| 摘要 |
<p>Ring sectors (8), made of material which foams under heat, make up a sleeve (4) for plastics pipes, providing protection from fire, while being robust, compact for transport and storage, and easily and cheaply made. The ring sectors are lockable, and made from densely pressed granular material. They can have peripheral sealing, can be embedded in backing sheet metal plates (9), and interconnected by flexible intermediate pieces, and enclosed in a shared foil sheet. In shaping the sectors, granular material is pressed out into a series of such sectors.</p> |
