GB2316613A

GB2316613A - Fire protection container

Info

Publication number: GB2316613A
Application number: GB9710571A
Authority: GB
Inventors: Nigel Christoher Maris; Simon Benedict Jones
Original assignee: Nullifire Ltd
Current assignee: Nullifire Ltd
Priority date: 1996-05-25
Filing date: 1997-05-23
Publication date: 1998-03-04
Anticipated expiration: 2017-05-23
Also published as: FR2748942B1; GB2316613B; FR2748942A1; GB9611018D0; GB9710571D0

Abstract

A fire protection container 106 for a gas bottle 126 e.g. containing liquified propane or butane gas, is made from one or more layers of material, including at least one layer of intumescent material 112, which may be provided on a support of a metal mesh or sheet metal sleeve 114. One or more layers of fire retardant foam 116 may be included, which may be separated by a layer of aluminium foil. A further protective sleeve e.g. of metal such as aluminium, may be provided between the bottle and container wall. The container may be separable into body and lid parts.

Description

2316613 FIRE PROTECTION CONTAINER The invention relates to a fire

protection container for a gas battle.

Gas bottles containing, for example, propane or butane liquified gas are used to supply fuel for cooking and heating appliances for home use, industrial use and camping and caravanning use. The gas bottles maintain the fuel gas under high pressure in its liquified state. Heating such gas bottles in a fire results in an increase in the pressure within the gas bottle, leading to the failure of the regulator valve on the bottle and/or the failure of the gas bottle itse.1f.

This results in an explosion which is of considerable danger to both people and property in the vicinity of the gas bottle.

For this reason, fire services take a considerable amount of care to keep such gas bottles cool in the event of a fire. This results in a diversion of manpower andwater extinguishing power away from other tasks. Conventional containers for gas bottles, such as those attached at the front of mobile caravans, are made of, for example, glass reinforced plastic and are not capable of protecting the gas bottle from a fire to any significant extent.

2 It is therefore an object of the invention to provide a fire protection container for a gas bottle.

According to one aspect of the invention there is provided a fire protection container for at least one gas bottle, wherein the container is made from one or more layers of material, the or at least one layer being a layer of an intumescent heat insulative material In this way, if the container is in a fire, the intumescent material will expand to form a thick heat insulative layer around a gas bottle to be protected.

The fire protection container is preferably for a liquified gas containing bottle, which may contain a liquified fuel gas such as propane or butane.

The fire protection container may include one or more ventilation holes to allow air to circulate around the inside of the container. When gas is drawn from the gas bottle 1Teat from the environment surrounding the gas bottle is used to vaporise liquified gas within the gas bottle. Providing ventilation holes allows heat from the environment to enter the container, thus allowing the liquified gas to efficiently vaporise when the gas within the gas bottle is utilised.

3 A single layer of intumescent heat insulative material may alone constitute the container. Alternatively the layer of intumescent heat insulative material may be supported by a layer of support material.

Preferably the layer of intumescent material is provided on the outer surface of the support material layer. Where the layer of heat insulative material is supported, the thickness of the heat insulative layer is preferably 3 to 8mm. The thickness of the intumescent material layer may vary depending on the amount of fire protection required. Ideally the fire protection container should provide protection for at least 15 minutes to allow opportunity for people within the vicinity of the gas bottle to escape and allow time for the fire brigade 'to arrive and deal with the primary source of the fire. The support material for the intumescent heat insulative material can be any suitable material and is preferably mild steel sheet, expanded steel mesh, wire mesh or glass reinforced plastic. In the latter case, the glass reinforced plastic may be treated to make it flame and/or heat resistant.

An especially preferred form of construction of at least part of the container wall is the use of one or more layers of intumescent material with a metal mesh, 4 such as steel mesh, on or embedded within the or each layer of the intumescent material. The metal mesh provides adequate structural support for the intumescent material whilst having a lower weight than, for example, sheet metal. The or each layer of intumescent material may be 3 to 6 mm thick.

The inside of the container may comprise one or more layers of proprietary fire retardant foam to provide further heat insulation. Where several layers are used they may be separated by at least one layer of heat reflective aluminium foil. Typically, the total thickness of the layer(s) of foam is 10 - 30 mm.

