GB2285947A

GB2285947A - A method and apparatus for insulating a hollow member

Info

Publication number: GB2285947A
Application number: GB9401671A
Authority: GB
Inventors: Michael Gwyn Williams
Original assignee: Catnic Ltd
Current assignee: Catnic Ltd
Priority date: 1994-01-28
Filing date: 1994-01-28
Publication date: 1995-08-02
Anticipated expiration: 2014-01-28
Also published as: GB2285947B; GB9401671D0

Abstract

For thermally insulating a hollow member such as a metal lintel (2, 3) by filling its interior (9) with expansible material such as polystyrene, the interior is closed off by a plate (12) with flexible seal means (13) which accommodate variations in spacing (x) at the mouth of the interior of the lintel so that the expansible insulating material is enabled to substantially close that mouth on expansion. <IMAGE>

Description

A METHOD AND APPARATUS FOR INSULATING A HOLLOW MEMBER The invention relates to a process of and apparatus for insulating a hollow member, and to a hollow member, such as a metal lintel insulted by the process and apparatus.

Modern environmental considerations often require that a hollow member such as lintel installed in a cavity wall be insulated, using a thermal insulating material, so as to seek to avoid thermal bridging between inner and outer leaves of a cavity wall in which in use the lintel is to be installed. Inserting a pre-formed block of insulating material has been proposed, but such blocks are difficult to insert, easily fall out and in any event do not provide a sound insulation. Inserting blocks can be time-consuming and thus expensive, and methods of forming insulation in situ have also been proposed. However, lintels are not engineered to high degrees of tolerance dimensionally, so it has been difficult to provide an efficient process and apparatus for in situ insulation.

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

According to a first aspect of the invention there is provided a process of insulating a hollow member which has a variable spacing between opposed parts defining a mouth of the hollow member, comprising providing a device to close the mouth, providing expansible material which is adapted to provide insulation in the hollow member, providing means to expand the insulating material and providing seal means whereby when the hollow member, device and seal means are combined, the seal means accommodates variations in spacing between opposed parts defining the mouth whereby the mouth is substantially closed during expansion of the insulating material.

The process may provide insulating material which is expansible on application of heat. This is a relatively readily controllable process, particularly where steam is used. The closing device and seal means may be provided as an integral unit. This again provides for process control.

The seal means may have at least a boundary which is flexible, and may also preferably be resilient. This provides for ready accommodation of irregularities and/or dimensional variations in the hollow member.

The seal means may suitably comprise a flexible tubular member.

The process may comprise passing steam through the closing device. This provides a compact structure for carrying out the process.

A desired surface profile may be provided on the insulating material at or adjacent the mouth during expansion. This process step provides a desired surface finish.

According to a second aspect of the invention there is provided apparatus for carrying out the process as hereinbefore defined, comprising a device for closing the mouth and seal means with which the closing device closes the mouth and accommodates variations in spacing between the opposed parts defining the mouth whereby the mouth is substantially closed.

The closing device may comprise conduit means for passage of a heating medium into the hollow member in use. This provides a compact structure.

The closing means and seal means may be integral. This again provides a compact, and relatively simple structure.

The seal means may be flexible, and, preferably resilient. This provides for accommodation of structural irregularities and dimensional variations, particulary where the seal means may comprise a tubular member.

The tubular member may comprise a rubber or rubber-like material. This is relatively inexpensive.

The seal means may comprise two substantially parallel, spaced apart parts.

This arrangement is suitable for closing a mouth defined by opposite substantially straight walls of say a metal lintel.

The parts may be housed in a respective housing of the closing device. The housing may each comprise a substantially channel-shaped housing removably carried by the closing device. This provides for compactness, particularly where the housings are mounted in the device, and for ease of maintenance.

The housings may comprise a retaining means for retaining the respective seal means part. This provides for ease of construction, particularly where the retaining means may comprise a lip extending from one limb of the channel towards the other.

According to a third aspect of the invention there is provided a hollow member, whenever insulated using a process or apparatus as hereinbefore defined.

