| 摘要 |
<p>The furnace casing has a horizontal cross-section which is polygonal, with 2n sides, where n is a whole number. One of each pair of sides carries electric resistance heater elements, the parts of the elements inside the furnace casing being parallel with the sides of the polygon. The pref. horizontal cross-section is a regular, and each heater element is pref. a sintered SiC rod with a U-shape. The legs of each U-element are pref. horizontal, but the legs of any one element are pref. in different horizontal planes. The overall result is that workers can stand near the furnace casing when filling a hand ladle.</p> |
