当钻头横刃过长时()。
A、孔的位置易偏移和歪斜
B、轴向力小
C、钻头耐用度好
D、钻孔平稳
参考答案:A
What is the most appropriate title for this passage a. Two Types of Stocks b. A New Strategy of Investment c. Distinctions between Trading and Investment d. Conflicting Perspectives on Stock Investment
当介质温度在0℃~80℃时,应由泵出口或高压端将输送的干净介质直接引入(),冷却密封端面。
A、导流室
B、叶轮流道
C、密封腔
D、扩散室