An inner sleeve of metal, such as aluminium, between the or each gas bottle and the container wall, may be provided. This prevents damage to the container wall by movement of the gas bottle during, for example, its removal.

Preferably the intumescent heat insulative material is a sprayable-intumescent epoxy material such as that described in GB 2121056. Intumescent coatings swell when subjected to high temperatures, e.g. in excess of 200C, to form a char that may be up to fifty times the original thickness of a layer. This forms an insulating layer around the container, and also has the advantage that the swollen material fills any gaps in the container, such as any ventilation holes.

Examples of suitable commercially available intumescent material are Firec F444 and System E, which are manufactured by Nullifire Limited, Coventry, CV4 9TJ, United Kingdom.

The intumescent layer may not be arranged to completely surround and enclose a gas bottle and may not cover the base of a gas bottle for example.

The fire protection container may take any suitable form to protect a gas bottle. The fire protection container may be made in at least a separate body portion and a lid portion. The body portion may further be separable into a trunk portion and a base portion. This has the advantage that the amount of weight which needs to be lifted by a person at any one time is reduced. Preferably the portions of the container are securely interlockable, for example by a bayonet connection. Holes for ventilation may be restricted fo one or more of the portions.

To furthe r aid carrying of the fire protection container, one or more carrying handles may be provided. Preferably these are covered with a heat insulative material such as a sprayable intumescent 6 epoxy coating or an intumescent rubber coating.

Alternatively the fire protection container may take the form of a built in or semi-permanent container, such as a substantially rectangular box, attached to, or built into, the structure of, for example, a caravan.

In use the gas battle may be connected to heating or cooking appliances via a hose. The hose may exit the fire protection container via an exit aperture therein. The exit aperture is preferably in the form of an open ended slot so that the gas bottle can be placed in the container with the hose attached, the hose moving along the slot. It is desirable for the open end of the exit slot to be sealable which may be done by any suitable means. Preferably this is undertaken by use of a spring loaded clip which may include a layer of intumescent heat insulative material. When the exit aperture is not in use the spring loaded clip may completely cover the exit aperture. When the exit aperture is in use an edge of the spring loaded clip may contain an indentation to allow the clip to rest securely and seal against the circumference of a gas hose. Alternatively, the exit aperture may simply be sealed in a fire by heat expanded intumescent material.

7 Gas bottles come in a number of different sizes. It is therefore desirable to allow the fire protection container to be used by a number of different sized gas bottles. Preferably one or more internal spacers may be provided to fit within the fire protection container to fit snugly against the gas bottle in use to securely retain the gas bottle and cater for gas bottles of different diameters. The spacers may be in the form of metal bars or shaped inserts. To allow the same exit aperture to be used for different size bottles it is desirable to provide means to allow the gas bottle to be raised or lowered in the container.

Such means may comprise adjustable support means which may be in the form of a tripod with a screw thread adjustable support for the base of a gas bottle.

As indicated earlier, in use, the gas bottle absorbs heat from its surroundings to vaporise the gas within the gas bottle. This results in the gas bottle being colder than the ambient temperature of the surroundings and results in condensation being formed on the surface of the gas bottle. A preferred embodiment of the invention therefore provides a drainage hole in the base of a fire protection 2.5 container to allow any condensation formed upon the gas bottle to drain away.

a According to another aspect of the invention there is provided the combination of a fire protection container according to the previous aspect of the invention with a fire protection sleeve for an outlet hose for a gas bottle.

A further aspect of the invention provides a method of protecting a gas bottle against fire comprising the step of encasing a gas bottle in a fire protection container according to the invention.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which:

Fig. 1 shows a cross-section through a first type of fire protection container in accordance with the embodiment of the invention; Fig. 2 shows a side view of the first type of fire protection container which has been separated into its constituent portions; Figs. 1 and 4 respectively show cross-sections through the wall of the fire protection container of Fig. 1 before and after exposure to heat from a fire; and, Figs. 5 and 6 respectively show detail of a cross-section and a side view of an alternative lid 9 portion and trunk portion arrangement.

