1、Two-high mill is a kind of major equipment for merchant bar production.
二輥軋機是中小型軋鋼生產中一種主要的軋制設備。

2、Major equipment and critical utilities and systems, however, require IQ, OQ and PQ.
對主要的設備、關鍵的公用設施和系統，還需要開展IQ、OQ和PQ。

3、Electric furnace is major equipment of zinc powder reduction smelting.
電爐是鋅粉工藝進行還原熔煉的承載設備。

major equipment翻譯