GB2507016A

GB2507016A - Sealing of passages through walls

Info

Publication number: GB2507016A
Application number: GB1402005.1A
Authority: GB
Inventors: Louis Rey; Benjamin Deve; Eric Bacot
Original assignee: Kaefer Wanner SAS
Current assignee: Kaefer Wanner SAS
Priority date: 2011-07-19
Filing date: 2012-07-19
Publication date: 2014-04-16
Anticipated expiration: 2032-07-19
Also published as: GB201402005D0; WO2013011244A1; FR2978229A1; GB2507016B; FR2978229B1; CN103748394A

Abstract

An installation for sealing passages through walls (100) comprising: - a sealing plug (202) for sealing the space between an internal edge of a wall and a through-part, and - on at least one side of the wall, a thermal insulation sleeve (205) surrounding the through-part over a portion of the length thereof starting from the sealing plug.

Description

Sealing Of Passages Through Walls The invention concerns the sealing of passages through walls.

Some fire-resistant installations provide, at the level of a wall to be passed through, a seal at the level of the elements passing through the wall, for example one or more electrical cables and/or one or more plumbing pipes, etc. The invention may find a particular application in the buildings of nuclear power stations.

It is known to block openings in walls by placing a foam between the element passing through the wall and the edges of the orifice in the wall that this element passes through. Thus a silicone foam can enable a seal to be obtained against water, air or hot gas and can moreover prove simpler to pierce again than concrete or cement in the event of subsequently passing another element through the wall. Nevertheless, in the event of the temperature rising because of a fire on one side of the wall, it has been realized that the temperature on the other side of the wall rises significantly.

There is a need for an installation for passages through walls allowing an improved thermal insulation in order to be able to provide advantageously fire resistance functions and in particular even fire-break properties between two walls.

Fire resistance and/or fire-break standards require installations for sealing passages through walls of improved performance, notably in sensitive buildings, such as nuclear power stations, and factories in the chemical, foodstuffs and other industries.

There is provided an installation for sealing passages through walls comprising: a) a sealing plug for sealing the space between an internal edge of a wall and an element passing through the wall, and b) on at least one side of the wall, a thermally insulative sleeve surrounding the element passing through the wall over a portion of its length starting from the sealing plug.

By "seating the space" is meant that the plug is able to provide sealing, fire resistance and thermal insulation.

Accordingly, the installation for sealing passages through walls is advantageously a fire resistant installation and/or a fire-break installation, for example specifically intended for buildings necessitating a wall temperature to be maintained that is close to the ambient temperature when the other side of the wall is in contact with fire. Moreover, the installation prevents the escape and the passage of gases, notably those liable to be inflammable and therefore to encourage the transmission of fire.

The synergistic combination of the sealing plug and the sleeve enables improved performance to be achieved.

The fire resistant and/or fire-break properties may advantageously be determined by methods as described in the standard NF EN 1363-1. The object of this method is to evaluate the behaviour of a test element of a construction element when it is exposed to defined conditions of heat and pressure. It is therefore possible to test thermal insulation, sealing against tire and smoke, loadbearing capacity, mechanical strength, etc. The insulative sleeve can therefore make it possible to limit the rise in temperature on one side of the wall when the temperature increases on the other side of the wall.

The sleeve can thus make it possible to prevent an external element reaching a high temperature in the event of fire on the other side of the wall.

Because in particular of the presence of a sleeve, the point at which the temperature of the element passing through the wall is measured is offset to a relatively great distance from the wall and so the measured temperatures can remain relatively reasonable even in the case of the temperature rising on the other side of the wall. This prevents the presence of hot spots liable to be in contact with persons or inflammable objects. F, The sleeve therefore makes it possible to confer on the sealing installation properties of thermal insulation of the element passing through the wall that may be quantified in accordance with the standard EN 1363-1. The sleeve advantageously continues to maintain the separation function of the sealing installation without the side of the wall that is not exposed to the fire reaching temperatures that exceed the initial average temperature by more than 140°C, in particular during exposure to fire on the other side of the wall for approximately 2 hours.

