Fastening assembly of a fire door to a bulkhead

Abstract

A fastening assembly of a fire door to a bulkhead includes a shaped frame, to which is hinged the door, which includes a first bracket facing at least in part a first side surface of the bulkhead, and a primary flange, mechanically connected to the first bracket. The fastening assembly has a subframe, which in turn includes a second bracket, parallel to the first bracket and facing a second side surface of the bulkhead, and at least one secondary flange, mechanically connected to the second bracket. At least one joint mutually connects the frame and the subframe, to retain the bulkhead between the first and the second bracket mutually facing, without engaging simultaneously the bulkhead the portion of the first bracket facing the first side surface and the portion of the second bracket facing the second side surface.

Claims

1. A fastening assembly of a fire door to a bulkhead, said bulkhead comprising a first side surface and a second side surface opposite to the first side surface; said assembly comprising: a shaped frame, which the door is hinged to, the shaped frame includes: a first bracket, at least partly facing the first side surface of said bulkhead; and at least one primary flange, mechanically connected to said first bracket; a subframe comprising: a second bracket, parallel to the first bracket and facing the second side surface of said bulkhead; and at least one secondary flange mechanically connected to said second bracket; at least one joint, able to tighten the frame to the subframe to retain the bulkhead between said mutually facing first and second brackets; wherein: the at least one joint connects the at least one primary flange with the at least one secondary flange, avoiding engaging at the same time the portion of the first bracket facing the first side surface and the portion of the second bracket facing the second side surface, and avoiding directly engaging the bulkhead, the at least one joint being oriented along an axis parallel to said first and second brackets.

2. An assembly according to claim 1, wherein said first and second brackets are separated by a preset first transverse distance.

3. An assembly according to claim 1, wherein said primary and secondary flanges have a length, measured with respect to a direction perpendicular to the bulkhead, such that the door lies substantially on a same plane defined by said bulkhead.

4. An assembly according to claim 1, wherein the frame comprises a plurality of primary flanges substantially aligned along a direction perpendicular to the bulkhead, so that, by varying a number and/or extension of said flanges along said perpendicular direction, a second transverse distance, between the bulk-head and a closure plan of the door changes.

5. An assembly according to claim 1, wherein said assembly connects the door to a structure fixed perpendicular to the bulk-head.

6. An assembly according to claim 1, wherein between the first bracket and the bulkhead, and/or between the second bracket and the bulkhead, a sealing adhesive and a heat-expanding gasket are interposed.

7. An assembly according to claim 1, wherein the frame is a composite frame and is formed by a plurality of juxtaposed frame portions.

8. An assembly according to claim 1, wherein the fire door is made of a malleable material and has a yield stress greater than or equal to 230 MPa.

9. An assembly according to claim 8, wherein the material is S235, S275 or S355 structural steel.

10. A vessel, comprising at least one bulkhead and at least one fastener assembly of a fire door to the bulkhead, according to claim 1.

11. A method for fastening a fire door to a bulkhead, comprising the steps of: a) providing a frame comprising a first bracket and at least one primary flange; b) providing a subframe comprising a second bracket and at least one secondary flange; c) arranging the frame so that the first bracket at least partly faces a first side surface of said bulkhead; d) arranging the subframe so that the second bracket at least partly faces a second side surface of said bulkhead opposite to the first side surface; e) providing at least one joint; f) connecting, via the at least one joint, the at least one primary flange to the at least one secondary flange so that the joint avoids simultaneously engaging the portion of the first bracket facing the first side surface and the portion of the second bracket facing the second side surface of the bulkhead, and avoids directly engaging the bulkhead and so that the at least one joint is oriented along an axis parallel to said first and second brackets; g) hinging the fire door to the frame.

12. A method according to claim 11, wherein step (f) is performed so that the portion of the first bracket, facing the first side surface, and the portion of the second bracket, facing the second side surface of the bulkhead, are separated by a preset first transverse distance.

13. A method according to claim 11, wherein step (f) is performed so that the door, when in a closed position, substantially lies on a same plane defined by the bulkhead.

14. A method according to claim 11, wherein step (f) is followed by the step of aligning, in a direction perpendicular to the bulkhead, and mutually joining a plurality of primary flanges, so as to vary a second transverse distance between the bulkhead and a plane on which the door lies when in a closed position.

15. A method according to claim 11, further comprising the step of providing a structure that includes at least a first additional bracket and at least a second additional bracket.

16. A method according to claim 15, comprising the step of securing the first additional bracket to the bulkhead and securing the second additional bracket to the first additional bracket, so that said second additional bracket is at least partly received between at least part of the first bracket and at least part of the second bracket and are mutually facing.

