Police say the saboteur must have had a working familiarity with the refinery to be able to open the tank's main valve and send tons of oil pouring out.
警方表示，嫌疑犯熟悉油厂事务，而且能打开阀门，让好几百万吨的石油哗啦啦的流走。
2
The top steam discharge valve discharge distance could regulate to maintain the working pressure.
顶部排汽阀的开度应调控，以保持连排内的工作压力。
3
Substantial construction, working principle and practical maintenance method of revolving valve type power steering gear is presented in detail.