The sleeve may be installed on only one side of the wall, and advantageously on both sides of the wall, because it is assumed in most cases that both sides of the wall are liable to catch fire.

A single sleeve may be provided, on only one side of the wall and extending a particular distance from the interior of the passage through the wall or from the sealing plug and/or the wall.

Two sleeves may also be provided, each sleeve corresponding to a respective side of the wall and extending a particular distance from the interior of the passage through the wall or from the sealing plug and/or the wall.

A single sleeve may also be provided extending from one side of the wall to the other. This sleeve may therefore pass through the wall and extend from each side of the wall.

The sleeve advantageously has a thermal conductivity in the range 0.01 to 0.5 W/(m.°C), advantageously in the range 0.02 to 0.2 W/(m.°C), advantageously in the range 0.04 to 0.1 W/(m.°C).

The sleeve may be produced in materials enabling the required performance and notably the above thermal conductivities to be achieved. The materials are preferably chosen in the group consisting of rock wool, mineral fibres, glass wool and silicates.

By from the sealing plug" is meant that the sleeve may be extended toward the interior of the passage through the wall, be in contact with the sealing plug and/or the wall, or be very close to the sealing plug and/or the wall (i.e. 1 centimetre or less therefrom).

The sealing plug may advantageously comprise a shell in an appropriate material installed in the passage through the wall around the element passing through the wall. This shell is clamped using clamping means, for example stainless iron (steel) wire, and may be disposed flush with an upper surface of the wall.

The sealing plug, and in particular the shell, enables the sealing installation to be made fire resistant.

In the case of a temperature rise between 1000°C and 1100°C on one side of the wall for two hours or more, the plug retains its non-powdery solid form and its dimensions, thus enabling it to continue to seal the installation.

Fire resistance may be defined as what provides the mechanical strength of the sealing installation, as determined in particular according to the standard EN 1363-1.

Maintaining the mechanical integrity of the installation of the invention in the event of fire may be defined by the loadbearing capacity in accordance with the standard EN 1363-1. The loadbearing capacity is measured by the ability of a test sample cia loadbearing element to withstand its test load, as necessary, without exceeding specified criteria in respect of amplitude of movement and speed of deformation. The loadbearing capacity may be measured by the time in completed minutes for which the test element continues to maintain its capacity to withstand the load during the tesL The mechanical integrity of the sealing installation is typically considered satisfactory for times of exposure to fire of 2 hours to 6 hours, preferably 2 hours to 4 hours, notably as a function of the materials used.

Moreover, the sealing plug is adapted to enable the sealing installation to maintain the seal between two walls through which the element passes, one of which is exposed to fire. The seal is defined as the seal against hot and cold gases, smoke and fire. The sealing capabilities are determined in particular in accordance with the standard EN 1363-1. The sealing plug is therefore disposed so as to provide the seal between the element passing through the wall and the internal edges of the wall.

The seal may be measured by the hydrophilic cotton pad test from the standard referred to above. The installation is sealed when the hydrophilic cotton pad provided on a support, such as a rod, does not ignite after a few seconds, typically between 1 and 5 seconds, preferably between 2 and 4 seconds. Other standard methods may be used.

The sealing plug also makes it possible to confer on the sealing installation properties of thermal insulation of the internal edge of the wall that may be quantified according to the standard EN 1363-1, as for the sleeve. The sealing plug advantageously continues to maintain the separation function of the sealing installation without the surface of the wall that is not exposed to fire reaching temperatures that exceed the initial average temperature by more than 140°C, in particular during exposure to fire on the other side of the wall for approximately 2 hours.

The sealing plug may have a thermal conductivity selected in the ranges stated above.

Alternatively, the thermal conductivity of the sealing plug may lie in the range 0.05 to 1 Wt(m.°C), advantageously in the range 0.1 to 0.8 W/(m.°C). The sealing plug advantageously contains chemically-bonded water; for example, the ratio between the mass of chemically-bonded water and the total mass of the plug is in the range 0.1 to 0.7, advantageously in the range 0.3 to 0.6, advantageously in the range 0.3 to 0.4.

