下列属于防爆泄压装置的有()。
A、安全阀
B、单向阀
C、爆破片
D、防爆门
参考答案:A, C, D
The actress is already 50, but she looks than she really is.
A.young
B.more young
C.more younger
D.much younger
会引起离心泵振动的是()。
A.转子不平衡
B.外部件附属管线振动
C.轴承过度摩擦
D.轴承孔间隙小