交联管加热段的鼓风机主要作用是在正常生产过程中,保持加热段温度均匀。
参考答案:错
How is the annual rate of change for magnetic variation shown on a pilot chart?()
A.Gray lines on the uppermost inset chart
B.Red lines on the main body of the chart
C.In parenthesis on the lines of equal magnetic variation
D.Annual rate of change is not shown
液化气罐安全阀开启压力为储罐的(),规定()检验一次,检验定压后要加(),在运行发生起跳或不严应及时处理。