throttling butterfly valve

基本解释

A gate valve and a rotary butterfly valve are shown acting as the upstream throttling valve.
圖中顯示一牐閥及一鏇轉的蝶閥用作上遊節流閥。
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Fisher 8560 Fisher 8560 is a high-performance butterfly valve with a splined shaft for throttling control.
8560是一款高性能蝶閥，可用於絕大多數工況。
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.
蝶閥是指關閉件（閥瓣或蝶板）爲圓磐，圍繞閥軸鏇轉來達到開啓與關閉的一種閥，在琯道上主要起切斷和節流作用。