Without being tied to any particular theory, it is possible that the energy of the fire serves chemical recomposition preceding evaporation. A relatively long evaporation plateau could therefore enable thermal insulation to be provided in the event of fire.

The thermal insulation conferred by the installation for sealing passages through walls on an element passing through the wall is achieved by thermal insulation at the level of the wall and the element passing through the wall.

The sealing plug may advantageously be produced using (these examples are not limiting on the invention): -in mortar, for example GFS 1500 mortar sold by the Applicant, -in silicone foam, in particular a foam produced from silicone oil and a catalyst; there may be cited by way of example Rhodorsil® 1593 foam sold by the company Bluestar Silicones, -in an elastomer, for example Rhodorsil® 1523, -using fibrous panels, for example Wanniflam panels sold by the Applicant, -and/or other materials.

A mastic type, for example silicone, coating may advantageously be applied to the surface of the sealing plug, although this is not limiting on the invention. This can make it possible to obtain improved watertightness. In the event of fire, this mastic layer may be caused to disappear. H The mastic may for example comprise Pyrosil B®.

A woven material coated with mastic, for example with Pyrosil B®, may advantageously be provided, covering the sealing plug, although this is not limiting on the invention. The coated woven material may be glued on, for example using a silicone glue. Means may further be provided to guarantee sealing of the interface between the coated woven material and the wall, for example a bead of Fyrosil B® silicone deposited all around the woven material/concrete interface.

The sleeve may advantageously comprise insulating fibres, for example long high-temperature fibres, for example Insulfrax® fibres sold by the company Unifrax, although this is not limiting on the invention.

The sealing installation advantageously further includes means for mechanical retention of the sleeve, for example a sleeve retaining plate, although this is not limiting on the invention. Because of this mechanical retention, there is avoided the presence of chemical retaining means, of the mineral glue type, for example, for fastening the sleeve to the element passing through the wall. This improves the aging of the sealing installation because mineral glues in fact retain residual water even after several days or even months of drying out. By dispensing with the presence of glue, improved aging of the sealing installation in the medium term, i.e. over a period of five to ten years, is therefore achieved.

The means for mechanical retention of the sleeve may for example comprise iron wires wound around the sleeve or more advantageously two half-shells (for example in stainless sheet metal) that can be assembled to each other, for example by welding them together, or even more advantageously by fixing means, for example screw, clip or other fixing means. The half-shells may occupy the whole of the length of the sleeve or only a portion of the length of the sleeve. In the latter case, the half-shells may for example extend over only a few centimetres or over a few tens of centimetres.

The mechanical retention means may alternatively comprise one or more clamping collars adapted to retain the sleeve.

The invention is therefore in no way limited by the form of mechanical retaining means employed.

The sleeve may alternatively be retained by a glue, for example a silicone glue. A silicone cloth may be wrapped around the sleeve, for example, and fastened using silicone glue.

The length of the sealing sleeve will advantageously be chosen as a function of the required performance, although this is not limiting on the invention.

For example, the sleeve may extend between 200 and 1000 millimetres from the sealing plug or from the end of the sleeve near this plug and/or the wall, advantageously between 300 and 800 millimetres, advantageously between 400 and 750 millimetres.

The thickness of the sealing sleeve will advantageously be chosen as a function of the required performance, although this is not limiting on the invention.

For example, the sleeve may have a thickness between 15 and 60 millimetres, advantageously between 25 and 50 millimetres, advantageously between 30 and millimetres.

The element passing through the wall may for example comprise a mechanical element passing through the wall, for example a metal (for example copper) pipe, for example a plumbing pipe or a pipe for transferring chemical and/or gaseous products. The element passing through the wall may comprise ventilation trunking. The element passing through the wall may comprise an electrical element passing through the wall, for example a cable tray and one or more cables supported by this tray.

There is moreover proposed a method of sealing passages through walls comprising a step of producing a sealing plug providing a seal, resistance to fire and thermal insulation for sealing the space between an element passing through the wall and the internal edges of the wall, and a step of placing a thermally insulative sleeve around the element passing through the wall, over a portion of its length on one or both sides of the wall.