Fig. 7 shows a cross-section through an alternative container wall.

Fig. 8 shows a cross-section through a second type of fire prevention container according to the invention.

Fig. 9 shows a simplified expanded view of the main components of the second type of fire prevention container.

Fig. 10 shows a cross-section through a third type of fire prevention container according to the invention.

Fig. 11 shows a simplified expanded view of the main components of the third type of fire prevention container.

Fig. 12 shows details of the lid and hose arrangement of the third type of fire prevention container. Fig. 12a shows a side elevation, Fig. 12b shows a front elevation of a closed container and Fig.

12c shows a partially open container from the front elevation.

The fire protective container 10 of the embodiment is shown in Fig. 1 to contain a gas battle 12 represented by the dotted outline. As shown in Figs. 1 and 2 the container 10 of the embodiment is generally cylindrical and comprises a lid portion 14, trunk portion 16, and base portion 18. The trunk portion 16 is in the form of an open cylindrical tube while the base portion 18 and lid portion 14 are in the form of trays. The lid portion 14 has a lower section 8 which has a reduced diameter or width. This reduced diameter section 8 fits within the upper part of the trunk portion 16, thus giving some structural integrity to the connection, and producing a good seal. An L-shaped slot 6 is provided in the reduced diameter section 8 which co-operates with a lug 5 on the inside of the trunk portion 16 in a bayonet connection. The lid portion 14 is thus secured to the trunk portion 16 by lowering the lid portion 14 onto the trunk portion 16 and rotating the lid portion 14 so that the slot 6 engages the lug 5. The trunk portion 16 and base portion 18 form a similar bayonet connection with the trunk portion 16 including a reduced diameter section 3 to be received by the base portion 18 and the base section 18 including a lug 2 to be received in an Lshaped slot 1 in the trunk section 16.

All of the portions 14,16,18 contain ventilation holes to allow air to circulate around the gas bottle 12, thus allowing the liquified gas to vaporise when required.

Fig. 3 shows a cross-section through the wall of the trunk portion 16 of the container 10. This shows a layer of an intumescent heat insulative material 22 covering the outside surface of a support material 24.

A preferred intumescent heat insulative material is Firec F444, which is available from Nullifire Limited, Coventry, CV4 9W, United Kingdom. The support material 24 is mild steel sheet. Each of the portions 14,16,18 is made from a support 24 and the outer surfaces of the support 24, except for the flat underside of the base portion 18, are coated with a layer of intumescent heat insulative material.

Figs. 1 and 2 show handles 26,28 to enable the portions of the container to be lifted. Two handles 26 are provided on opposite sides of the trunk porticn 16 adjacent the top of the trunk portion 16. Each handle 26 is made of metal and is a U-shape and has screw threaded ends. The ends of the handles 26 are received in apertures (not shown) in the side of the trunk portion 16 and retained by nuts (not shown) inside the container 10. A further handle 28 is provided centrally on the upper surface of the lid portion'1A and is mounted in the same way. A handle has not been provided on the base portion. since this may be attached onto, for example a caravan chassis.

Each handle 26,28 is covered by an intumescent rubber 12 sleeve (not shown). The use of a rubber material aids grip and is more comfortable for a user. The sleeve also prevents heat being transmitted from the handle to the inside of the container.

An aperture 30 is provided in the lid portion 14 to receive a hose 32 (shown in phantom) to conduct gas from the gas bottle 12 out of the container 10 to an appliance. The aperture 30 is in the form of an upright slot intersecting the lower edge of the lid portion 14. With a gas bottle 12 in the body of the container 10 the lid portion 14 can be lowered into place with the hose 32 being received in the slot 30.

The container 10 is provided with a spring loaded clip 34 which completely seals the aperture 30 when not in use. When a gas bottle 12 is placed into the container 10 the clip 34 is slid down by the user against the resistance of the spring (not shown) to open the aperture 30 and allow the hose 32 to be passed therethrough. Upon its release, the clip 34 is forced by the spring against the hose 32. The clip 34 comprises a cut away portion to match the contour of the outer circumference of a hose 32 thus sealing the aperture 30. The clip 34 is coated with an intumescent material, which may be the same material as on the support 24, which will further seal the aperture 30 in the event of a fire. Insulating the 13 hose with a suitable intumescent material, for example, intumescent rubber, provides increased fire protection for the gas supply.

