FR2874077A1 - Rigid support for sticking flexible sheet bands, has bands with ends clamped by pinching units against support back, and centering unit supported on each side wall of passages, where support`s width is slightly lower than passages` width - Google Patents

Abstract

The support (16) has a flexible sheet band, longitudinal bands, and transversal bands. The bands have ends that are clamped by pinching units (17, 18) against the support back, where the pinching units have contact bars (171, 181). A centering unit (20) is supported on each side wall of passages. Width of the support is slightly lower than width of passages in which it is positioned. An independent claim is also included for a method of sticking flexible sheet bands.

Description

The present invention relates to the bonding of flexible webs

  used especially during the production of an insulating wall and sealed a tank integrated in a supporting structure, for example the hull of a ship.

  These walls are for example used on liquefied gas transport vessels whose tanks must be perfectly sealed and sufficiently insulating to contain liquefied gas at low temperature and to limit the evaporation of said gas.

  These walls consist of two successive sealing membranes, one primary in contact with the product contained in the tank and the other secondary disposed between the primary membrane and the carrier structure, these two membranes being alternated with two thermally protected barriers. insulating. Thus known walls consist of a primary foam insulation associated with a stainless steel primary membrane and a secondary foam insulation associated with a flexible secondary membrane comprising at least one thin continuous metal sheet such as for example an aluminum foil sandwiched between two glass fabrics. There are also walls with a primary foam insulation associated with a membrane in INVAR is a steel 36% nickel thermally stable between minus 200 C and 400 C. and a secondary foam insulation associated with a flexible secondary membrane comprising at least less a thin metal sheet.

  These insulating and waterproof walls are made from a set of prefabricated panels comprising successively, between two rigid plates, the secondary insulation, the secondary membrane and the primary insulation. The primary membrane is then made on all the prefabricated panels covering the supporting structure.

  Each prefabricated panel has the general shape of a quadrilateral predominantly of rectangle shape, the primary insulation element and the secondary insulation element respectively having, in plan, the shape of a first rectangle and a second rectangle whose sides are substantially parallel, the lengths and / or the width of the first rectangle being smaller than those of the second rectangle to provide a peripheral rim. The peripheral flanges of adjacent panels and the sidewalls of the primary insulation elements define lanes, which may extend the entire length, width or height of the vessel. These corridors are filled to ensure the continuity of the seal formed by the panels before laying the primary membrane. The continuity of the primary insulating barrier is achieved by inserting pavers into the corridors. To ensure the continuity of the secondary diaphragm seal at the junction of two panels, the peripheral edges are covered before the establishment of the pavers of a flexible web strip, comprising at least one continuous thin metal sheet.

  The assembly of these panels requires very strict operating procedures and a high accuracy of assembly. Bonding of the flexible web and sealing between two panels must be particularly accurate. The amount of glue to be used to glue the strips is imposed in order to respect a certain grammage.

  A conventional method for producing sealing at the peripheral edges consists in depositing a pre-weigh volume of epoxy or polyurethane-type glue on the peripheral rims after setting up protective adhesive tapes on the inner edges of the bottom. corridor to protect against excessive overflow of glue. A continuous flexible band, available in the form of rolls, is then unrolled on the glued edges. A protective strip is then unwound on the strip of flexible web, then the set and put in place, after masking so as to eliminate any residual bubbles, is pressurized by means of a press. During the polymerization phase of the adhesive, the strip of flexible sheet covered with the protective strip is maintained under pressure at about 0.1 or 0.2 bar depending on the type of resin. This technique has the disadvantage of lacking precision, the deposited adhesive film to be as continuous and as uniform as possible and to request a significant implementation time. Moreover, once the adhesive having overflowed on the protective adhesive, is taken, it generates unwanted residues that must be removed by suction.

  A device and a method for producing the sealing at the peripheral edges are also known from the patent FR 2 822 815. This device comprises among other means allowing it to unwind a strip in a corridor and the process therefore consists of another to unwind continuously a strip of flexible web, available as pre-glued rolls or not. This device has the disadvantage of being complex because of the different functions it fulfills.

