throttling butterfly valve

基本解释

A gate valve and a rotary butterfly valve are shown acting as the upstream throttling valve.
图中显示一闸阀及一旋转的蝶阀用作上游节流阀。
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Fisher 8560 Fisher 8560 is a high-performance butterfly valve with a splined shaft for throttling control.
8560是一款高性能蝶阀，可用于绝大多数工况。
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.
蝶阀是指关闭件（阀瓣或蝶板）为圆盘，围绕阀轴旋转来达到开启与关闭的一种阀，在管道上主要起切断和节流作用。