to which the internal enclosures (82A, 82B, 82C) are fastened.
10. Confinement and handling hood (8) according to any one of the preceding claims, mechanical control means (85) for manually pivoting the barrel including a gear mechanism (88) consisting of a gear (880) on a portion of a rod (881) guided in rotation parallel to the axis X' and passing through the cover (800) and a toothed ring (882) meshing internally with the gear and to which the barrel (81) is fastened.
11. Confinement and handling hood (8) according to any of the preceding claims, the holding member (6) including a holding head (60) adapted to be accommodated in an interior tube (1) constituting an object of elongate shape to be picked up, the interior tube itself being adapted to be inserted in an exterior tube (2).
12. Use of the hood (8) according to Claim 11 for handling and confinement of the interior tube constituting a material sample holder tube, the exterior tube constituting a measuring instrument holder.
13. Use according to Claim 12, the sample holder tube (1) being intended to accommodate a sample of nuclear materials, such as nuclear fuels, in a measurement instrument holder tube (2) intended to accommodate at least measurement sensors and where applicable a cooling system.

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