The fire prevention container is intended for use with different sized gas bottles. Spacers 36 in the form of metal angle members are thus provided which may be inserted around the inner surface of the trunk portion 16 to help secure the gas bottle 12 within the container 10. Such spacers 36 are designed so that they do not interfere with the circulation of ventilation air around the gas bottle 12.

A base insert 38 may be provided to adjust the height is of a gas bottle 12 to the level of a hose aperture 30 and thus cater for gas bottles 12 of different heights. The base insert 38 comprises tripod legs 40 supporting a base 42 through an upright adjustable screw threaded rod 44 attached to the base 42 and received in a screw threaded bore in a plate 46 from which the tripod legs 40 depend. A gas bottle 12 is supported on the base 42 in the container 10 and the height of the base 42 is adjustable in relation to the tripod legs 40 by rotating the base 42 to rotate the screw threaded rod 44. For larger gas bottles 12 the base insert 38 would be removed.

14 Tn use, condensation is likely to be formed on the surface of the gas bottle 12. A drainage aperture 48 is therefnre provided in the base portion 18 of the container 10.

When the container 10 containing a gas bottle 12 is in a fire the intumescent heat insula-tive material 2221 will expand in the heat to form a thick heat insulative char layer 50 as shown in Fig. 4 and protect the gas bottle 12 greatly increasing the time to explosion of the gas bottle and hence greatly increasing safety. There is the additional advantage that any holes, such as the ventilation holes 20. are also blocked by the expanded material 50.

is Figs. 3 and 6 show an alternative lid portion and trunk portion arrangement. Only the differences from the first embodiment will be discussed. The container is the same height as in the first embodiment but the trunk portion 52 is taller and includes a rebate 54 at the top of the trunk portion 52 circumferentially around its inner surface. The lug 5 and spring clip 34 are not provided. The lid 56 is not tray shaped as previously but is in the form of a flat disc to sit in the rebate 54 to close the container 10. The slot 6 and az)ertilre 30 thus are not provided on the lid 56. An equivalent aperture 58 for the gas hose is provided within the wall of the trunk portion 52, as shown in Fig. 6. The width of the aperture 59 is smaller than the aperture 30 so that it can be closed in the event of a fire by expanded heat insulative material, thus removing the need for a sealing clip, such as the clip 34.

Fig. 7 shows an alternative form of construction of a container according to the invention. It shows a layer of intumescent material 70, in which is embedded a metal mesh 72, such as steel mesh. This may be formed by spraying an intumescent material. such as an epoxy intumescent onto a metal mesh which has been premoulded to the shape of the container. On the inner surface of the intumescent material are two layers of a proprietary fire retardant foam rubber 74, 76. These are separated by an aluminium foil layer 78 which provides a measure of support for the foam and also helps reflect heat away from the inside of the container.

A metal liner, such as an aluminium liner 80. is preferably provided within the container between the gas bottle (not shown) and foam 74 to protect the foam from accidental damage during removal of the gas bottle.

16 Figs. 8 and 9 show a second type of container 82 according to the invention. This comprises a base 84, trunk 86 and lid 88. The container 82 is generally cylindrical.

The base 84 is circular and made of a metal, stich as aluminium. and is not covered with intumescent material. A gas bottle 90 rests upon chocks 92 which securely hold the bottle 90 on the base 84.

The trilnk 86 is in the form of a hollow cylindpr and it made of a layer of intumescent material 94 upon a metal mesh 96. This has a layer of fire retardant foam 98 on the inside.

The lid comprises a layer of intumescent material 100 on a sheet of metal 102, such as aluminium. The sheet 102 is circular of the same diameter as the trunk 86.

Fire retardant foam 104 is attached to the inner surface of the sheet metal 102. The foam.104 is adapted to the inner surface of the trunk 86 to depend thereinto, The lower surface of the foam 104 is cut to substantially the shape of the top of the gas bottle. 90, thus preventing the spread of heat to the gas bottle 90.

