when the port is in line with both ends of the valve, flow will occur gen.

[Whiteberry]

Всем привет! Есть такой контекст. Подкажите пож-та как лучше перевести "when the port is in line with both ends of the valve, flow will occur" и "ever will be inline with the port position"

Ball valve is a rotational motion valve that uses a ball-shaped disk to stop or start fluid flow. Moving element, the ball, has a hole, or port, through the middle so that through the middle so that when the port is in line with both ends of the valve, flow will occur. When the valve is closed, the hole is perpendicular to the ends of the valve, and flow is blocked. The handle or lever will be inline with the port position letting you "see" the valve's position. The ball valve, along with the butterfly valve and plug valve, are part of the family of quarter turn valves.

когда отверстие и концы крана находятся на одной линии??? как вот...выразить мысль...

Заранее спасибо!

[Enote]

когда порт соосен с концами крана, пропуск. способность макс.
повторяет положение (оси) порта