The hollow member may comprise a metal lintel, and the insulating material may comprise polystyrene. This provides a thermally insulated lintel.

The polystyrene may be partially expanded before entry into the lintel.

The polystyrene may be injected into the lintel in a stream of carrier fluid such as air. This provides for ease of filling.

The lintel may be formed in one piece.

A process apparatus and hollow member according to the invention are hereinafter described, by way of example, with reference to the accompanying drawings.

Figure 1 shows schematically a process and apparatus according to the invention for thermally insulating a hollow member such as a metal lintel.

Figures 2A and 2B show details of the process and apparatus according to the invention; and Figure 3 shows a transverse sectional view of a lintel insulated using a method and apparatus according to the invention.

Referring to the drawings, in which like parts are referred to by like reference numerals, a metal lintel 1 for bridging a cavity between two (inner and outer) skins of a cavity wall (not shown) has bottom (in use) plates 2, 3 which are directed away from each other and sit respectively in the inner and outer skin, or leaf, of the wall. The plates 2, 3 are connected by a member 4 which in use sits in the cavity, and bridges it, the sloping 5 part providing a damp-proof course or water shedding member which directs moisture condensing in the cavity to the outside leaf and hence to the exterior of a building of which the wall forms a part. In Figure 1, the lintel 1 is formed in one piece by a suitable metal forming operation. In Figure 3, the lintel 1 is formed from two substantially L-shaped members which are secured at the top (as viewed) by a suitable connection 4. In either embodiment, the lintel 1 is a hollow member, and, to provide a thermal insulation or "break" so that the inner skin of the wall is not locally cooled where the lintel is positioned, leading to problems of plaster cracking or damp formation, the lintel is required to be insulated with a suitable thermal insulation material 6, which must of necessity be light. It will be appreciated, however, that a lintel 1 is not a highly engineered product, all that is essentially being required is that the spacing between plates 7, 8 defining the hollow interior 9 of the members are of a spacing such that they can be received in a standard cavity of the wall. The wall itself will not be strictly geometrically constructed by bricklayers, so the lintel 1 is not, as stated, highly engineered. In practice this means that there can be a variable spacing between opposed parts 10 defining a mouth 11 of the hollow member in this case the spacing between the parts of the plates can therefore vary, for example by 6MM or more horizontally as shown at 'x' Figure 2B. It will also be understood that there can be a vertical variation in dimension too.

If therefore it is desired to insulate the hollow member, or lintel, using a moulding process, it is necessary to accommodate these dimensional variations. In a process and apparatus embodying the invention, this is achieved by providing a device 12 for closing the member which has seal means 13 which when the lintel, device, and seal means are combined can accommodate such variations in spacing in opposed parts defining the mouth 11 whereby the mouth 11 is substantially closed during expansion of insulating material.

The seal means 13 is resilient and comprises two parts which are substantially parallel elongated tubular members of rubber or rubber-like material. The parts 13 are each housed in a channel-shaped housing 14 in the closing device 13 which itself is in the form of a closing plate or plates. The housings 14 each have an inwardly projecting lip 15 to retain the tubular seal part 13 in position. The housings 14 are themselves removably mounted in the plate 12 by securing means such as bolts 16.

In use to provide a thermal insulation in the lintel 1, the lintel 1 is placed in a mould and held by mould parts 17, 18 against the upright members 7, 8, the lintel being inverted as shown. Granules or particle of expansible insulating material are placed in the hollow interior of the lintel 1 the end of which are closed by end plate (not shown) of the moulding apparatus. The closing device 12 is then offered up to the open mouth 11 so that the tubular seal parts impinge on the transition parts 10 and deform to provide a complete seal. This is shown in Figure 2A. In Figure 2B, there is again a complete seal even with an irregularity of say 6MM, 'x' in Figure 2B, the variation being accommodated by the flexible seal parts 13.