The gas hose (not shown) of the gas bottle 90 passes 17 through an aperture through the trunk 86 wall (not shown). This will be closed by the intumescent material 94 in the event of a fire.

Figs. 10 to 12 show a third type of container 106.

This comprises a metal base 108 which is not covered with intumescent material. A trunk 110 is constructed mainly of intumescent material 1122, metal mesh 114 and fire retardant foam liner 116. A lid 118 is made of intumescent material 120 on sheet metal 1221. with a layer of retardant foam 124 on the inside.

In use, a gas bottle 126 sits upon chocks 128 ort the base 108.

is The trunk 110 comes tip to the shoulder of the gas battle 126 (see Fig. 12a).

The hose 128 of the gas bottle rests upon a rectangular extension 130 to the trunk 110 in a semicircular cutaway 132, in its upper edge which forms one half of aperture 133.

The extension 130 has a layer of sheet metal 131 instead of mesh 114, which is used in the rest of the trunk 110.

is The lid 118 is contoured to the top of the gas bottle 126. The lid 118 is thus in the shape of a truncated cone having a rectangular channel section 134 to receive the upright rectangular extension 130 of the trunk 110. The section 134 of the lid 11.8 is cut away so that the lid 118 fits securely on either side of and on top of the extension 130. A semicircular cutaway 136 is provided in the section 134 to fit the hose 128. This is most clearly shown in Fig. 12c which shows a slightly open container 106.

In the event of a fire the intumescent material 112, 120 is expected to seal the hose aperture.

is In a further embodiment the container may be constructed to enclose more than one gas bottle. More than one base aperture 30 could then be required.

In another embodiment the container 10 may be generally rectangular in cross-section rather than cylindrical. for example similar to the conventional gas cylinder boxes currently found on the front of mobile caravans.

In other embodiments there may be more or fewer ventilation holes than shown in the Figures.

19 In further embodiments the support material 24 may alternatively be mesh, expanded steel mesh or glass reinforced plastic. Other support materials may also be used depending on the use, such as domestic and industrial, to which the fire protection container is to be put.

The invention provides improved safety to the users of gas bottles and to the fire fighters who must tackle fires involving gas bottles.

Claims

C L A I SS

1. A fire protection container for at least one gas bottle, wherein said container is made from one or more layers of material. the or at least one laver being a layer of intumescent material.

2. A fire protection container according to claim 1, additionally comprising one or more ventilation holes to allow air to circulate around the inside of the container.

3. A fire prevention container according to claims 1 or 2, wherein the layer of intumescent is material is supported by a layer of support material.

4. A fire prevention container according to claim 3, wherein the support layer is a layer of metal mesh embedded within. or on a surface of.. the intumescent material.

5. k fire prevention container according to any previous claim. additionally comprisiiig one or more layers of fire retardant foam.

6. A fire prevention container according claim 5, comprising two or more layers of fire retardant 21 foam separated by at least one layer of foil, e.g.

aluminixim foil.

7. A fire prevention container according to anv previous claim comprising, in use, a protective sleeve, e.g. of metal, such as aluminium, between the or each gas bottle and the container wall.

8. A fire prevention container according to any previous claim comprising a separate body portion and lid portion.

9. A fire prevention container according to claim 8, wherein the body portion is separable into a is trunk portion and a base portion.

10. A fire prevention container according to any previous claim, comprising an exit aperture for a gas bottle connector hose. 20

11. A fire prevention container according to any preceding ejaim, wherein height adjustable support means is provided for a gas bottle in the container.

1-2. A fire prevention container according to anv previous claim in combination with a fire protection sleeve for an outlet hose for a gas bottle.

22

13. A method of protecting a gas bottle against fire comprising the step of encasing a gas bottle in a fire protection container according to any preceding claim.

14. A fire prevention container substantially as hereinbefore described with reference to Figs. 1 to 4, to 7, 8 and 9 or 10 to 12.

15. A method of protecting a gas bottle against fire substantially as described herein.