GB1586362A

GB1586362A - Strip seal containing expandable materials

Info

Publication number: GB1586362A
Application number: GB2016876A
Authority: GB
Original assignee: Dufaylite Developments Ltd
Current assignee: Dufaylite Developments Ltd
Priority date: 1977-08-12
Filing date: 1977-08-12
Publication date: 1981-03-18

Description

SPECIFICATION NO. 1586362 The following amendments were allowed under Section 29 on 23 July 1990 Page 1 Line 40 Delete conditions. insert conditions, and in which the base part has a channel section from which the flexible material protrudes and in which the intumescent material is located.

Page 1 Delete Line 64 insert Since the base part page 1 Line 67 Delete located. The insert located, the Page 1 Line 68 Delete then Page 2 Line 123 Delete conditions. insert conditions, and Page 2 Line 124 Delete 2. A seal according to Claim 1 page 2 Line 128 Page 3 Line 4 Delete either of Claims insert Claim Page Line 129 Page 3 Line 5 Delete or 2 Page 3 Line 1 Delete 3 insert 2 Page 3 Lines 7 and 11 Delete 5 insert 4 Page 3 Line 16 Delete 3 or 4 insert 2 or 3 Page 3 Lines 19 and 22 Delete 8 insert 7 Page 3 Line 38 Delete 11 insert 10 For Claims 3 to 12 read 2 to 11 THE PATENT OFFICE 4 September 1990 inhibit the spread of tire.

In the construction of.buildings,walls, floors, ceilings and doors and other movable components are desirably constructed of materials whose fire resistance provides pro-, tection against the spread of-fire from room to room. The inevitable gap around the periphery of a closed door, or other movable building component, even adjacent to the position where a component mates with a debate, in a source of fire-weakness. Fire conditions usually involve some degree of super-atinospheric pressure causing leakage~' through the gap of smoke, noxious gases, and of hot air which can significantly reduce the fire resistance of the door.

By the present invention, there is provided a strip seal for sealing a gap around the periphery of. a door or other movable build ing component, which seal, comprises a base part mountable within. the gap on one side thereof and) carried by the base part, a flexible material constituted and. arranged to extend across the gap to substantially ob- struct gas flow therethrough, and. an intu- mescent material for filling the. gap.. under fire conditions. As the primary application of the strip seal is to the sealing of gaps around doors, reference will be made only to this application in the description which follows. It will beunderstoodhowever that the strip seal may. be. used. in. association with. other movable components as required.

The strip seal is readily mounted within Used alone, an intumescent matenal is not activated early enoughtoprevent the spread of smoke.

In a preferred construction, the, base part has a channel section from which the flexible material protrudes and in which the intumescent material is located. The strip material then has a very neat appearance when fitted and the intumescent material is con cealed or largely concealed, and thereby protected from damage.

As the flexible material, there may be used. a. brush-like material, flexible bristles thereof acting to obstruct the gas flow at low temperatures. Bristles of natural fibre may be employed, but synthetic fibre bristles chosen for their heat resistance are preferred, e. g. polytetrafluoroethylene bristles or bristles of fibrous silicone resin. Bristles treated with flame-proofing agents are suitable in some applications.

Another form of flexible material which may be used is a flexible strip material arranged to extend across the gap from the channel section, Such strip material may have an integral mounting, e. g. a bead or flange for securing it to the base part. A flexible strip material and a flexible material of brush-like character may be used in combination if desired.

The flexible material and the intumescent material may be mounted side by side in the channel. However, it is desirable that the whole width of the channel should be occu (54) STRTP SEAL CONTAINING EXPANDABLE MATERIALS (71) We, DUFAYLITE DEVELOPMENTS LIMITE, a British Company, of Cromwell Road, St. Neots, Cambridgeshire, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement :- The present invention relates to strip seals containing expandable materials.

An object of the present invention is to provide a new and improved arrangement in which an expandable material is used to inhibit the spread of fire.