  In addition, in both of the aforementioned methods, the use of webs in the form of rolls makes it difficult for the webs to be properly positioned in the aisles and the resulting seal can be defective.

  The invention aims to remedy the aforementioned drawbacks of the prior art. That is to say, in particular to propose a device and a method for bonding flexible webs, easily providing the necessary precision to obtain a required seal, saving time, generating the least possible defects , dusts and dirt, and requiring only simple means of implementation.

  To this end, the subject of the invention is a rigid support for bonding strips of flexible plies in corridors defined by the adjacent edges of prefabricated quadrilateral panels, constituted by at least two insulating layers, attached to the wall of a tank. integrated in a support structure, characterized in that it comprises means for positioning, clamping and tensioning the pre-cut strips that it receives and centering means in the corridors. Such a device makes it easier to perform the operations that a web undergoes and facilitates the handling of a pre-cut flexible strip regardless of its orientation in space.

  According to a particular feature of the invention, the width of the rigid support is slightly less than the width of the corridor in which it is positioned and it has on the lateral sides centering means bearing on each side wall of the corridor. In this way, the rigid support can be easily set up and removed from the corridor by an operator while providing support for the width of the precut strips.

  According to a particular characteristic of the invention, the clamping of the band that the rigid support receives is ensured by clamping means blocking the ends of the band against the back of said rigid support. It is thus possible to quickly clamp the precut strip to a predefined length.

  According to a particular characteristic of the invention, the tensioning of the band is ensured by means of translation of at least one of the clamping means of the band. This translation along the long length of the rigid support is obtained for example by the action of a grasshopper associated with a spring or Belleville washers which translate the clamping means towards the center of the rigid support. A grasshopper is an articulated locking mechanism that opens or closes quickly also known in English as the toggle clamp.

  Advantageously, the length of the rigid support may be variable depending on the length of the band that it receives and substantially equal to said length. It is therefore possible to manipulate strips of different lengths with the same support.

  The invention also relates to a method for bonding flexible webs, in particular in corridors defined by the adjacent edges of prefabricated quadrilateral panels, consisting of at least two insulating layers, attached to the wall of the tank integrated in a support structure, the strips ensuring the sealing of said tank at the junctions of the prefabricated panels, characterized in that it comprises the steps of: - tensioning on rigid supports pre-cut strips of defined length, positioned on protection films of defined length, pre-gluing of pre-cut strips, positioning of strips in the channels by rigid supports, separation of strips and rigid supports, removal of rigid supports, pressurization of strips, removal of film from protection.

  The positioning of the strips is thus obtained quickly with sufficient precision. In addition, the tension of the strip makes it possible, at the time of its application against the bottom of the passage, to generate fewer bubbles, by trapping air between the glue and the bottom of the passage, in the glue film improving its continuity. Advantageously, certain steps can be performed simultaneously by different operators. The pre-gluing pre-gluing step may in particular be carried out by an operator while other operators position the strips in the corridors. This reduces the time of completion of the sealing of a wall.

  According to a particular characteristic of the invention, the method is carried out using rigid supports as described above.

  According to one particular characteristic of the invention, the pre-gluing of the flanged and tensioned strips on the rigid supports is done by means of an automatic gluing machine which deposits on the strips a predetermined quantity of glue in the form of at least a glue film. The grammage constraints are then easily respected and with great repeatability. In addition the risks of overflow of glue are better controlled which eliminates the step of placing protective adhesive tapes on the inner side edges of the corridor.

  According to another particular feature of the invention, the method consists of different steps: - sticking a first set of so-called longitudinal said precut strips glued in the so-called longitudinal corridors by arranging the strips almost edge to edge at the junctions of the prefabricated panels, sticking a second set of so-called transverse precut strips glued in the so-called transverse lanes, above the longitudinal strips already glued by leaving a predefined clear space between two consecutive transverse precut bands, glue a third set of so-called transverse strips glued in the so-called transverse lanes on the previous free spaces and the edges of the already glued transverse strips.

