A core regulating pad ring is padded on the lower ring of the thrust bearing, which can make the hook swing in any directions corresponding to the connecting cylinder.

在推力轴承下圈垫上调心垫圈，可使吊钩相对连接筒在任意方向上摆动。

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In the case of the Challenger, the culprit was a simple O-ring that had become too brittle to do its job after a freezing night waiting on the launch pad.

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