EP4635578A1

EP4635578A1 - Cast in place firestop device

Info

Publication number: EP4635578A1
Application number: EP24170678.7A
Authority: EP
Inventors: Brendan Voss; Laura Schwabbauer
Original assignee: Hilti AG
Current assignee: Hilti AG
Priority date: 2024-04-17
Filing date: 2024-04-17
Publication date: 2025-10-22
Also published as: WO2025219111A1

Abstract

Cast in place firestop device for installation on corrugated metal decking, comprising an insert, which comprises a flange, a first web for being inserted into a rib of the corrugated metal decking, wherein the first web projects from the flange, and wherein the first web has a first web distal end, and a second web for being inserted into the rib of the corrugated metal decking, wherein the second web projects from the flange, and wherein the second web has a second web distal end, wherein a mouth is formed between the first web distal end and the second web distal end, and a spring-loaded shutter mechanism, wherein the spring-loaded shutter mechanism comprises a first shutter flap pivotably connected to the first web, a second shutter flap pivotably connected to the second web, and at least one thermal fuse for releasing at least one of the first shutter flap or the second shutter flap in case of heat.

Description

The invention relates to a cast in place firestop device for installation on corrugated metal decking.
US2018236280 A1 discloses a fire collar comprising a casing defining a service conduit passage therethrough. The fire collar has an opposing pair of shutters. In use, the shutters are configurable in a non-activated configuration wherein the leading edges are spaced apart so as to make allowance for the service conduit therebetween and when the fire collar is exposed to heat on the activation side in use, the shutters transition to an activated configuration wherein the respective leading edges of the shutters close in the passage.
WO2018193073 A1 discloses a method comprising coupling a platform to a corrugated metal decking, wherein the platform comprises a block-out component configured to conform to a rib of the metal decking; coupling a lead-sleeve to the platform; pouring concrete around the platform and the lead-sleeve, wherein the block-out component blocks a flow of the concrete from below the platform; and inserting a cutting tool through the lead-sleeve to remove one or more portions of the corrugated metal decking to form a through-penetration through the corrugated metal decking.
When installation of a conduit through concreted corrugated metal decking is desired, it is also known to use coring, a method where the required hole is generated by a diamond core drilling machine after the concrete has been poured, or boxing-out, which means the metal deck is cut where the opening should be and boxed out to keep the concrete away from the opening afterwards.
AU2008101 101 A4 discloses a solid rigid cast-in fire collar adaptor for formwork decking.
US2021234350 A1 discloses firestop devices each comprising a housing with an internal passageway for receiving a conduit and an intumescent material that is positioned within the internal passageway.
It is an object of the invention to provide a cast in place firestop device which is, whilst being particular efficient to produce, particularly well suited for larger-diameter quick-melting conduits also.
This object is achieved by a device according to claim 1. Dependent claims refer to preferred embodiments of the invention.
According to the invention, there is provided a cast in place firestop device for installation on corrugated metal decking, comprising

an insert, which comprises a flange, a first web for being inserted into a rib of the corrugated metal decking, wherein the first web projects from the flange, and wherein the first web has a first web distal end intended to face a bottom of the rib, and a second web for being inserted into the rib of the corrugated metal decking, wherein the second web projects from the flange, and wherein the second web has a second web distal end intended to face the bottom of the rib, wherein a mouth, intended for the passage of a conduit, is formed between the first web distal end and the second web distal end, and
a spring-loaded shutter mechanism for closing the mouth in case of heat, wherein the spring-loaded shutter mechanism comprises a first shutter flap pivotably connected to the first web, a second shutter flap pivotably connected to the second web, and at least one thermal fuse for releasing at least one of the first shutter flap or the second shutter flap in case of heat.