17. A method according to claim 11, further comprising the step of inserting between the portion of the first bracket facing the first side surface and the bulkhead, and/or between the portion of the second bracket facing the second side surface and the bulkhead, a sealing adhesive and a heat-expanding gasket.

18. A method according to claim 11, further comprising the step of composing the frame by juxtaposition of a plurality of frame portions.

19. A method according to claim 11, further comprising the step of providing the fire door in a malleable material which has a yield stress greater than or equal to 230 MPa.

20. An assembly according to claim 19, wherein the material is S235, S275 or S355 structural steel.

21. A method for securing a fire door to a bulkhead of a vessel, comprising the steps of claim 11.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The operational and structural features of some preferred embodiments of a fastening assembly according to the invention will now be described. Reference is made to the accompanying drawings, in which:

(2) FIGS. 1 and 2 are diagrammatic perspective views in partial longitudinal section of a vessel and of a detail of the vessel in FIG. 1, respectively;

(3) FIG. 3 is a diagrammatic view of a detail of FIG. 2, which shows a plurality of bulkheads on which a plurality of doors is mounted, according to the prior art;

(4) FIGS. 4 and 5 are stress diagrams of a vertical section of the hull of a vessel and of the vicinity of the compartment of a door, respectively, when the vessel is subjected to the wave load;

(5) FIGS. 6 and 7 are diagrammatic cross-sectional views of two fastening assemblies of a door to a bulkhead, according to the prior art;

(6) FIG. 8 is a diagrammatic cross-sectional view of a fastening assembly according to an embodiment of the present invention;

(7) FIGS. 9 and 10 are diagrammatic, axonometric views, a front and a back view respectively, of a door mounted on a bulkhead, according to the embodiment of the invention in FIG. 9;

(8) FIG. 11 is a diagrammatic sectional view of a detail of FIG. 10;

(9) FIGS. 12 and 13 are diagrammatic cross-sectional views of two further embodiments of a fastening assembly according to the present invention;

(10) FIG. 14 is a diagrammatic cross-sectional view of a fastening assembly according to an embodiment of the present invention;

(11) FIG. 15 is a diagrammatic perspective view of a feature of a fastening assembly subjected to deformation due to intense heat;

(12) FIG. 16 is a comparative graph of the relative door-frame displacement, as a function of time, of a fastening assembly according to the prior art and of an assembly according to the invention, when the assembly is hit by intense heat.

DETAILED DESCRIPTION

(13) Before explaining in detail a plurality of embodiments of the invention, it should be clear that the invention is not limited in the application thereof to the constructional details and to the configuration of the components disclosed in the following description or shown in the drawings.

(14) Referring first to FIGS. 1 and 2, a vessel 5 has a plurality of bulkheads 10, on which openings adapted to receive fire doors 11 may be obtained, connected to the bulkheads by means of frames 12 (seen in FIG. 3).

(15) Referring then to FIGS. 6 and 7, concerning two fastening solutions of the fire door 11 to the bulkhead 10 according to the prior art, frame 12 is an extruded metal element which has a bracket 12a parallel to said bulkhead 10. Frame 12, to which the door or leaf or wing 11 is hinged, is rigidly constrained to the bulkhead by means of a certain number of joints 16. Such joints may be of the bolt type, or may be in the form of a spot or continuous weld. Wing 11 is made of a malleable material which has a sufficient fire resistance; the wing or fire door 11 is preferably made of a material which has a yield stress greater than or equal to 230 MPa; preferably, S235, S275 or S355 structural steel may be used.

(16) In FIG. 6, the frame is directly constrained to bulkhead 10 by means of bolted joints 16 passing through said bulkhead 10; in the example in FIG. 7, instead, the constraint made by the bolted joints 16, passing through bulkhead 10, is reinforced thus forcing said bulkhead 10 between the first bracket 12a of frame 12, and a second bracket 14a of a subframe 14. The second bracket 14a is parallel to both the first bracket 12a and the bulkhead 10, and is connected to the first bracket 12a by means of additional bolted joints arranged in a direction perpendicular to bulkhead 10. Therefore, the first bracket 12a will face a first side surface 10a of bulkhead 10, while the second bracket 14a will face a second side surface 10b, opposite to the first side surface 10a, of bulkhead 10.

(17) Joint 16, as previously mentioned, exerts a tightening action between the two brackets 12a, 14a, which rigidly retains bulkhead 10 between said brackets. Joint 16 may be made by coupling a countersunk screw 16a to a nut 16b, possibly with the interposition of a washer 16c between the nut and the subframe.

