AU2005202669B2

AU2005202669B2 - Fireproofing cover and intumescent material for heat sink

Info

Publication number: AU2005202669B2
Application number: AU2005202669A
Authority: AU
Inventors: Hongzhen Wei
Original assignee: Individual
Current assignee: Individual
Priority date: 2005-04-13
Filing date: 2005-06-20
Publication date: 2012-07-26
Anticipated expiration: 2025-06-20
Also published as: AU2005202669A1; GB2425059B; CN1676178A; GB2425059A; CN1676178B; GB0513296D0

Abstract

Abstract The present invention provides a fireproofing cover and a special intumescent material for its heat sinks. The fireproofing cover can stop fast spreading of fire, 5 causing flame to have no burning conditions and go out by itself. The present fireproofing cover includes the cover top, bevel edge, cover enclosure and cover skirt. On the bevel edge there are the heat sinks. The heat sinks are made up of two layers: the intumescent piece underlayer 10 and the ceramic fiber paper upper layer. The cover top, bevel edge, cover enclosure and cover skirt are made of the glass fiber cloth, one side of which is surfaced with fireproofing coat capable of resisting high temperature. Inside the cover enclosure there is an inner cover support 15 bracket. On the cover enclosure there is a mounting support. The special intumescent piece for the said heat sink uses the ceramic fiber, 32-mesh expandable graphite and polyvinyl alcohol as the main raw materials. And the 32-mesh expandable graphite has a content of 20%-50% in 20 the material. The special intumescent piece for the heat sinks used on the fireproofing cover of the present invention has an excellent expansion performance, and it can completely and instantly seal the air holes on the heat sinks of the fireproofing cover as to achieve the 25 goal of extinguishing fire automatically. H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05