In either embodiment, the expansible insulating material 6 is expanded by steam passing into the lintel through a conduit 17. The particles, which may be of pre-expanded polystyrene, expand, and stick to each other and to the lintel 1. The insulating material thus is secured in position by being fused to the material of the lintel. Thus this exposed face at the mouth of the lintel, which may be profiled as shown in Figure 3 by having a closure device which has a suitable surface profile 18 provides a key for material such as plaster.

The insulating material 6 may be beads of polystyrene typically 0.2 to 3.0MM in diameter, containing say 6% pentane expansion medium. A small amount of a bromide compound may be present in fire retardant applications.

The particle may be carried into the hollow interior of the lintel in a stream of fluid such as air.

Claims

1. A process for insulating a hollow member which has a variable spacing between opposed parts defining a mouth of the hollow member, comprising providing a device to close the mouth, providing expansible material which is adapted to provide insulation in the hollow member, providing means to expand the insulating material and providing seal means whereby when the hollow member, device and seal means are combined, the seal means accommodates variations in spacing between opposed parts defining the mouth whereby the mouth is substantially closed during expansion of the insulating material.

2. A process according to Claim 1, comprising providing insulating material which is expansible on application of heat.

3. A process according to Claim 2, comprising contacting the material with steam.

4. A process according to any preceding claim, comprising providing the closing device and seal means as an integral unit.

5. A process according to Claim 4, the seal means having at least a boundary which is flexible.

6. A process according to Claim 5, the seal means being resilient.

7. A process according to Claim 6, the seal means comprising a flexible tubular member.

8. A process according to any of Claims 3 to 7, comprising passing steam through the closing device.

9. A process according to any preceding claim, comprising providing a desired surface profile on the insulating material at or adjacent the mouth during expansion.

10. A process for insulating a hollow member which has a variable spacing between opposed parts defining a mouth of the hollow member, substantially as hereinbefore described with reference to the accompanying drawings.

11. Apparatus for carrying out the process of Claim 1, comprising a device for closing the mouth and seal means with which the closing device closes the mouth and accommodates variations in spacing between the opposed parts defining the mouth whereby the mouth is substantially closed.

12. Apparatus according to Claim 10, the closing device comprising conduit means for passage of a heating medium into the hollow member in use.

13. Apparatus according to Claim 11 or Claim 12, the closing means and seal means being integral.

14. Apparatus according to Claim 13, the seal means being flexible.

15. Apparatus according to Claim 14, the seal means being resilient.

16. Apparatus according to Claim 15, the seal means comprising a tubular member.

17. Apparatus according to Claim 16, the tubular member comprising a rubber or rubber-like material.

18. Apparatus according to Claim 17, the seal means comprising two substantially parallel, spaced apart paths.

19. Apparatus according to Claim 18, the parts being housed in a respective housing of the closing device.

20. Apparatus according to Claim 19, the housings each comprising a substantially channel-shaped housing removably carried by the closing device.

21. Apparatus according to Claim 20, the housing comprising a retaining means for retaining the respective seal means part.

22. Apparatus according to Claim 21, the retaining means comprising a lip extending from one limb of the channel towards the other.

23. Apparatus for insulating a hollow member which has a variable spacing between opposed parts defining a mouth of the hollow member, substantially as hereinbefore described with reference to the accompanying drawings.

24. A hollow member, whenever insulated using a process according to any of Claims 1 to 9 or apparatus according to any of Claims 10 to 23.

25. A hollow member according to Claim 24, comprising a metal lintel.

26. A hollow member according to claim 25, the insulating material comprising polystyrene.

27. A hollow member according to Claim 26, the polystyrene being partially expanded before entry into the lintel.

28. A hollow member according to either of Claims 26 or 27, the polystyrene being injected into the lintel in a stream of carrier fluid.

29. A hollow member according to claim 28, the fluid comprising air.

30. A hollow member according to any of Claims 24 to 29, comprising one piece.

31. A hollow member such as a metal lintel, substantially as hereinbefore described with reference to the accompanying drawings.