When size of choke line is not variable, the first and second circulation rate increases with welldepth increasing.
对于某一特定尺寸的节流管线，第一循环周及第二循环周的最大流量随着水深的增加而增加；
2
For the abundant of noise in testing oil welldepth with sound wave, it is difficult to locate the reflected sound wave.
在用声波测试油井油液面深时，反射声波受到大量杂波干扰，给接箍波和液面波的定位带来了极大的困难。
3
During developing welldepth measurement system for mud logging unit, it directly affects the accuracy of welldepth measurement whether winch sensor signal processing is rational or not.