本论文写的是臂架型的。

This paper is about the type boom.

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臂架型起重机：可在圆形场地及其上空作业，多用于露天装卸及安装等工作。

Jib crane: in circles over the operation site and more for open-air handling and installation work.

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为解决第3代206kp型转向架定位臂在运用中的疲劳破坏问题，提出了2种改进方案。

Two improvement schemes are put forward to solve the problem of fatigue damage in operation of the positioning arms for the 3 ~ (rd) generation 206kp bogies.

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