vent valve

基本解释

As fluid is evacuated from the system or vessel, the vent valve must open to prevent formation of a vacuum.
当流体从系统或容器中排空时，排放阀必须打开以防止出现真空现象。
The vent valve comprises an air vent screw, a spring and a valve ball which leans against the channel under the acting force of the spring.
所述排气阀包括一排气螺钉、一弹簧、一钢球，阀球在弹簧作用力下抵靠通道上。
ip.com
The calculation formulas for drain valve and vent valve in long drainpipe are approached, and the valve diameters are calculated being compared with the result in some literature.
探讨了热水管网放水阀、放气阀直径的计算公式，计算了长放水管放水阀直径，并与文献中短放水管放水阀直径进行了比较。

The airline said an open valve caused one tank to overflow through a vent.
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These valves use a screw type valve instead of a simple flap, and they have a pressure regulating mechanism that will vent water to the ground if the intake pressure exceeds a set level.
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