vacuum degassing短语¹⁴⁴⁹⁷²⁺² 基本例句 真空除气 The comparative of characteristic, investment and production cost between VD and RH was introduced. A proposal of vacuum degassing equipment suitable for BOF shop or EAF shop was put for ward. 在介绍 VD和 RH真空处理的特点、投资和生产成本的前提下，提出电炉和转炉炼钢配置真空处理装置时的选用原则。 chemyq