| 摘要 |
A fire barrier comprises two outer layers 20, 30 of a fire resistant material, sandwiching a middle layer 10 of an intumescent material. The outer layers may comprise metal, glass fibre cloth, or cloth incorporating metal fibres. The middle layer may comprise graphite. Fastening means 50 hold the barrier together under normal conditions and may comprise polyethylene, polypropylene, or other material with a predetermined melting point. Stitching 40 also holds the barrier together and is slack under normal conditions. In response to a given temperature rise, fasteners 50 melt, or otherwise rupture, allowing expansion of middle layer 10. As layer 10 expands, stitching 40 becomes taut, restraining the expansion to a controlled thickness. Alternatively fasteners 40 do not rupture but undergo a controlled expansion. Such a fastener may be a shape memory spring which straightens out above a certain temperature. In this second embodiment the additional stitching 40 is not required. |
