Working state of a screw pump rod-line is analyzed using Finite element analysis method during broken working station, and three kinds of possible mechanical models are set up.
如何降低螺杆泵抽油杆的应力水平，提高工作寿命是石油开采设备研究中一个急需解决的力学问题。
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Next to it a boy leaned against the railings, his rod and line dangling out over the floating garbage and the stream of brown, stinking waste which trickled from a pipe in the wall below.
At one point, one man, not Inupiat, posed beside the whale holding a small fishing rod, pretending for a camera that he had caught it on eight-pound line.