Description

P/00/0Il Regulation 3.2 AUSTRALIA PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT Name of Applicant: Hongzhen WEI Address of Applicant: Room 1002, No. 53 Lane 500, Xiang Yin Road Shanghai 200433 China Actual Inventor: Hongzhen WEI Address for Service: Griffith Hack, Patent and Trade Mark Attorneys, 6th Floor, 256 Adelaide Terrace, Perth, Western Australia, 6000. Standard Complete Specification for the invention entitled: FIREPROOFING COVER AND INTUMESCENT MATERIAL FOR HEAT SINK Details of Basic Convention Application: Chinese Application No. 200510064302.6 Application Date: 13 April 2005 The following is a full description of this invention, including the best method of performing it known to me:- -2 Fireproofing Cover and Intumescent Material for Heat Sink Technical Field The present utility model relates generally to a protection device for electric lighting appliances and the special 5 material for its heat sinks and, more particularly, to a fireproofing cover for electric parts of lighting fittings and the special material for its heat sinks. The fireproofing cover is designed to control the inflammation resulting from the inflammables which are emblazed due to 10 the electric sparks produced by the short circuited electric wires or appliances or poor contact, and it can stop fast spreading of fire, thus causing flame to lack the combustion conditions and go out by itself. 15 Background Art In the existing interior decoration of housings, the tail parts of the lighting fittings and the electrical parts (including the wire connection and electrical fittings, e.g. rectifier, transformer, trigger, and capacitor, etc.) 20 are normally hidden and left naked behind the panels (for example, the suspended ceiling panel, wall protection panel, etc.) . So, once the wires or parts/components of the appliances are short circuited or in poor contact to produce electric sparks, it is very liable to light up the 25 inflammables around the electric appliances as to lead to combustion, thereby resulting in fire accident. Particularly, in some public places such as large singing halls, dancing halls, markets, conference halls and cinemas as well as wood-framing residences, fire accidents occur 30 now and then due to the lighting facilities, leading to an extreme serious impairment and damage. H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 - 3 Though the broad public has had a common understanding on such disasters as resulted thereof and taken necessary measures, no product so far can hold back the spread of fire completely and efficiently as to achieve the goal of 5 extinguishing flame. Summary of the Invention In one aspect the invention provides a fireproofing cover comprising a cover body on which there are heat sinks with 10 air holes, the heat sinks being formed from two layers comprising an intumescent piece underlayer and a ceramic fiber paper upper layer. In one embodiment the intumescent material piece is covered 15 with high temperature resistant (temperature resistance of >1000 0 C) ceramic fiber paper to ensure the intumescent material to go expanded laterally. The said cover body includes the cover top, bevel edge, 20 cover enclosure and cover skirt. On the bevel edge there is fitted the heat sinks available with a number of air holes. The said cover top, bevel edge, cover enclosure and cover skirt are made of the glass fiber cloth material, on one 3426229_1 (GHMatters) P57249.AU 8/06/12 - 4 side of which is painted the fireproofing coat capable of resisting the temperature as high as >750 0 C, forming a sealed cylinder body. Inside the cover enclosure, the inner cover support bracket is provided. 5 The cover enclosure of the said fireproofing cover is linked with the mounting support that is provided with the mounting holes. 10 The fireproofing cover can be made into square, rectangular, arch or any other shapes depending on the different shapes and sizes of the lighting fittings and their electrical parts. The fireproofing cover can be easily mounted at the different locations through the mounting holes on the 15 mounting support. The operating principle of the present invention is described below. The most of the possible causes of fires due to the electrical appliances are resulted from the short 20 circuit or poor contact of the naked electric wires and other electrical parts and components, which produces the electric sparks and lights up the inflammables around the electrical appliances. In light of the aforesaid cases, there needs a kind of product which is able to make the 25 burning electrical appliances not to get contact with the surrounding articles and air as far as possible, in an attempt to control the burning area within a given range, hold back the burning speed and restrict the burning conditions until the flame goes out by itself. In this way, 30 it is possible to avoid greater damages and leave the sufficient time for the people to escape or to carry out firefighting and rescue operation in time. The present invention is a fireproofing cover based on aforesaid H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 - 5 demands. Within the panel in the building, the tail ends of the lighting fittings and the naked wire connections of electrical appliances are all laid inside the cover. On the bevel edge of the cover, the heat sinks are provided with 5 the air holes made on the fins. The air holes are through with the outside for air inflow so that the heat energy diffused by the electrical appliances in the operation can be discharged and the electrical appliances of the lighting fittings can operate normally. When the combustion occurs 10 inside the cover as to produce heat energy, the increasingly rising heat energy can only be discharged through the said air holes. As the heat sinks around the air holes are made of the expansion materials, which would go expanded once heated, the air holes on the heat sinks will be closed 15 automatically in an instant to prevent the external air from entering the fireproofing cover through the air holes. Thereby, the combustion area is controlled and the flame goes out by itself as there is no more inflowing air. 20 It can be seen from the operating principle of the fireproofing cover that the expansion performance of the intumescent material as used by the heat sinks is most important. The intumescent material of good performance can completely seal the air holes instantaneously and achieve 25 the goal of extinguishing fire automatically. The intumescent material of poor performance can't completely seal air holes as to affect the fireproof and extinguishing effect of the fireproofing cover. The known intumescent material used as the fireproofing sealing units is normally 30 made of a kind of intumescent matter, fiber framework and adhesive agent, and the intumescent matter is basically the flake graphite. H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 -6 The present invention has tried another kind of intumescent matter as the raw material, i.e. expandable graphite. The expandable graphite is known to have the following natures. 