The invention is described in more detail with reference to the appended Figures in which: -Figure 1A shows an example of a mechanical installation in accordance with one embodiment of the invention for sealing a slab, -Figures lB and 1C are sectional views of an installation for sealing the passage through a wall of two closely spaced pipes, respectively at the level of the rock wool shell and at the level of the sleeve, -Figure 2 is a perspective view showing sealing of a passage through a wall with silicone foam and in accordance with another embodiment of the invention, -Figure 3 is a perspective view of sealing the passage through a wall of electrical members with mortar and in accordance with another embodiment of the invention.

Identical references may be used to designate identical or similar objects.

Referring to Figure 1, a concrete wall 100 is pierced by an orifice for passing an element 101 through the wall.

In this example, the waIl 100 is a horizontal concrete slab.

The metal element passing through the wall, for example a steel or copper pipe, is disposed inside the orifice defined in the waIl 100 so as to pass through the shell 103.

A shell 103 of rock wool, for example Rockwool 850 rock wool, 150 mm long and 30 mm thick is cut and installed around the element 101 passing through the wall in the passage through the wall. This shell 103 is clamped with stainless iron (steel) wire. The wall 100 being a slab here, this shell 103 is disposed so as to be flush with an upper surface of the slab.

Shuttering is placed under the slab and around the element 101 passing through the wall under the shell 103 so as to define with the shell 103 and the walls 100 a mould for receiving mortar.

The wall 100 being a slab here, this shuttering is such that the sealing plug 102 reaches the thickness of 150 millimetres and so that the lower face of a shuttering panel, made of polystyrene, for example, is flush with the lower face of the concrete slab.

Mortar is then prepared in order to produce a sealing plug 102.

The support is cleaned so as to be clean and sound. It is then saturated with water using a water spray, for example, after which hydrocentrifugon paint is applied. After a drying time of Ito 24 hours, the GFS 1500 mortar is deposited on the bottom, rising regularly by one level. The mortar is regularly agitated by hand to be sure that the mortar occupies all of the space and that no air bubbles remain.

These operations are repeated until complete and total plugging of the wall opening. In this example, the wall opening has a thickness of approximately 150 mm.

Certain finishing tasks are then carried out. The excess of material may be levelled off and finish smoothing carried out.

The shuttering is removed when the mortar achieves an adequate consistency. H A silicone mastic is applied on top of the shell 103 and also so as to cover the whole of the orifice. The installation therefore includes a silicone mastic part 104 to guarantee watertightness.

In conjunction with the shell 103 and the mastic part 104, the plug 102 seals the space between the element 101 passing through the wall and the internal edges lO9of thewall 100.

There is further disposed around the element 101 passing through the wall a H layer of insulative fibres so as to form a sleeve 105, 105' on either side of the wall.

This sleeve is fixed by means of a retaining plate 106, 106' of a closure flange or retaining plate. For each sleeve part 105, 105' there are two stainless sheet metal half-shells that are fixed together, for example screwed together, to provide the mechanical retention of the sleeve, These shells 106, 106 are extended as flanges 107, 107' adapted to cover the ends of the sleeves 105, 105' opposite the ends of the sleeves in contact with thewau 100.

The sleeves 105, 105' each extend over the same length L. The sleeve 105 extends from the coating 104 while the sleeve 105' extends from the sealing plug 104 and the shell 103. Given the thickness of the shuttering panel, the sleeve 105 therefore has one end situated beyond the plane of the wall surface 110, inside the wall 100.

In the case of a plurality of pipes disposed relatively close to one another, there may be provision for sheathing the whole of this plurality of pipes with rock Figures 1 B and 10 are sectional views respectively at the level of the rock wool shell and at the level of the sleeve of an installation for sealing a passage through a wall with two closely spaced pipes.

Referring to Figure 1B, each of the pipes 101, 151 is surrounded by a C-shaped rock wool shell 103, 153. These shells therefore make it possible to fill the gap between the surfaces tangential to the two pipes and the edge formed by the junction of these two pipes.