The invention is based on the finding that when conventional designs based on intumescent material are used, larger-diameter quick-melting conduits (e.g. conduits having thin walls of polypropylene) might be difficult to seal off at the start of fire testing, in particular when higher pressure is used. This might be due to the intumescent material often being located relatively far away from the bottom of the metal deck, which in term might delay the penetration of heat that is needed to activate the intumescent material, potentially resulting in the intumescent material not being able to expand fast enough to close the void left by the melting conduit.
In essence, the invention builds upon a platform design as described in WO2018193073 A1 , and adds a fire-stopping functionality to the platform itself (which platform is also referred to as "insert" in the present context). The proposed concept uses mechanical design aspects to provide fast closure of the void left by fast melting conduits, preferably without the use of intumescent material (however, additional intumescent material might be provided in certain cases).
The proposed design adds spring loaded shutter flaps on the underside of the platform, wherein the shutter flaps preferably consist of metal, more preferably steel. In normal use, the shutter flaps are held in an upward and open position by the at least one thermal fuse. In case of fire, the at least one thermal fuse releases the upper end of each flap, which in turn releases the spring loading, forcing the shutter flaps to pivot on their respective hinges and closing the opening left by the melting conduit at the mouth. If the conduit has not yet completely melted when the at least one thermal fuse has been activated, the shutter flaps may hit against the remains of the conduit, and the shutter flaps will continue to fall downwards by means of gravity or the dropping of melted conduit material.
Preferably, the spring-loaded shutter mechanism comprises a first compression spring, which abuts, directly or indirectly, against the first web and, directly or indirectly, against the first shutter flap, and a second compression spring, which abuts, directly or indirectly, against the second web and, directly or indirectly, against the second shutter flap. Accordingly, there is a compression spring behind each shutter flap that is held in compression between the respective web and the respective shutter flap when the device is in the non-activated state, thereby biasing the respective shutter flap towards the closed position. This embodiment can be advantageous from a manufacturing and/or operational point of view.
The compression springs can comprise any type of compression spring element. However, it is particularly preferred that at least one of the first compression spring and the second compression spring is a coil spring. Using coil springs for one or all compressions springs can provide particularly good performance at low effort.
According to another preferred embodiment of the invention, the spring-loaded shutter mechanism comprises a first thermal fuse, which, thermally releasably, attaches the first shutter flap to the first web, and the spring-loaded shutter mechanism comprises a second thermal fuse, which, thermally releasably, attaches the second shutter flap to the second web. This can provide particularly efficient operation at low effort. Accordingly, two separate thermal fuses are used. Each of the thermal fuses attaches the respective shutter flap to the respective web, thereby biasing the respective compression spring. When subject to sufficient heat, the respective thermal fuse yields, e.g. by melting, thereby releasing the respective shutter flap to pivot to its closed position, driven by the respective compression spring.
It is particularly preferred that at least one of the first thermal fuse and the second thermal fuse consists of a low melting point material, in particular polypropylene. This can be advantageous from a manufacturing point of view.
Advantageously, at least one of the first thermal fuse and the second thermal fuse is a bolt, in particular a headed bolt, more particularly a double headed bolt. This can allow particularly easy assembly and maintenance.
The insert is preferably monolithic. More preferably, the insert can be a sheet metal part. Both of which can be advantageous in view of manufacturing and/or robustness.
The flange has an outer face that faces away from the mouth. Advantageously, this outer face of the flange is generally flat. This can allow particularly easy attachment of an attachment part, such as a lead-sleeve (which lead-sleeve may be equipped with intumescent material or not).
Advantageously, at least one of the first shutter flap and the second shutter flap is a sheet metal part. This can be advantageous in view of manufacturing and/or robustness.
Advantageously, the first web has generally trapezoidal outline, and/or the second web has generally trapezoidal outline. This can allow particularly effective mounting on trapezoidal metal decking (i.e. meal decking in which the ribs have generally trapezoidal outline). At least one of the webs might be provided with an edge seal for particular good sealing on the corrugated metal decking.
It is particularly preferred that the first shutter flap is pivotably connected to the first web at the first web distal end, and the second shutter flap is pivotably connected to the second web at the second web distal end. This allows optimizing use of the available dimensions, thus reducing material expenditure.
The first compression spring preferably abuts against the first web remote from the first web distal end, and the second compression spring preferably abuts against the second web remote from the second web distal end.
According to another preferred embodiment of the invention, a first knuckle is formed on the first web, and a first pin is formed on the first shutter flap, wherein the first pin projects into the first knuckle, and a second knuckle is formed on the second web, and a second pin is formed on the second shutter flap, wherein the second pin projects into the second knuckle. This can provide particularly easy to manufacture pivotable connections of the respective shutter flap to respective web.
The invention is explained in greater detail below with reference to preferred exemplary embodiments, which are depicted schematically in the accompanying drawings. Individual features of the exemplary embodiments presented below can be implemented either individually or in any combination within the scope of the present invention.

Figure 1 is a first perspective view of a cast in place firestop device, with the shutter mechanism in a non-activated configuration.
Figure 2 is a perspective view, similar to that of figure 1, of the device of figure 1, with the shutter mechanism in an activated configuration.
Figure 3 is a second perspective view of the device of figure 1, with the shutter mechanism in the non-activated configuration.
Figure 4 is a perspective view, similar to that of figure 3, of the device of figure 1, with the shutter mechanism in the activated configuration.
Figure 5 is a front view of the device of figure 1, with the shutter mechanism in the non-activated configuration.
Figure 6 is a front view of the device of figure 1, with the shutter mechanism in the activated configuration.
Figure 7 is a bottom view of the device of figure 1, with the shutter mechanism in the non-activated configuration.
Figure 8 is a bottom view of the device of figure 1, with the shutter mechanism in the activated configuration.
Figure 9 is a side view of the device of figure 1, with the shutter mechanism in the non-activated configuration.
Figure 10 is a side view of the device of figure 1, with the shutter mechanism in the activated configuration.