(18) FIG. 8 shows an embodiment of a fastening assembly 9 of door 11 to bulkhead 10, according to the present invention. Also in this case, frame 12 and subframe 14 (which form the fastening assembly 9) have two brackets 12a, 14a at least partly facing and parallel to bulkhead 10, said brackets being separated by a first transverse distance A set to limit, without clasping, the bulkhead 10. Said distance A may be substantially equal to or greater than the thickness of bulkhead 10; optionally, there may be a clearance between the bulkhead and the frame/subframe, so as to facilitate the mutual movement between the parts and further decrease the friction.

(19) However, between the portions of such brackets 12a, 14a which face the first side surface 10a and second side surface 10b, respectively, there are no junctions nor connecting elements, adapted to transmit a tightening force between the two brackets. Moreover, the joint does not engage nor perforate the bulkhead, thus avoiding unwanted tensions from being generated and effectively decoupling the bulkhead from the frame, as already said. In the example shown herein, the joints 16 are arranged so as to have longitudinal axis x parallel to bulkhead 10; a connection of the above-described type may be made by mutually constraining at least one primary flange 12b and at least one secondary flange 14b, forming part of frame 12 and subframe 14, respectively, by means of the aforesaid joints 16, said flanges being mechanically connected to said first and second brackets 12a, 14a. Joint 16 may be provided with an anti-unscrewing system in order to avoid the risk of disassembly during the ship operation.

(20) The number and orientation of said primary and secondary flanges may be variable, as well as the orientation of the joints 16 which connect such flanges (see, for example, FIG. 14), as long as no coupling between the aforesaid portions of the brackets 12a, 14a facing the bulkhead 10 is achieved, such as to generate an exchange of forces between said portions of the brackets.

(21) In any case, said flanges 12b, 14b must be mutually fastened so as to ensure, between the aforesaid portions of the brackets 12a, 14a facing the bulkhead 10, the first transverse distance A as predetermined, so that the fastening constraint of the door to the bulkhead is not of the rigid type, and since the tightening action is much lower with respect to the cases contemplated in the prior art, the stresses transmitted from the bulkhead to the frame will also be less harmful. In the example shown in FIG. 14, in order to ensure the correct extension of said distance A, the dimensional tolerances when manufacturing the various flanges 12b, 14b of the frame and the subframe should be particularly taken into account.

(22) Frame 12, according to an embodiment (not shown), may consists of multiple juxtaposed frame segments or portions, rather than being monolithic as in the example shown herein.

(23) Moreover, it may be made of extruded aluminum, and made heat-resistant by means of a frame top (not shown), made of steel for example.

(24) Subframe 14 (as seen in FIGS. 10 and 11) preferably comprises a plurality of plates spaced apart and bent at right angles, rather than being a single continuous extruded piece completely overlapping frame 12.

(25) The joints 16, in place of the bolted joints depicted here, may be of the welded type, or may be interlocking systems, according to embodiments not shown.

(26) FIGS. 12 and 13 show two further embodiments of a fastening assembly according to the present invention, adapted to allow door 11 to be installed on a plane transversely spaced apart from bulkhead 10.

(27) Throughout the present description and in the claims, the terms and expressions indicating positions and orientations, such as longitudinal, transverse, vertical or horizontal, shall be referred to bulkhead 10.

(28) In the example shown in FIG. 12, the fastening assembly including frame 12 and subframe 14 being facing, is similar to the previously described cases; in the example shown herein, the assembly 9 of frame 12 and subframe 14 is not directly connected to the bulkhead, but to a structure 20 comprising, according to an embodiment of the invention, a first and a second additional bracket 21, 22, conveniently welded together and rigidly connected to bulkhead 10. Such additional brackets 21, 22 may be variable in number, size and orientation, provided that the second additional bracket 22 is shaped and oriented so as to be received between the first 12a and second 14a of the brackets facing frame 12 and subframe 14; it is meant that, with regard to the features of said second additional bracket 22 and of the connection thereof to the fastening assembly 9, the same applies as previously said in connection with the modes of connecting assembly 9 to bulkhead 10.

(29) The use of such a structure 20, as already mentioned, allows the door to be placed on a staggered plane with respect to bulkhead 10, while making the installation of door 11 on board of the vessel easier, since the structure and the door may be preassembled or retrofitted on the bulkhead. Therefore, the difference with respect to the previously discussed cases consists in that, in place of bulkhead 10, the first and the second brackets 12a, 14a of the fastening assembly will be connected to the structure 20, in place of the bulkhead 10 of the vessel.

