Question

请帮我翻译下面几句话到英语，谢谢

1如果不在启动前灌泵的话，那么输送的会是空气，从而造成压差或泵吸入口的真空度过小，使得液体无法被吸入泵内。

2当增大流量调节阀的开度时，压力表上的数据会变小，真空表上的数据则会变大。

3离心泵应该按照所输送的液体进行选择，并且也要参考需要的性能，分析抽吸，排出条件，是间歇运行还是连续运行等。还要计算泵的轴功率。

Answer 1

1. If the pump is not filled with fluid before start up, then the air would be delivered, resulted in too low pressure differential or vacuum at the pump entry, so the liquid could not be sucted into the pump.
2 When increasing the opening of flow control valve, the reading on pressure indicator will drop, while on vacuum indicator, increases.
3. The pump selection should be based on the fluid delivered. The performance needed, suction and discharge conditions, continuous or intermittent running, etc should be taen into consideration. And also, the shaft horsepower of the pump should be calculated.