Referring to Figure 10, for the portion of the pipes 101, 151 outside the wall and near the wall, i.e. the portion covered with a sleeve here, there may be provided a part serving to fill the empty space between the pipes, this part 108 having a shape suited to this space. For example, the space between the pipes and the planes tangential to the two pipes could be filled with an appropriate insulation 108 after which the sleeve may be installed around the assembly comprising the pipes and the parts 108. The sleeve and the sheet metal protection are therefore common to the two pipes. The sheet metal protection consists of two half-shells 106, 156 and two flanges 107, 157. Each part is assembled using screws that are not shown. The flanges 107, 157 serve to cover the end surface parts of the sleeve not covered by the half-shells 106, 156.

Figure 2 shows the sealing of a mechanical passage through a wall by means of a silicone foam. This time mounting involves a shear wall, i.e. the wall is vertical. The wall 200 is a concrete wall, for example. This wall is first pierced with an orifice for the pipe 201 to pass through after which the pipe 201 is installed on a support system that is not shown. The pipework is fixed using collars the diameter of which is matched to the elements passing through the wall.

A pie-cut polystyrene panel (not shown) is fitted as close as possible to the pipework to serve as the back of shuttering on one of the two faces. Shuttering will be instafled on the other face as the silicone foam is deposited. It may be noted that in the case of a slab, the shuttenng is installed only on the lower face.

Rhodorsil® 1593 silicone foam is prepared by mixing two constituents, a base and a catalyzer, using an electric stirrer. This mixture is degassed in order to eliminate air bubbles for about ten minutes, after which the silicone foam is injected using a pump or a manual or pneumatic gun component into the space defined by the wall 200, the element 201 passing through the wall (possibly sheathed by a shell not visible in Figure 2) and the shuttering (not shown in Figure 2). After a waiting time of the order of 24 hours, the shuttering may be removed. There follow levelling operations using culling tools of the cutter type.

Pyrosil B® silica cloth pre-cut as close as possible to the pipework and having an upper surface projecting at least 40 mm beyond the sealing plug 202 is glued to the concrete frame using a silicone glue. Glue, for example silicone glue 214, is deposited at the periphery of the plug 202 to secure the silicone cloth 204 in place. A 3 mm diameter mastic bead 215 is deposited at the periphery of the concrete-silicone cloth and silicone cloth-pipe interface in order to reinforce the seal.

The silicone cloth is of course applied to the other side of the wall 200.

Once the passage through the wall has been sealed, the mechanical elements 201 passing through the wall are filled with a 38 mm thick blanket sleeve 205 with a density of 160 kg/m3 on each side of the passage through the wall.

This sleeve 205 is temporarily held in place using stainless iron (steel) wires that are not shown.

The dimensions of the sleeves 205 are adapted as a function of the nature of the pipework; for example, in the case of a DN 80 black steel pipe 5.6 millimetres thick, the length of the sleeve may be approximately 500 millimetres on each side of the wall. On the other hand, in the case of a DN 300 black steel sleeve 4 or 12.5 millimetres thick, a 750 millimetres long sleeve will be chosen to clothe the passage through the wall on each side of the wall.

The blanket forming the sleeve 205 may be covered with two stainless sheet metal elements 206 (only one being shown on each side of the wall in Figure 2 to leave the sleeve 205 visible). Each element 206 has the shape of a half-cylinder and ends in flanges 207 at one end. These stainless sheet metal half-cylinders 206 are fixed by stainless screws 4.2 x 13 millimetres that are not shown.

Figure 3 shows an example of passing electrical elements through a wall.

The element 301 passing through the wall thus comprises a cable tray 321 and cables 322 in a vertical pack.

Once again an orifice is pierced in the concrete wall 300. Then hydrocentrifugon paint is applied or not, as a function of the surface state of the interior of the passage through the wall. If the passage through the wall is smooth, this coating is applied.

05 1200 primer is applied to the cables 322 in the sealing treatment area before application of Pyrosil B® silicone. Pyrosil B® silicone is injected into the heart of the cable bundle and between the cables and the cable tray. The cable bundle is reformed and then the cable ties are replaced. A drying time of one hour may be provided. This primer enables a film to be produced on the cables to which the Pyrosil B® adheres.

