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EP-4735769-A1 - BONDED ASSEMBLY AND METHOD FOR THIS ASSEMBLY

EP4735769A1EP 4735769 A1EP4735769 A1EP 4735769A1EP-4735769-A1

Abstract

The invention relates to a bonded assembly comprising a first element (4; 24) having a first bonding surface (4a; 24a) and a bearing region (4b; 24b) surrounding the first bonding surface, a second element (6; 26) having a second bonding surface (6a; 26a), a non-crosslinked mastic bead (12) surrounding the first and second bonding surfaces (4a, 6a; 24a, 26a) and squashed between the bearing region (4b; 24b) and the second element (6; 26), and a cured adhesive (8) in contact with the first and second bonding surfaces and isolated from the outside by a seal comprising the non-crosslinked mastic bead (12).

Inventors

  • COURT, JEAN-PHILIPPE
  • DOUXCHAMPS, Gaspard

Assignees

  • Cold Pad

Dates

Publication Date
20260506
Application Date
20240628

Claims (18)

  1. [Claim 1] Glued assembly, comprising: - a first element (4; 24) having a first bonding surface (4a; 24a) and a support zone (4b; 24b) surrounding the first bonding surface; - a second element (6; 26) having a second bonding surface (6a; 26a); - a bead of non-crosslinked mastic (12) surrounding the first and second bonding surfaces (4a, 6a; 24a, 26a) and crushed between the support zone (4b; 24b) and the second element (6; 26); and - a cured adhesive (8) in contact with the first and second bonding surfaces and isolated from the outside by a seal comprising the non-crosslinked mastic bead (12).
  2. [Claim 2] A bonded assembly according to claim 1, wherein the first element (4) comprises a groove (4c) formed between the first bonding surface (4a) and the support zone (4b).
  3. [Claim 3] Bonded assembly according to any one of claims 1 and 2, in which the support zone (4b) comprises, along its circumference, a protuberance (16) oriented towards the second element (6) and coated by the non-crosslinked mastic.
  4. [Claim 4] Bonded assembly according to any one of claims 1 to 3, in which the first element (4) comprises a first portion (32) comprising the first bonding surface (4a), and a second portion (34) comprising the support zone (4b).
  5. [Claim 5] A bonded assembly according to claim 4, wherein the second portion (34) comprises a lip (35) which extends inwardly from the bearing zone (4b) and is arranged to cover an outer edge (33) of the first portion (32).
  6. [Claim 6] A bonded assembly according to any one of claims 4 and 5, wherein a desiccant is housed between the first and second portions (32, 34).
  7. [Claim 7] A bonded assembly according to any one of claims 1 to 6, wherein the joint further comprises an elastomer portion (10a) surrounding the bead of non-crosslinked mastic (12), such that the crushing of the bead of non-crosslinked mastic is effected by contact between the support zone (4b) and the mastic, on the one hand, and by contact between the second element (6) and the mastic, on the other hand.
  8. [Claim 8] Bonded assembly according to any one of claims 1 to 7, in which the first element (4) comprises at least one hole (20) opening onto the first bonding surface (4a).
  9. [Claim 9] A bonded assembly according to claim 8, wherein the hole (20) opens onto a surface (4e) of the first element (4) opposite the first bonding surface (4a), the bonded assembly further comprising a shutter (22) arranged in the hole to admit a circulation of fluid only from the first bonding surface to the opposite surface.
  10. [Claim 10] A bonded assembly according to any one of claims 1 to 9, wherein the first bonding surface (4a) comprises reliefs.
  11. [Claim 11] A bonded assembly according to any one of claims 1 to 10, wherein the non-crosslinked sealant is butyl-based.
  12. [Claim 12] A method of assembling a first element with a second element, wherein the first element (4) comprises a first bonding surface (4a) and a support zone (4b) surrounding the first bonding surface, wherein the second element (6) comprises a second bonding surface (6a), wherein a bead of non-crosslinked mastic (12) is arranged on the support zone (4b) around the first bonding surface (4a), the method comprising: - placing an adhesive between the first and second bonding surfaces (4a, 6a); - reducing the pressure within a volume (44) adjacent to the second element (6) and containing the first element (4); - moving the first element (4) towards the second element (6) to crush the non-crosslinked mastic bead (12); and - allow the adhesive (8) to harden between the first and second bonding surfaces.
  13. [Claim 13] The assembly method of claim 12, wherein the volume (44) adjacent the second member includes a first volume (44a) and a second volume (44b) on either side of a piston (46), wherein the first member (4) is mounted on the piston and is contained in the second volume (44b), and wherein moving the first member (4) toward the second member (6) includes applying a lower pressure in the second volume (44b) than in the first volume (44a) to slide the piston (46) toward the second member (6).
  14. [Claim 14] An assembly method according to any one of claims 12 and 13, in which an assembly tool (36) comprising an enclosure (38) delimiting the volume (44) adjacent to the second element is dismantled after moving the first element (4; 24) towards the second element (6; 26).
  15. [Claim 15] An assembly method according to claim 14, wherein the disassembly of the assembly tool (36) is carried out before hardening of the adhesive (8).
  16. [Claim 16] Structural element to be bonded, comprising: - a bonding surface (4a) extending perpendicular to an assembly direction (X); - a support zone (4b) surrounding the bonding surface; and - a bead of non-crosslinked mastic (12) arranged along the support zone (4b) and projecting, along the assembly direction (X), beyond the bonding surface (4a).
  17. [Claim 17] Structural element to be bonded according to claim 16, in which the support zone (4b) is set back from the bonding surface (4a) in the assembly direction (X).
  18. [Claim 18] A structural element to be bonded according to any one of claims 16 and 17, further comprising a dose of adhesive (7) placed on the bonding surface (4a). [Claim 19] A structural element to be bonded according to claim 18, in which the dose of adhesive (7) is isolated from the outside by a peelable film (9).

