常見例句雙語例句Open the valve on the vent line just upstream the trip valve.打開速閉閥上游放空管線上的閥門。This digitalized optical fiber transmission system is upstream line of the bi-directional optical fiber transmission system.數(shù)字化光纖傳輸系統(tǒng)，為有線制導(dǎo)光纖傳輸系統(tǒng)的一個(gè)部分；Butterfly or similar type valves should be installed in the line upstream and downstream of the automatic control valve to allow for maintenance service.在自動(dòng)控制閥的上游和下游應(yīng)該安裝蝶閥或類似的閥門，以便于進(jìn)行維護(hù)維修。 返回 upstream line