摘要 |
A device for shutting-off a plastics pipe in the event of a fire comprises a sheath of a flexible refractory fabric around a portion of the pipe within or adjacent a fire-resisting partition such as a wall or floor. A spring is placed under tension around the fabric and acts to radially constrict the pipe and sheath, when the pipe softens in the event of a fire. Upon subsequent burning, the burnt plastics forms a foam-like carbon mass which plugs the constricted sheath.
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