drain valve短语¹¹⁴⁴⁶⁷⁺⁴ 基本例句 排水阀,泄水阀 The drain valve is opened or closed by taking advantage of the change of liquid level of condensate water with the high- precision grinding stainless steel hollow float ball in the valve cavity. 利用高精度研磨不锈钢空心浮球在阀腔内随着凝结水的液位变化开启或关闭阀门。 ywbb