Crane globe valves are highly efficient for services requiring frequent operation and throttling when pressure drop across the valve is about 20% of inlet pressure.

当通过阀门的压降为管路压力的20%左右时，美国克雷恩截止阀就能够高效应用在频繁操作和节流的应用场合。

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Engine pressure ratio (EPR), the ratio of inlet pressure over exhaust-let pressure measurements. The ratio is used as the primary parameter to set thrust on some engines.

发动机压力比(epr)，进气压力与排气压力值的比，某些发动机以此作为设定推力的主要依据。

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The pressure in rocket tanks and the pressure on the inlet of main pumps can be increased by using boost pumps, so as to ensure that the main pumps can work reliably without cavitation erosion.

使用辅助增压泵可降低贮箱压力，并提高发动机主泵的入口压力，以保证主泵在没有汽蚀的条件下可靠工作；

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