n.用以遮閉之物；栓；遮斷

No downstream shutoff valves are allowed. 不允許有下游關(guān)閉閥。

FLIGHT CONTROLS HYDRAULIC SHUTOFF VALVES. 飛行操縱液壓關(guān)斷活門。

Close the shutoff valve upstream of the regulator. 關(guān)閉調(diào)節(jié)閥上游的關(guān)斷閥。

Start Up: The downstream shutoff should be closed. 啟動(dòng)：下游關(guān)閉閥應(yīng)該處于關(guān)閉狀態(tài)。

Purpose: To test shutoff #2 for tightness. 目的：檢測(cè)關(guān)閉2號(hào)的緊固密封性。