| 摘要 |
<p>The total outlet cross-secti-nal area of the tuyeres of a cupola is equal to 0.02-0.18 of the cross-sectional area of the shaft in the plane of location of the tuyeres. Pref. the outlet cross-sectional area of each tuyere is such that the distances from the tuyere lower edge to the hearth and from the tuyere upper edge to the top of the refractory bed in the cupola are, respectively, 0.8d-7.0d and 2d-16d (where d is the dia. of a circle whose area is equal to the cross-sectional area of the tuyere outlet). The cupola is a natural gas-fired cupola used e.g. for melting cast iron or producing slag and mineral wool. The design gves uniform gas distribution among the tuyeres and in the refractory bed, stabilisation of the combustion process, prodn. of a high temp. at the top of the refractory bed and at the hearth, durability of the refractory bed and avoidance of melt freezing on the hearth.</p> |
