短語詞組短語back draught oxygen lance 倒錐度氧槍back draught stack 倒流休風(fēng)煙囪back draught system 倒流休風(fēng)系統(tǒng)back draught efficency 反風(fēng)率back draught four -segment type mandrel 四棱錐卷筒draught back 倒流休風(fēng) 返回 backdraught