In the construction of buildings, walls, floors, ceilings and doors and other movable components are desirably constructed of materials whose fire resistance provides protection against the spread of fire from room to room. The inevitable gap around the periphery of a closed door, or other movable building component, even adjacent to the position where a component mates with a rebate is a source of fire-weakness. Fire conditions usually involve some degree of super-atmospheric pressure causing leakage through the gap of smoke, noxious gases, and of hot air which can significantly reduce the fire resistance of the door.

By the present invention, there is provided a strip seal for sealing a gap around the periphery of a door or other movable building component, which seal comprises a base part mountable within the gap on one side thereof and, carried by the base part, a flexible material constituted and arranged to extend across the gap to substantially obstruct gas flow therethrough, and an intumescent material for filling the gap under fire conditions. As the primary application of the strip seal is to the sealing of gaps around doors, reference will be made only to this application in the description which follows. It will be understood however that the strip seal may be used in association with other movable components as required.

The strip-seal is readily mounted within the gap, in a simple operation, to the edge of the door, to the edge of the frame, or to both at different positions around the periphery. By obstructing the gas How, the flexible material obstructs the passage first of smoke and then of heated gas. When the temperature rises, the intumescent material foams, expands and later carbonises forming a seal which tolerates minor distortion of the door and whose fire resistance can be equivalent to that of the door itself. The door may fail first around its periphery, but this failure is delayed.

Used alone, an intumescent material is not activated early enough to prevent the spread of smoke.

In a preferred construction, the base part has a channel section from which the flexible material protrudes and in which the intumescent material is located. The strip material then has a very neat appearance when fitted and the intumescent material is concealed or largely concealed, and thereby protected from damage.

As the flexible material, there may be used a brush-like material, flexible bristles thereof acting to obstruct the gas flow at low temperatures. Bristles of natural fibre may be employed, but synthetic fibre bristles chosen for their heat resistance are preferred, e. g. polytetrafluoroethylene bristles or bristles of fibrous silicone resin. Bristles treated with flame-proofing agents are suitable in some applications.

Another form of flexible material which may be used is a flexible strip material arranged to extend across the gap from the channel section. Such strip material may have an integral mounting, e. g. a bead or flange for securing it to the base part. A flexible strip material and a flexible material of brush-like character may be used in combination if desired.

The flexible material and the intumescent material may be mounted side by side in the channel. However, it is desirable that the whole width of the channel should be occu pied by flexible material to maximise the amount of flexible material available for the sealing. Useful results are obtained by positioning the intumescent material between the flexible material and the base of the ; then, as the flexible material weakens or becomes destroyed as the temperature increases the intumescent material drives it outwardly to replace it progressively.

In the case of a brush-like material used as the flexible material or one of the flexible materials, the bristles thereof preferably extend through the intumescent material. This may be achieved using the intumescent material as the brush backing or as a face of the brush backing. An alternative is to apply the intumescent material to pre-formed brushlike material. For this purpose, an intumescent material of the paint-or mastic-type can be applied through the bristles in admixture with a thinner, allowed to settle to form a layer in contact with the base, and dried.

The following description in which reference is made to the accompanying drawing is given to illustrate the invention. In the drawing : Figure 1 is an elevation of a door fitted in a doorway, Figure 2 is a section on an enlarged scale taken at II-II of Fig. I, and Figures 3 to 7 show five embodiments of a strip seal as provided by the present invention.

Referring to Figs. 1 and 2 an opening 2 in a masonry wall 1 has a conventional lining 3, door stop 4 and architraves 5 and 6 fitted at its vertical sides and top. Hung within the lining 3 is a door 7 hinged at 9 and 10 and opening in the direction of arrow 8 (Fig. 2). The bottom of the door has some clearance with the floor, and its top and sides have some clearance with the door lining. Door stop 4 engages the top and sides of the door when the door is closed, but the fit is incompletely gas-tight.