5 1. Generally, the grain size of graphite determines the expansion performance. It can be seen from Table 1 that the less the number of graphite mesh, the higher the expansibility. 2. For the same type of graphite, the different expansion 10 temperatures will bring about different expansibility. As shown in Figure 3, the higher the expansion temperature of graphite, the higher the expansibility. Table 1: Technical Specifications of Expandable graphite (Ordinary 15 Type) Type Carbon Volatility Water PH Grain Expansibility content content value % (times) 0 0 32-mesh Plus 200-400 s2.5 mesh (fine 280 80-99.9 s13 3-6 50-mesh quality 150-300 80-mesh 1) 100-200 100-mesh 100-130 Note: Methods to test expansion performance of graphite: Measure 50 ml of unexpanded graphite with a measuring cylinder and put it into the 1000 ml crucible. Increase temperature according to the designed 20 temperature rising procedures (at the temperature rising rate of OPH), and cool it down to the room temperature. Then measure the volume (ml) of the expanded graphite with the measuring cylinder. H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 - 7 The formula for calculating the expansibility of graphite: Expanse ibiity -- oIume(ml)after expansion-Volume(ml)beforeexpansion Volume(ml)beforeexpansion The present invention chooses the expandable graphite, 5 ceramic fiber and polyvinyl alcohol as the main raw materials to make the intumescent pieces. Through study and research, it has been found that: 1. The intumescent pieces made of the less mesh expandable 10 graphite have better expansion performance than those made of the more mesh expandable graphite. It can be seen from Table 2 that the intumescent pieces using the 32-mesh expandable graphite have much higher expansibility than those using the 80-mesh expandable graphite. 15 2. The higher the expansion temperature, the higher the expansibility of the intumescent pieces made of the expandable graphite (See Table 3). Table 2: Expansion Performance of Intumescent pieces Using the 20 Expandable graphite of Different Grains Mesh 32-mesh 80-mesh Volume before expansion 50 50 (ml) Volume after expansion (ml) 1500 800 Expansibility 30 times 16 times (Test conditions: The temperature rising rate OPH is set at 80% and the temperature is maintained at 1000 0 C for 2 minutes.) H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 - 8 Table 3: Expansion Performance of Intumescent Materials under Different Temperatures (taking 32-mesh expandable graphite as the raw material) Expansion temperature 600 800 1000 (OC) Volume before expansion 50 50 50 (ml) Volume after expansion 800 1200 1500 (ml) Expansibility 16 24 times 30 times times 5 Therefore, according to the actual need of the fireproofing cover, the present invention chooses 32-mesh expandable graphite as the raw material of special intumescent material used on the fireproofing cover. 10 Namely, the said intumescent material takes the ceramic fiber, 32-mesh expandable graphite and polyvinyl alcohol as its main raw materials. In the said intumescent material, the 32-mesh expandable 15 graphite has a content of 20-50%. The optimal preparation proportion of the said intumescent material is 60% of ceramic fiber, 25% of 32-mesh expandable graphite and 15% of polyvinyl alcohol. 20 The intumescent pieces on the heat sinks of the said fireproofing cover can use the ceramic fiber, 32-mesh expandable graphite and polyvinyl alcohol as the raw materials through the processing of stirring, lamination and drying. 25 H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 - 9 The advantageous effects of the present invention are as follows: 1. The fireproofing cover of the present invention can check the quick spreading of fire, causing the flame to 5 go out by itself as the combustion conditions are not available. 2. The special intumescent material for the heat sinks used on the fireproofing cover of the present invention has an excellent expansion performance, and it can 10 completely and instantly seal the air holes on the heat sinks of the fireproofing cover as to achieve the goal of extinguishing fire automatically. Description of the Drawings 15 Figure 1 is the structural schematic view showing the fireproofing cover of the present invention. Figure 2 is the schematic view of the fireproofing cover in the present invention, showing that it is mounted on the 20 lighting fitting. Figure 3 is the curve diagram showing that the expansibility of the graphite used in the present invention varies with the temperatures. 25 Figure 4 is the comparative curve showing that the intumescent piece in the present invention compares with that of the same kind abroad in respect of expansibility. 