球体必须包含一个能够排出到下游密封端口的反面的压力端口处。

And the ball must contain an adequate vent to the pressure port opposite of the downstream sealing port.

youdao

球体必须包含一个能够排出到下游密封端口的反面的压力端口处。

And the ball must contain an adequate vent to the pressure port opposite of the downstream sealing port.

youdao