  In this way the transverse strips finish the sealing of a wall at the junctions of the longitudinal strips and the finalization by the third set may be according to the method of the invention or according to the previously known manual methods. This finalization makes it possible to obtain a seal at the level of the transverse strip connection junctions itself.

  According to a particular feature of the invention, the precut strips have a length substantially equal to a length multiple of the length of one side of the panels.

  Reading the description below will help in understanding the invention. This description, given solely by way of example, is made with reference to the accompanying drawings, in which: FIG. 1 shows a sectional view of an insulation panel, FIG. 2 shows, in sectional view, the junction between FIG. 3 shows a general view of a wall before bonding the strips of flexible sheets. FIGS. 4, 5 and 6 show, viewed from the front, a preferred arrangement of the longitudinal strips and the transverse strips according to different stages of FIGS. 7a, 7b and 7c show a strip, its protective film and the adhesive films deposited on this strip. FIG. 8 is a simplified sectional view of a rigid support. FIG. 9 is a partial perspective view of a rigid support according to the invention in the bonding position.

  The prefabricated panel 1 according to FIG. 1 consists of a primary insulation 8 and a secondary insulation 9. Between the primary insulation 8 and the secondary insulation 9 is inserted a flexible or rigid secondary membrane 10 and comprising at least one continuous thin metal sheet. The primary insulation is covered with a plywood 7 which provides the superior rigidity of the panel 1. The secondary insulation 9 is bonded to a plywood 11 which provides the lower rigidity of the panel 1. The primary insulation 8 is shorter and less wide than the secondary insulation 9 to create a space on the entire periphery of the panel 1 and creates a corridor 12 when two panels are arranged side by side as shown in Figure 2.

  FIG. 2 shows two prefabricated panels 1 between which is placed an insulating joint 2 over the entire height of the secondary insulation 9. The primary insulation 8 being smaller than the secondary insulation 9, a corridor 12 separates the two primary insulators of the two panels 1. A strip of flexible sheet 3 comprising at least one thin continuous metal sheet is bonded astride the two secondary insulators 9 and the insulating seal 2.

  Figure 3 shows a set of panels 1 constituting the insulation of a wall 4. Between the panels 1 are defined longitudinal corridors 12a and transverse 12b. The insulating joints 2 placed between the secondary insulation layers 9 of adjacent panels 1 are also visible in this figure.

  Figure 4 shows the state of the wall 4 after gluing the set of longitudinal strips 3a in the longitudinal lanes 12a. This state is obtained by a preferred embodiment of the method in which the whole of the longitudinal strips 3a of length substantially equal to one times the length of a panel 1 without overlap between these same strips 3a, La is firstly glued. FIG. 5 shows the state of the same wall 4 once the gluing of the longitudinal strips 3a and of the transverse strips 3b has been completed. The strips 3b have a length substantially equal to twice the width of a panel 1, are centered on the width of a panel 1, and a space 15 between two transverse strips 3b is left free in a first step and has a length equivalent to the width of a prefabricated panel.

  FIG. 6 shows the state of the same wall 4 once the gluing of the longitudinal strips 3a and of the transverse strips 3b, 3c has been completed. The transverse strips 3c partially cover the ends of the transverse strips 3b and have a length substantially greater than once the width of a panel 1. The strips 3b and 3c cover the longitudinal strips 3a at the crossings of the longitudinal and transverse channels 12a and 12b. .

  FIGS. 7a, 7b and 7c show an assembly 6 consisting of the flexible ply strip 3, positioned and centered on the protective film 5, at different stages of the gluing step in a preferred case where gluing is equivalent to successive deposition of two parallel adhesive films 13 and 14. Advantageously, the adhesive films will be deposited by an automatic sizing device (not shown) which may be, for example, a nozzle head with two transverse positions and disposed above a two-way conveyor, the nozzle head deposits a first glue film during a first go and a second glue film during a second go.

