| 摘要 |
<p>Heat collector's spiralling water pipe is made of plastic and its transparent cover of polyester reinforced with glass fibre. The water pipe is pref. blackened, and the plastic used is pref. polypropylene, polybutene, a polycarbonate or an elastomer. The collector's housing is pref. of wood, lined with Al foil and with a profiled Al strip to protect the outside edges and to hold the transparent cover in place.</p> |