Fig. 2 shows a gap 11 between the edge of the door 7 and lining 3 within which a strip seal according to the invention is fitted at 12 but not shown in detail in Fig. 2. The strip seal may be fitted around the whole periphery of the door including the bottom.

One form of strip seal is shown in Fig.

3 on a further-enlarged scale. It consists of a channel 13 having its base lined with a strip 14 of intumescent material (which may be a fibrous material impregnated with an intumescent composition) having, outwardly thereof, a brush seal consisting of a base part 15 with a bristle part 16 projecting therefrom. In normal use, the bristle part 16 engages the lining 3 to obstruct gaseous flow.

Under fire conditions, bristle part 16 resists the passage of heated air, which may be smoke-laden. As the temperature rises, e. g. on flames reaching the door, the brush seal yields and the intumescent material foams to seal the gap between the door and the lining. The foam may'replace the brush seal entirely, or may envelop fragments of the seal, the former tending to occur when the brush seal is formed of ! ow-me ! ting thermo- plastic polymeric materials.

Fig. 4 shows another form of the strip seal. In this case, the channel is fitted with strips of the brush material 15,16, and strips of the intumescent material alternating across the width of the channel 13.

In the form of strip seal shown in Fig. 5, the base part 15 of the brush seal extends across the whole width of the channel 13 and the bristle part 16 extends through a layer of intumescent composition 14'of the paint or mastic type applied in admixture with a thinner or solvent and subse quently dried.

With the arrangements of Figs. 4 and 5, the intumescent material is able to foam freely to form a seal for the gap before the brush seal fails.

The strip seal shown in Fig. 6, is similar to that of Fig. 3 except that the brush seal is replaced by a flexible strip material 161 formed as an extrusion with an integral base 17. Strip 161 and its base 17 are formed of thermoplastic material which yields when sufficiently heated to allow intumescent material 14 to foam and seal the gap.

The seal shown in Fig. 7 is similar to that shown in Fig. 5, except that the base part of the brush seal is provided in two parts 15a and 15b, one on each side of a flexible thermoplastic strip material 161 which extends outwardly to substantially the same extent as the bristles 161.

It will be understood that the embodiments of the invention described herein with reference to the drawings are given for purposes of illustration only and that various departures may be made therefrom without departing from the scope of the invention as defined in the following claims.

Claims

WHAT WE CLAIM IS :- 1. A strip seal for sealing a gap around the periphery of a door or other movable building component, which seal comprises a base part mountable within the gap on one side thereof and, carried by the base part, a flexible material constituted and arranged to extend across the gap to substantially obstruct gas flow therethrough, and an intumescent material for filling the gap under fire conditions.
2. A seal according to Claim 1 in which the base part has a channel section from which the flexible material protrudes and in which the intumescent material is located.
3. A seal according to either of Claims 1 or 2 in which the flexible material is brushlike.
4. A seal according to Claim 3 in which the material has bristles of polytetrafluoroethylene or of a fibrous silicone resin.
5. A seal according to either of Claims 1 or 2 in which the flexible material is a flexible strip material.
6. A seal according to Claim 5 in which the flexible strip material has an integral mounting for securing it in the base part.
7. A seal according to any one of Claims 1 to 5 in which the flexible material occupies the whole width of the channel and the intumescent material is located between the flexible material and the base of the channel.
8. A seal according to either of Claims 3 or 4 in which the bristles of the brush-like material extend through the intumescent material.
9. A seal according to Claim 8 in which the intumescent material is the brush backing.
10. A seal according to Claim 8 in which the brush-like material has a base and the intumescent material is of the paint or mastic type which has been applied through the bristles in admixture with a thinner to form a layer.
11. A strip seal for sealing a gap around the periphery of a door or other movable building component, substantially as hereinbefore described and illustrated by reference to the accompanying drawing.
12. A method of sealing a gap around the periphery of a door or other movable building component which comprises applying to the periphery of the door and/or the periphery of the gap a seal according to any one of Claims I to 11.