  To seal a wall 4 according to the method using rigid supports 16, it is advantageous to glue in a first time all the longitudinal strips 3a.

  In this preferred case all the longitudinal strips are glued in the longitudinal lanes 12a, without overlap between these strips 3a, then are glued all the transverse strips 3b in the transverse lanes 12b and finally are glued manually or pre-glued the together transverse bands 3c in the transverse corridors 12b at the spaces 15 left free (see Figure 5). The transverse strips 3b and 3c, which terminate the seal, partially overlap for a sufficient length to seal and cover, at the intersection between the longitudinal and transverse channels 12a and 12b, the longitudinal strips 3a previously glued on almost the edges. on board. The surface on which the transverse strips 3b and 3c are bonded thus locally has irregularities due to the presence of the longitudinal strips 3a. In the presence of these irregularities, a person skilled in the art may find it advantageous to add glue beads locally before gluing the transverse strips 3b and 3c, for example on the edges of the ends of the longitudinal strips 3a or to fully glue the transverse strips 3b. 3c manually without using rigid supports 16 and according to currently known methods to achieve sealing of the assembly.

  FIGS. 8 and 9 show a preferred configuration of a rigid support 16 comprising pinch means 17 and 18 consisting for example of contact bars 171, 181 held in pressure on the back 161 of the rigid support 16 via locking means 172 , 182 of type grasshopper. The clamping means 18 is associated with a tensioning means 19 which may, for example, consist of a plate 191 on which the clamping means 18 is fixed, said plate 191 being able to slide towards the center of the support 16 by Belleville washer 192 which is compressed and blocked at the desired tension by a jamming means 193 of the grasshopper type. An assembly 6 comprising a strip 3 and a protective film 5 is shown held in position and stretched on the rigid support 16. The rigid support 16 also comprises centering means 20 (FIG. 9) of the support in a corridor 12, for example stop type disposed on either side of the lateral sides of the support 16, as well as positioning means such as a visual cue for example (not shown) of the assembly 6 on the rigid support 16.

  By way of example, we will describe the operations undergone by a longitudinal strip 3a glued according to the method in a longitudinal lane 12a, the transverse strips 3b and 3c glued in the transverse lanes 12b being able to undergo the same operations.

  Each strip 3a bonded according to the invention is cut to the appropriate length then positioned and centered on the protective film 5 thus forming the assembly 6. An operator then installs the assembly 6 on the rigid support 16 whose length is adapted to the length of the assembly 6 that he will receive. For this purpose advantageously has a range of rigid supports 16 of different lengths or rigid supports 16 whose length is adaptable. This operation consists of positioning the rigid support 16 on the assembly 6 then to actuate the holding means in position 17 and 18 of the assembly 6 on the rigid support 16 and finally to actuate the tensioning means 19 of the assembly 6 on the rigid support 16. The band 3a thus mounted on its rigid support 16 is then preferably glued by means of an automatic gluing machine (not shown) which, advantageously, deposits on the length of the strip 3a two films parallel glue 13 and 14. The rigid support 16 is placed in position in the corridor 12a and the assembly 6 is separated from the rigid support 16 either by releasing the assembly 6 of the clamping means 17, 18, or by cutting the ends 6. The rigid support 16 is then removed and can be used for another band 3a. The assembly 6 thus being properly positioned in the passageway 12a can then be pressurized by any means during the setting time of the glue. The protective film 5 collects the glue, possibly in excess, and makes it possible to avoid inadvertent bonding of the pressurizing means to the glued strip 3a. The protective film 5 is then removed. The result obtained then has a finite appearance.