There then follows the fitting of shuttering, and after that the deposition of blocking mortar, for example GFS 1500 mortar, to form a sealing plug 302. The mortar is deposited starting from the bottom of the space defined by the element passing through the wall, the shuttering and the wall and rising by one level until the wall opening is completely and totally blocked. The thickness of the mortar in the passage through the wall may be approximately 160 mm.

Finishing treatments may be applied, in particular smoothing on one or both sides. This finishing smoothing may if necessary be effected with slight moistening of the support, either by spraying it with water or using a trowel dipped in water.

The Pyrosil B® silicone is then applied at the earliest twelve hours after removing the shuttering. The product is applied to the periphery of the elements passing through the wall as well as to the whole surface using a cartridge gun and a palette knife. The thickness of the Pyrosil B® silicon film 304 may be of the order of 2 mm. A drying time of 72 hours minimum may be provided before a water test.

The Pyrosil B® silicone sealing coating 304 may extend at least 20 rim onto the concrete frame.

Once the passage through the wall has been sealed, the electrical elements 301 passing through the wall are fitted with an insulative fibre thermal protection blanket 305 with a density of 128 kg/m3 and on each side of the passage through the wall over a length of 400 mm or less, for example 300 mm. The length of such sleeves 305 is chosen as a function of the nature of the electrical elements passing through the wall. Each sleeve 305 is then closed on itself.

A covering approximately 1.5 times the thickness of the blanket 305 may be provided with a stainless iron (steel) wire (not shown) enclosed in a silicone cloth 306. The cloth 306 may be glued to itself using silicone glue.

Claims

CLAIMS1. An installation for sealing passages (100) through walls comprising: a) a sealing plug (102, 103, 104, 202, 302) for sealing the space between an internal edge of a wall (109) and an element (101) passing through the wall, and b) on at least one side of the wall, a thermally insulative sleeve (105, 1 05', 205, 305) surrounding the element passing through the wall over a portion of its length starting from the sealing plug.
2. The installation as claimed in claim 1, further comprising a mastic type coating (104; 204; 304) on the surface of the sealing plug (102, 103; 202; 302) to provide watertightness.
3. The installation as claimed in either one of claims 1 or 2, wherein the sleeve (105, 105'; 205; 305) includes insulative fibres.
4. The installation as claimed in any one of claims ito 3, further comprising means (106, 106', 107, 107'; 106, 156, 107, 157; 206, 207) for mechanically retaining the sleeve.
5. The installation as claimed in claim 4, wherein the means for mechanically retaining the sleeve include two half-shells (106, 106'; 106, 156; 206) and fixing means for assembling said half-shells to each other.
6. The installation as claimed in claim 5, wherein the fixing means include screws.
7. The installation as claimed in any one of claims 1 to 6, wherein the portion of the length of the element passing through the wall surrounded by the sleeve (105, 105'; 205; 305) on one or both sides of the wall extends between 200 and 1000 millimetres. -14-
8. The installation as claimed in any one of claims I to 7, wherein the sealing plug (102, 104,202, 302) comprises a shell (103) in contact with the element (101) passing through the wall.
9. The installation as claimed in any one of claims ito 8, wherein the sleeve (105, 105', 205, 305) has a thermal conductivity in the range 0.01 to 0.5 W/(m.°C), advantageously in the range 0.02 to 0.2 Wf(m.°C), advantageously in the range 0.04 to 0.1 W/(m.°C).
10. The installation as claimed in any one of claims ito 9, wherein the sealing plug (102, 103, 104, 202, 302) comprises chemically-bonded water, the ratio between the mass of chemically-bonded water and the total mass of the plug being in the range 0.1 to 0.7, advantageously in the range 0.3 to 0.6, advantageously in the range 0.3 to 0.4.
11. A method for sealing passages (100) through walls comprising: -a step of producing a sealing plug (102, 103, 104, 202, 302) providing a seal, fire resistance and thermal insulation for sealing the space between an element (101) passing through the wall and the internal edges (109) of the wall, and -for at least one side of the wall, a step of placing a thermally insulative sleeve (105, 105', 205, 305) around the element passing through the wall over a H portion of its length starting from the sealing plug.