The function of the valve is to release any excess pressure from the system caused by thermal expansion of the water.

这种阀门的作用在于释放由于水的热膨胀导致的过大的压力。

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A pressure relief valve must be installed as shown to prevent excess pressure by thermal expansion.

必须按照图示安装压力安全阀，以防止由于热膨胀产生的过高压力。

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Installed on a by-pass line, mainline pressure is accurately controlled by relief of excess pressure.

安装一条旁路管线，通过释放过大的压力实现主管线压力的精确控制。

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This is particularly needed to avoid having excess pressure cause problems when you are receiving a relay from another engine.

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This can be just the result of the excess pressure placed on the nerve or it can also be caused by neck or back trauma, a herniated disk in the spine, or a mass (such as a tumor or infection).

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It is the phantom shares that allegedly put excess downward pressure on a stock.

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