  All of these operations are repeated for each strip 3. To reduce the duration of the realization of the tightness of the wall, cutting operations, mounting strips 3 and protective films 5 on the rigid supports 16 and sizing can be carried out by one or more operators while one or more other operators position the rigid supports 16 in the corridors 12 and disconnect them from the strips 3. The rigid supports 16 containing the glued strips 3 can then be momentarily as needed stored, for example on a carriage and thus be brought into stock on the work areas. io

Claims (9)

  Rigid support (16) for bonding strips of flexible plies (3, 3a, 3b, 3c) in corridors (12, 12a, 12b) defined by adjacent flanges of prefabricated quadrilateral panels (1), consisting of at least two insulating layers (8, 9) fixed to the wall (4) of a vessel integrated in a supporting structure, characterized in that it comprises positioning, clamping (17, 18) and positioning means in tension (19) pre-cut strips (3, 3a, 3b, 3c) it receives and positioning means (20) in the corridors (12).   2. Rigid support (16) for bonding strips of flexible plies (3, 3a, 3b, 3c) according to the preceding claim characterized in that its width is slightly less than the width of the corridor (12, 12a, 12b) in which he positions himself.   3. Rigid support (16) for bonding strips of flexible plies (3, 3a, 3b, 3c) according to the preceding claims, characterized in that the clamping of the strip (3, 3a, 3b, 3c) that it receives is provided by pinching means of the ends of the strip (3, 3a, 3b, 3c) against the back of said rigid support (16).   4. Rigid support (16) for bonding strips of flexible plies (3, 3a, 3b, 3c) according to the preceding claims, characterized in that the tensioning of the strip (3, 3a, 3b, 3c) is ensured by translation means of at least one of the clamping means (17, 18) of the strip (3, 3a, 3b, 3c).   5. A method for bonding flexible webs (3, 3a, 3b, 3c) in corridors defined by the adjacent edges of prefabricated quadrilateral panels (1), consisting of at least two insulating layers (8, 9), attached to the wall (4) of a tank integrated in a supporting structure, the strips (3, 3a, 3b, 3c) sealing said tank at the junctions of the prefabricated panels (1), characterized in that it comprises the steps of: - tensioning on rigid supports (16) strips of pre-cut flexible plies (3, 3a, 3b, 3c) of defined length, positioned and centered on protective films (5) of length defined, - pre-gluing of pre-cut strips (3, 3a, 3b, 3c), positioning of strips (3, 3a, 3b, 3c) in the channels by rigid supports (16) 2874077 >> - separation of strips (3 , 3a, 3b, 3c) and rigid supports (16) - removal of the rigid supports (16) - pressurization of the strips (3, 3a, 3b, 3c) - removal of protective films (5) 6. A method of bonding flexible webs (3, 3a, 3b, 3c) according to claim 5, characterized in that it is achieved by means of rigid supports (16) according to claims 1 to 4.   7. A method of bonding flexible webs (3, 3a, 3b, 3c) according to claims 5 and 6, characterized in that the pre-gluing of the strips (3, 3a, 3b, 3c) clamped and tensioned on the rigid supports (16) is effected by means of an automatic gluing machine which deposits on the strips (3, 3a, 3b, 3c) a predetermined quantity of adhesive in the form of at least one glue film (13, 14 ).   8. A method of bonding flexible webs (3, 3a, 3b, 3c) according to claims 5 to 7 characterized in that it consists of different steps: - glue a first set of strips (3a) pre-cut longitudinal said glued in the so-called longitudinal corridors (12a) by arranging the bands (3a) almost edge-to-edge at the junctions of the prefabricated panels (1), - gluing a second set of so-called transverse precut strips (3b) glued in the corridors (12b) said transverse, above the longitudinal strips (3a) already glued by leaving a free space (15) predefined between two transverse strips (3b) pre-cut already glued consecutive, - glue a third set of strips (3c) called transverse glued in the corridors said transverse (12b) on the previous free spaces (15) and the edges of the transverse strips (3b) already glued.   9. A method of bonding flexible webs (3, 3a, 3b, 3c) according to claims 5 to 8 characterized in that the strips (3, 3a, 3b, 3c) have a length substantially equal to a multiple length of the length of one side of the panels (1).