30 Description of the Particular Embodiments Below is a detailed description of the present invention in conjunction with the embodiments. H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 - 10 Embodiment A fireproofing cover is as shown in Fig. 1 and Fig. 2. It includes the cover top 1, bevel edge 2, cover enclosure 6 and cover skirt 9. On the bevel edge2, there are the heat 5 sinks comprising two layers: the expansion material plate underlayer 8 and the ceramic fiber paper upper layer 4. The heat sinks are installed on the bevel edge2 with rivets 13. On the heat sinks there are a number of air holes 3, one of them is a wire-passing hole 5. Inside the cover enclosure 6, 10 there is the inner cover support 14. The cover top 1, bevel edge 2, cover enclosure 6 and cover skirt 9 are made of the glass fiber cloth sewed together, the cloth is surfaced on one side with fireproofing painting coat able to resist the temperature as high as >750 0 C (it can be seen from the 15 figures that there is a sewing line 11 between the bevel edge 2 and cover enclosure 6), thus forming a closed cylinder. The two metal mounting supports 10 are fixed on both ends of the cover enclosure 6 through the rivets 13. The mounting supports 10 have mounting holes 7 and through 20 which the fireproofing cover can be mounted onto the ceiling panel 12 and hidden behind the ceiling panel 12. The electrical components at the back of the lighting fitting can thus be covered. The wires at the tail end of the lighting fittings go through the wire-passing hole 5. The 25 said intumescent piece 8 uses the ceramic fiber, 32-mesh expandable graphite and polyvinyl alcohol as the main raw materials. Preparation Example and Test Example 30 Prepare the intumescent piece as per the following methods: Put 60 kg of ceramic fiber and 25 kg of 32-mesh expandable graphite into 15 kg of polyvinyl alcohol, and prepare it H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 - 11 into 2# expansion material piece through the technological process of stirring, lamination and drying. Prepare the 1#, 3#, 44 and 5# intumescent material piece as 5 per the similar methods as above. Test the expansibility of 1#, 2#, 3#, 4# and 5# intumescent material pieces respectively under the different temperatures of 200-600 0 C. The results are shown in Table 4. 10 Table 4: Expansibility of Different Composition Intumescent Material Pieces under Different Temperatures (Times) 1# Ceramic fiber 65% 32-mesh expandable 1.5 3.5 5.5 7.5 9.5 graphite 20% Polyvinyl alcohol 15% 2# Ceramic fiber 65% 32-mesh expandable 2 4.5 7 9 11 graphite 25% Polyvinyl alcohol 15% 3# Ceramic fiber 55% 32-mesh expandable 2.5 5 7.5 10 12 graphite 30% Polyvinyl alcohol 15% 4# Ceramic fiber 45% 32-mesh expandable 3 6 9 12 14 graphite 40% Polyvinyl alcohol 15% 5# Ceramic fiber 35% 32-mesh expandable 3.5 7 11.5 14.5 17 graphite 50% Polyvinyl alcohol 15% H:\rosg\Keep\Other\P57249 - Fireproofing Cover and IntumeScent Material for Heat Sink.doc 20/06/05 - 12 l#, 2#, 3#, 4#, 5# intumescent material pieces have been respectively applied on the heat sinks of the fireproofing cover and the comparison test in respect to the sealing performances has been conducted, with the results obtained 5 as shown in Table 5. Table 5: Sealing Performance Comparison of Intumescent Material Pieces of Different Compositions l# 2# 3# 4# 5# Capable of Capable of Capable of Capable of Capable of sealing the sealing sealing sealing sealing air holes the air the air the air the air partially, holes holes holes holes but failure completely completely completely completely to seal the air holes completely 10 Brittleness comparison has been tested on the aforesaid l#, 2#, 3#, 4#, 5# intumescent material pieces, with the results obtained as shown in Table 6: Table 6: Comparison of Brittleness Performance of Intumescent 15 Material Pieces of Different Compositions 1# 2# 3# 4# 5# The finished Crease is Visible The finished The finished product is left when cracks are product is product soft and the finished found when broken when fails to be flexible, product is the finished folded folded by with a good folded, with product is together, 900, with a flexibility. a normal folded, with with a poor poor flexibility. a poor flexibility, flexibility. flexibility. H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent material for Heat Sink.doc 20/06/05 - 13 It can be seen from Table 4 that the higher the content of 32-mesh expandable graphite in the intumescent piece, the better the expansion performance. And it can also be seen from Table 5 and Table 6 that although the 2#, 3#, 4# and 5# 5 intumescent material pieces have a good expansion performance and can be used on the fireproof ing cover to satisfy the actual demands for quick expansion under high temperature and complete sealing of air holes on the heat sinks instantly, the higher content of 32-mesh expandable 10 graphite will cause the finished intumescent material piece to be easily hardened and get brittle crack, with the poorer flexibility. Therefore, 2# intumescent material piece, which has a content of 25% of the 32-mesh expandable graphite, is ultimately chosen as the optimal special intumescent 15 material piece for the heat sinks used on the fireproofing cover of the present invention. When the 2# intumescent material piece of the present invention is compared with the products of the same kind 20 abroad, the results obtained are as shown in Table 7 below: Table 7: Comparison of the Intumescent Material Piece of the Present Invention with the Products of the Same Kind Abroad Expansibility (times) Temperature 200 0 C 300 0 C 400 0 C 500 0 C 600 0 C Present invention 2 4.5 7 9 11 Abroad product 1.5 3 4 5 5.5 25 The aforesaid test results can also be reflected from Fig. 4. It can be seen from Table 6 and Fig. 4 that the special intumescent material piece for heat sinks used on the fireproofing cover is much better than the expansion performance of the same kind of products abroad. And the H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05 - 14 higher the temperature, the much better the expansion performance. It will be clearly understood that, although prior art use 5 and publications are referred to herein, this reference does not constitute an admission that any of these form a part of the common general knowledge in the art, in Australia or in any other country. 10 In the statement of invention and description of the invention which follow, except where the context requires otherwise due to express language or necessary implication, the word "comprise" or variations such as "comprises" or "comprising" is used in an inclusive sense, i.e. to specify 15 the presence of the stated features but not to preclude the presence or addition of further features in various embodiments of the invention. H:\rosg\Keep\Other\P57249 - Fireproofing Cover and Intumescent Material for Heat Sink.doc 20/06/05