The figures show an embodiment of a cast in place firestop device. The device comprises a metal decking insert, which is intended to be inserted into a rib of a corrugated metal decking, in particular into a rib of a trapezoidal metal decking. The insert comprises a generally trapezoidal first web 11 and a generally trapezoidal second web 12, as well as a flange 10 that connects the first web 11 and the second web 12 with one another, in an aligned configuration. The insert is a sheet metal part, and accordingly, the first web 11, the second web 12 and the flange 10 are monolithic. Each of the first web 11, the second web 12 and the flange 10 is a generally flat sheet. The first web 11 and the second web 12 extend parallel to one another, and their trapezoidal outlines are aligned with one another, so that both the first web 11 and the second web 12 can fitted into the rib of the trapezoidal metal decking. The first web 11 and the second web 12 both project from the flange 10, in each case in a generally orthogonal relationship with respect to the flange 10.
The first web 11 has a first web distal end 13, which is an end located remote from the flange 10 and/or diametrically opposite the flange 10 on the first web 11. The first web distal end 13 is intended to face a bottom of the rib of the corrugated metal decking when the insert is fitted into the rib as intended. Likewise, the second web 12 has a second web distal end 14, which is an end located remote from the flange 10 and/or diametrically opposite the flange 10 on the second web 12. The second web distal end 14 is intended to face a bottom of the rib of the corrugated metal decking when the insert is fitted into the rib as intended. Each one of the first web distal end 13 and the second web distal end 14 is a free end.
A mouth 9 is formed between the first web distal end 13 and the second web distal end 14. This mouth 9 is intended to face a bottom of the rib of the corrugated metal decking and to be located adjacent to said bottom of the rib when the insert is fitted into the rib as intended. The mouth is intended for the passage of a conduit into the insert.
The flange 10 has an outer face 19 that faces away from the mouth 9, wherein this outer face 19 of the flange 10 is generally flat. A lead-sleeve, in particular a lead-sleeve provided with an intumescent material, might be attached to said outer face 19, as will be described in more detail further below.
The device furthermore comprises a spring-loaded shutter mechanism for closing the mouth 9 in case of fire. The shutter mechanism comprises a first shutter flap 21 that is pivotably connected to the first web 11, namely by means of a first hinge. In particular, the first hinge is provided adjacent to the first web distal end 13. In the shown embodiment, the first hinge comprises two first knuckles 51 that are formed, in particular monolithically, on the first web 11, and two first pins formed, in particular monolithically, on the first shutter flap 21, wherein each of said first pins protrudes into one of said first knuckles 51. Other types of hinges are, however, also feasible.
Likewise, the shutter mechanism comprises a second shutter flap 22 that is pivotably connected to the second web 12, namely by means of a second hinge. In particular, the second hinge is provided adjacent to the second web distal end 14. In the shown embodiment, the second hinge comprises two second knuckles 52 that are formed, in particular monolithically, on the second web 12, and two second pins formed, in particular monolithically, on the second shutter flap 22, wherein each of said second pins protrudes into one of said second knuckles 52. Other types of hinges are, however, also feasible.
The shutter mechanism further comprises a first compression spring 41, which can in particular be a coil spring. This first compression spring 41 abuts, on its one side, against the first web 11, and abuts, on its other end, against the first shutter flap 21. The first compression spring 41 biases the first shutter flap 21 towards a closed position in which the first shutter flap 21 closes the mouth 9. Likewise, the shutter mechanism comprises a second compression spring 42, which can in particular be a coil spring. This second compression spring 42 abuts, on its one side, against the second web 12, and abuts, on its other end, against the second shutter flap 22. The second compression spring 42 biases the second shutter flap 22 towards a closed position in which the second shutter flap 22 closes the mouth 9.
The spring-loaded shutter mechanism furthermore comprises a first thermal fuse 31. This first thermal fuse 31 is a bolt, in particular a double-headed bolt, which extends through both the first web 11 and the first shutter flap 21, and thereby holds the first shutter flap 21, against the bias of the first compression spring 41, in an open position, in which the first shutter flap 21 is adjacent to the first web 11 and roughly parallel thereto. When subjected to fire heat, the first thermal fuse 31 yields (e.g. by melting), thereby releasing the first shutter flap 21 to pivot, driven by the first compression spring 41, into a closed position in which it closes the mouth 9. Likewise, the spring-loaded shutter mechanism comprises a second thermal fuse 32. This second thermal fuse 32 is a bolt, in particular a double-headed bolt, which extends through both the second web 12 and the second shutter flap 22, and thereby holds the second shutter flap 22, against the bias of the second compression spring 42, in an open position, in which the second shutter flap 22 is adjacent to the second web 12 and roughly parallel thereto. When subjected to fire heat, the second thermal fuse 32 yields (e.g. by melting), thereby releasing the second shutter flap 22 to pivot, driven by the second compression spring 42, into a closed position in which it closes the mouth 9.
When used as intended, the insert is fitted into the rib of the metal decking insert, so that the first web 11 and the second web 12 fit into the rib. A lead-sleeve, in particular provided with an intumescent material in its interior, might be attached to the flange 10. Concrete is then poured onto the metal deck, and the webs 11 and 12, which might optionally be provided with edge seals, prevent the concrete from entering the inside of the insert. Aligned through holes are provided in the flange 10 and the corrugated metal decking, e.g. by drilling through the lead-sleeve after the concrete has been poured, and a conduit is passed through said through holes and, optionally, through the lead-sleeve. All this is done with the shutter mechanism in the non-activated configuration (as shown in figures 1, 3, 5, 7 and 9), i.e. with both the first shutter flap 21 and the second shutter flap 22 held open (i.e. generally close to the first web 11 and the second web 12, respectively) by the first thermal fuse 31 and the second thermal fuse 32, respectively.
In case of a subsequent fire, the heat emerging from the fire will break the first thermal fuse 31, thereby pivotably releasing the first shutter flap 21, and the first compression spring 41 will then urge the first shutter flap 21 into its closed position so as to close the mouth 9. Likewise, the heat emerging from the fire will break the second thermal fuse 32, thereby pivotably releasing the second shutter flap 22, and the second compression spring 42 will then urge the second shutter flap 22 into its closed position so as to close the mouth 9. The resulting activated configuration of the shutter mechanism is shown in figures 2, 4, 6, 8 and 10.

