open and shut valve

基本解釋

Heart sounds is heart throb process in , shut by the valve inside the heart , open , and the sound that the oscillatory place such as systole or diastole produces.
心音是心臟搏動過程中，由心臟內(nèi)瓣膜關(guān)閉、開放、以及收縮或舒張等振動所產(chǎn)生的聲音。
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Many pressure dominated testing valve is through pumping of relieving annulus pressure to realize open or shut down hole test valve and keep annulus pressure for certain all the time.
許多種壓控測試閥均是通過環(huán)空加泵壓打開，泄掉泵壓關(guān)閉，開井過程中環(huán)空始終保持一定的開啟壓力。
Butterfly valve is closed parts ( valve flap or disc for disc ), around the valve axis of rotation to achieve the open and close a valve, in the pipeline mainly as shut off and throttling effect.
蝶閥是指關(guān)閉件（閥瓣或蝶板）為圓盤，圍繞閥軸旋轉(zhuǎn)來達(dá)到開啟與關(guān)閉的一種閥，在管道上主要起切斷和節(jié)流作用。