(30) FIG. 13 shows an alternative embodiment, also adapted to space the bulkhead 10 from the leaf 11 of the door transversely. In this case, frame 12 comprises a certain number of the primary flanges 12b, mutually aligned and joined along a direction perpendicular to bulkhead 10, so as to increase or vary a second transverse distance B between the bulkhead and the leaf, when the latter is in the closed condition. Such primary flanges 12b may be mutually constrained, for example, by means of welding (as shown in FIG. 5).

(31) Therefore, the second transverse distance B will depend on the number and/or extension in the transverse direction (with respect to the bulkhead 10) of such flanges 12b.

(32) According to an embodiment of the invention, a sealing element 18 may be interposed between frame 12 (conveniently, at the portion of the first bracket 12a facing the bulkhead) and bulkhead 10, which sealing element 18 may comprise a sealing adhesive and a heat-expanding gasket. According to an embodiment (not shown), such a sealant 18 may be inserted between bulkhead 10 and subframe 14 (conveniently, at the portion of the second bracket 14a facing the bulkhead), alternatively or in addition to the sealant placed between frame 12 and bulkhead 10.

(33) With respect to the prior art, in which the sealing element 18 is compressed between frame 12 and bulkhead 10, the possibility of having a certain clearance between said frame and bulkhead (for example, by broadening the distance A between the facing brackets 12a, 14a), increases the functions of the sealing element. In fact, the heat-expanding gasket, under critical conditions of temperature increase or fire, can freely increase its volume to occupy the entire clearance and ensure the sealing of the joint from the fumes or flames.

(34) The sealing adhesive and heat-expanding gasket of the sealing element 18 synergistically work to meet the requirement of fume and flame resistance, required both in operation as well as for passing the standard fire test in accordance with the Fire Test Procedure of the International Maritime Organization (IMO).

(35) In the first part of the test, i.e. until the connecting joint is at a temperature below 250 C., the sealing adhesive will ensure the joint resistance. For higher temperatures, the sealant could significantly deteriorate and no longer be able to fulfill its function, but for the purposes of the joint sealing, the heat-expanding gasket comes into operation, being able to work from about 200 C. up to the maximum temperatures which are reached at the end of the test. Ultimately, the combined use of sealant and heat-expanding gasket ensures the sealing of the joint, both when the door is mounted on board of the vessel, and for the whole duration of the standard fire test.

(36) By way of example, adhesive materials used for sealing the joint may be silicone-based, even with flame-retardant properties, capable of reaching operating temperatures of up to 250 C. and withstanding temperature peaks of up to 300 C. for limited periods of time. Other adhesive sealants may be, for example:

(37) mono and bi-component polyurethane-based, with flame-retardant properties, suitable to withstand maximum temperatures of up to 150 C.;

(38) based on hybrid polymers, with flame-retardant properties, suitable to withstand maximum temperatures of up to 150 C.;

(39) based on acrylic materials, with flame-retardant properties, suitable to withstand temperatures up to 150 C. and in some formulations with excellent flame reaction properties.

(40) The materials used for manufacturing heat-expanding gaskets usually consist of graphite, or other mineral fibers, which ensure the resistance to high temperatures, and of small percentage amounts of organic materials used to give the system the intumescence function with temperature. Optionally, the sealing element 18 may be made, completely or in part, of an insulating material commercially known as Bifire, the features of which are herein incorporated by reference.

(41) As the fastening assembly 9, comprising frame 12 and subframe 14, is not rigidly connected to bulkhead 10 (or to the additional bracket 22 of structure 20), a high number of connecting joints between frame and subframe is not required, since the forces exchanged are not comparable to the case where such joints directly connect the frame to the bulkhead or to the subframe. Therefore, unlike the conventional solutions, which require a continuous welding over the whole periphery of the door or, for the bolted solutions, the drilling of several holes on the bulkhead (made of steel, aluminum alloy or other metal), in the present invention the mounting operation is easier and less burdensome given the lower number of joining points needed and the possibility of drilling the holes on the frame in the workshop, and not on the bulkhead on board of the ship.

(42) Moreover, a fastening assembly of a door to a bulkhead according to the present invention allows the frame to be protected from the stresses transmitted by the wave load through the bulkhead, and therefore the occurrence of fatigue phenomena or other damages to the frame to be prevented, which phenomena may affect the structural integrity and/or the operational efficiency of the door.

(43) Various aspects and embodiments of the fastening assembly according to the invention have been described. It is understood that each embodiment may be combined with any other embodiment. Moreover, the invention is not limited to the embodiments described, but may be varied within the scope defined by the appended claims.