Description

Description Title: GLUED ASSEMBLY AND PROCESS FOR THIS ASSEMBLY Technical field [0001] The present invention relates to techniques for producing bonded assemblies. These techniques can be used in various fields of construction or industry, such as for example for fixing elements on a wind turbine mast or on a floating building such as a ship or a platform. Previous technique [0002] Bonded assemblies use adhesives that require a hardening or polymerization time. This is particularly the case for two-component adhesives. [0003] Bonded assembly techniques, described in particular in WO 2010/146321 A1, can be used to make connections between structural elements or to reinforce a structural element. [0004] In some proposals, such as those described in US 4,842,912 A and WO 2017/089668 A1, an installation tool is used to hold a mechanical connector in place during the adhesive curing phase, which lasts from about 5 minutes to more than an hour. The installation tool is immobilized during the curing time and therefore cannot be used for the installation of other connectors. If several connectors must be installed with a single tool, the immobilization of the latter reduces productivity. [0005] In WO 2010/146321 A1 and WO 2017/089668 A1, the bonded assemblies use a crosslinked elastomer seal that is compressed to delimit a sealed volume containing the adhesive. After the latter has hardened, the elastomer seal remains compressed to maintain the seal and protect the adhesive from the external environment. The crosslinked elastomer seals are capable of absorbing the surface irregularities of the two assembled elements and ensuring the seal. In the case of a small connector, for example with a diameter of between 25 mm and 500 mm, the O-rings have a thickness of the order of 1 mm to 10 mm. Surface irregularities of several millimeters can then be too large and make the adhesive accessible to the external environment, thus affecting the durability of the bonded assembly. Additionally, cross-linked elastomer gaskets have elastic behavior, meaning they exert a spring force when compressed. If the installation tool is removed too early, this spring force can cause the mating surfaces to separate before the adhesive has fully cured, compromising the integrity of the adhesive layer between the surfaces. [0006] There is a need to overcome this type of limitation and to have a reliable and efficient technique for assembling two elements. Summary [0007] A bonded assembly is proposed, comprising: - a first element having a first bonding surface and a support zone surrounding the first bonding surface; - a second element having a second bonding surface; - a bead of non-crosslinked mastic surrounding the first and second bonding surfaces and crushed between the support zone and the second element; and - a cured adhesive in contact with the first and second bonding surfaces and isolated from the outside by a seal comprising the non-crosslinked mastic bead. [0008] The joint using a non-crosslinked sealant crushed between the first and second elements conforms to the facing surfaces of the two elements while admitting that one or the other of these surfaces has irregularities. [0009] The non-crosslinked mastic has negligible elasticity and, on the other hand, a sticky or tacky behavior. The assembly is made easier since the material of the joint tends to hold the two elements against each other rather than to separate them. If the installation of the second element uses a vacuum, a suction effect is obtained at the interface between the two elements and this suction effect makes it possible to disassemble the installation tool without waiting for the adhesive to harden. [0010] The first element may comprise a groove formed between the first bonding surface and the support zone. [0011] The support zone may comprise, along its circumference, a protuberance oriented towards the second element and coated with the non-crosslinked mastic. [0012] The first member may include a first portion having the first bonding surface, and a second portion having the bearing area. The second portion may include a lip that extends inwardly from the bearing area and is arranged to cover an outer edge of the first portion. A desiccant may be housed between the first and second portions. [0013] In a particular embodiment, the seal further comprises an elastomer portion surrounding the bead of non-crosslinked mastic, such that the crushing of the bead of non-crosslinked mastic is carried out by contact between the support zone and the mastic, on the one hand, and by contact between the second element and the mastic, on the other hand. [0014] The first element may comprise at least one hole opening onto the first bonding surface. The hole may open onto a surface of the first element opposite the first bonding surface, the bonded assembly further comprising a shutter arranged in the hole to admit a circulation of fluid only from the first bonding surface to