Claims

1. A fireproofing cover comprising a cover body on which there are heat sinks with air holes, the heat sinks being 5 formed from two layers comprising an intumescent piece underlayer and a ceramic fiber paper upper layer.

2. The fireproofing cover as set forth in claim 1, wherein the cover body comprises a cover top, a bevel edge 10 fitted with the heat sinks with air holes, a cover enclosure and a cover skirt.

3. The fireproofing cover as set forth in claim 2, wherein fitted inside the said cover enclosure is an inner 15 cover support bracket.

4. The fireproofing cover as set forth in any one of claims 1, 2 or 3, wherein the cover body is made of glass fiber cloth, one side of the glass fiber cloth being 20 surfaced with a fireproofing paint coat having a heat resistance ability of >7500C.

5. The fireproofing cover as set forth in claim 2, wherein the cover enclosure is linked with a mounting 25 support, on which mounting support is provided mounting holes.

6. The fireproofing cover as set forth in claim 5, the said intumescent piece underlayer comprises 32-mesh 30 expandable graphite, ceramic fiber and polyvinyl alcohol. 3500$_1 (HMaUErs) P57249AU - 16

7. The fireproofing cover as set forth in claim 6, wherein the intumescent piece is made of 60% ceramic fiber, 25% 32-mesh expandable graphite and 15% polyvinyl alcohol through a process of stirring, lamination and 5 drying.

8. The fireproofing cover as set forth in claim 1, wherein the intumescent piece underlayer comprises 32-mesh expandable graphite, ceramic fiber and polyvinyl alcohol, 10 and the content of 32-mesh expandable graphite is 20%-0%.

9. The fireproofing cover as set forth in claim 8, wherein the intumescent piece underlayer is made of the ceramic fiber, 32-mesh expandable graphite and polyvinyl 15 alcohol through a process of stirring, lamination and drying.

10. The fireproofing cover as set forth in claim 8 or 9, wherein the intumescent piece underlayer comprises 60% 20 ceramic fibers, 25% 32-mesh expandable graphite, and 15% polyvinyl alcohol.

11. A fireproofing cover substantially as hereinbefore described with reference to accompanying drawings. f50O393_1 (GH-tatteis} Pe7249AU