GB2446868A

GB2446868A - Intumescent device

Info

Publication number: GB2446868A
Application number: GB0703389A
Authority: GB
Inventors: Jonathan Charles Hill
Original assignee: Polypipe Ventilation Ltd
Current assignee: Polypipe Ventilation Ltd
Priority date: 2007-02-21
Filing date: 2007-02-21
Publication date: 2008-08-27
Also published as: GB0703389D0

Abstract

An intumescent device 1 comprises an intumescent material 2 between an inner tube 3 and an outer tube 4, arranged such that the outer tube 4 can be mounted in a support (5, Figure 2) and the inner tube can receive electrical cables or the like 6. The inner and outer tubes may be made of plastic material, and may be coaxial. The plastic material may be PVC, and the tubes may each have a relatively hard skin. The device may be formed by extrusion, and may further be formed integrally by a co-extrusion process. The inner and outer tubes may be of a different colour plastic material. Also claimed is a system for protection against fire comprising the device which is mounted in a conduit connector and passes through an aperture in a fire wall.

Description

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AN INTUMESCENT DEVICE

The invention relates to an mtumescerit device, that is one which has an intumescent materia! usually a rrystallinecornpound which SWCUS on heating.

Such devices are often used in fire prevention or protection as in the case of fire, they swell and can seal off routes along which fire may pass. On the other hand services such as electrical cables or the like, for example wires, fibre optic cables, gas or water pipes are often installed in a building and pass from one room or space ot the building to another through walls. Even when such walls are so-called fire walls, the services have to pass through apertures in the walls, which can be a path for fire transmission from one room or space to another.

It is accordingly an object of the invention to seek to mitigate this disadvantage.

According to a first aspect of the invention there is provided an intumescent device, comprising an intumescent material between an inner and outer tube, the arrangement being such that the outer tube can be mounted in a support, and the inner tube can receive electncal cables or the like.

Thus using the invention, the device can be inserted in a support such as a utility service conduit connector and can pass through a fire wall The inner and outer tubes may suitably be made of plastic material. This provides for ease of manufacture, particularly as the tubes may be coaxial. By "coaxial" is meant one within the other.

The plastic material may preferably be PVC.

The tubes may each have a relatively hard skin. This allows for relatively easy passage of say electrical cables through the inner tube and for relatively easy fitting of the outer tube in a support.

Thus, the outer skin of the outer tube may be relatively hard whereby it is mountable in a SUflI1U such a_s a i;uhIiiui I The tubes may each have a wall thickness of about 0.25mm This provides for as much inner volume for the intumescent material as possible while maintaining the integrity of the device.

The radial distance between the outer surface of the inner tube and the inner surface of the outer tube may be in the range of about 1.5 -2.0mm.

The device may be formed by extrusion, for example by a co-extrusion process, which provides for ease of manufacture. Such a process provides that the inner and outer tubes may be of a different colour plastic material, for example the inner tube may be black and the outer tube red.

According to a second aspect of the invention there is provided a system for protection against fire, comprising a fire wall, a conduit connector and a device as hereinbefore defined mounted in the conduit connector and passing through an aperture in the fire wall.

An intumescent device embodying the invention is hereinafter described, by way of example. with reference to the accompanying drawings Fig. 1 is an end elevational view of a device according to the invention; and Fig. 2 is, to a larger scale, a perspective view of a system incorporating the device of Fig. 1.

Referring to the drawings, there is shown an intumescent device I comprising an intuinescent material 2 between an inner tube 3 and an outer tube 4, the arrangement being that the cuter tube 4 an be mounted in a support 5 such as a conduit support (Fig. 2) and the inner tube 3 can receive electrical cables or the like 6 as hereinbefore defined.

In the ernhndim ent. the!flflCr and cmter tubes 3and 4 are cylindrical and coaxial. ai each has a hard outer surface or skin so that an electrical cable or cables 6 can relatively easily be fed into and through the iimer tube 3, while the outer tube 4 can via its hard outer skin be relatively easily mounted in the conduit support 5, which is itself cylindrical.

The wall thickness of the tubes 3, 4 is about 0.25mm for each one, the radial distance W' between the two tubes 3 and 4 being in the range of 1.5 2.00mm, suitably 1.5mm, to provide as much volume for the intumescent material 2 as possible, for effective fire retardation.

The tubes 3 and 4 are in the embodiment formed by a co-extrusion process and the intumescent matenal 2 is incorporated in the same process so that an integral device I is formed in a single extrusion moulding operation, which will suitably use a 3-mandrel co-extrusion process. This enables the tubes 3 and 4 to be of different colours, such as black for the inner tube 3 and red for the outer tube 4. The material of the tubes 3 and 4 is suitably PVC, though any suitable plastic material could be used.

The device I can be made in any desired length, and cut as required to say a 300mm length.

in use, the device 1 is passed through an aperture 7 in a fire-wall 8 such as a stud wall and is mounted in a conduit support 5 on both sides of the wall 8, only one side being shown in Fig. 2. In the event of fire, the device 1 acts to prevent or retard fire transmission by swelling to seal the aperture 7 and against the electrical cables 6, so preventing fire transmission along plastic electrical conduits, particularly if the inner tube 3 ruptures on expansion of the inti.unescent material 2. A fire protection system 9 is thus provided by the arrangement of Fig. 2.

A two-hour fire penetration integrity rating can be achieved using a device I embodying the invention and as described herein with reference to the drawings

Claims

An intuniescent device, comprising an intumescent material between an inner arid outer tube, the arrangement being such that the outer tube can be mounted in a support, and the inner tube can receive electrical cables or the like.
2. A device according to Claim 1, the inner and outer tubes being of plastic material.
3. A device according to Claim 2, the tubes being coaxial.
4. A device according to Claim 3, the plastic material being PVC
5. A device according to Claim 4, the tubes each having a relatively hard skin.
6. A device according to Claim 5, the outer skin of the outer tube being relatively hard whereby it is mountable in a support.
7. A device according to Claim 5 or Claim 6, the tubes each having a wall thickness of about O.25mm.
8. A device according to any preceding claim, the radial distance between the outer surface of the inner tube and the inner surface of the outer tube being in the range of about 1.5 -2.0mm
9. A device according to any of Claims 2 to 8, formed by extrusion.
10. A device according to Claim 9, formed integrally by a co-extrusion process.
11. A device according to Claim 10, the inner and outer tubes being of a different colour plastic material.
12. An intumescent device, substantially as hereinbefore described with reference to the accompanying drawings.

A system for protection against fire, comprising a fire wail, a conduit connector and a device according to any preceding claim mounted in the conduit connector and passing through an aperture in the fire wall 14. A system for protection against fire, substantially as hereinbefore described with reference to the accompanying drawings.