Crack in neck of hollow shaft is a very serious malfunction, main cause of the crack include: foundry defect, centralized stress, quality problems of welding and heat treatment.

中空轴轴颈裂纹是水泥磨的严重故障。中空轴轴颈裂纹产生的原因主要有：铸造缺陷，应力集中，焊接和热处理质量问题等。

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Plating into a transition (radius transition or undercut) will create a stress concentration that can cause crack initiation.

如果过渡段被电镀(倒角和内切槽)将会产生应力集中，造成裂纹。

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T his paper analysis and discuss the cause of crack, and put forward the way of treatment which could be a reference for the design and construction on anchorage block of penstock.

从多方面分析、论述裂缝产生的原因，详细阐述处理措施，对进一步完善压力钢管镇墩的设计以及制定其施工方案提供参考。

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The Federal Highway Administration concluded that the main cause was a crack that grew undetected in one of the bridge's huge chain links, but that the high volume of traffic was also a factor.

NPR: Bumper to Bumper: Predicting Traffic Flow