Claims

Cast in place firestop device for installation on corrugated metal decking, comprising
- an insert, which comprises a flange (10), a first web (11) for being inserted into a rib of the corrugated metal decking, wherein the first web (11) projects from the flange (10), and wherein the first web (11) has a first web distal end (13) intended to face a bottom of the rib, and a second web (12) for being inserted into the rib of the corrugated metal decking, wherein the second web (12) projects from the flange (10), and wherein the second web (12) has a second web distal end (14) intended to face the bottom of the rib, wherein a mouth (9), intended for the passage of a conduit, is formed between the first web distal end (13) and the second web distal end (14), and

- a spring-loaded shutter mechanism for closing the mouth (9) in case of heat, wherein the spring-loaded shutter mechanism comprises a first shutter flap (21) pivotably connected to the first web (11), a second shutter flap (22) pivotably connected to the second web (12), and at least one thermal fuse (31, 32) for releasing at least one of the first shutter flap (21) or the second shutter flap (22) in case of heat.
Device according to claim 1,
characterized in that
the spring-loaded shutter mechanism comprises a first compression spring (41), which abuts against the first web (11) and against the first shutter flap (21), and a second compression spring (42), which abuts against the second web (12) and against the second shutter flap (22).
Device according to claim 2,
characterized in that
at least one of the first compression spring (41) and the second compression spring (42) is a coil spring.
Device according to any of the preceding claims,
characterized in that
the spring-loaded shutter mechanism comprises a first thermal fuse (31), which, thermally releasably, attaches the first shutter flap (21) to the first web (11), and

the spring-loaded shutter mechanism comprises a second thermal fuse (32), which, thermally releasably, attaches the second shutter flap (22) to the second web (12).
Device according to claim 4,
characterized in that
at least one of the first thermal fuse (31) and the second thermal fuse (32) consists of polypropylene.
Device according to any of claims 4 or 5,
characterized in that
at least one of the first thermal fuse (31) and the second thermal fuse (32) is a bolt.
Device according to any of the preceding claims,
characterized in that
the insert is monolithic.
Device according to any of the preceding claims,
characterized in that
the insert is a sheet metal part.
Device according to any of the preceding claims,
characterized in that
the flange (10) has an outer face (19) that faces away from the mouth (9), wherein the outer face (19) of the flange (10) is generally flat.
Device according to any of the preceding claims,
characterized in that
at least one of the first shutter flap (21) and the second shutter flap (22) is a sheet metal part.
Device according to any of the preceding claims,
characterized in that
- the first web (11) has generally trapezoidal outline, and

- the second web (12) has generally trapezoidal outline.
Device according to any of the preceding claims,
characterized in that
- the first shutter flap (21) is pivotably connected to the first web (11) at the first web distal end (13), and

- the second shutter flap (22) is pivotably connected to the second web (12) at the second web distal end (14).
Device according to any of the preceding claims,
characterized in that
- a first knuckle (51) is formed on the first web (11), and a first pin is formed on the first shutter flap (21), wherein the first pin projects into the first knuckle (51), and

- a second knuckle (52) is formed on the second web (12), and a second pin is formed on the second shutter flap (22), wherein the second pin projects into the second knuckle (52).