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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Bruising a grey or mottled effect, most noticeable in coated papers. It is a paper defect caused by undue heat or pressure in the calendars.

在粉纸上特别显著的灰色或斑点状情况。这是砑光机上的过度热力或压力所造成的纸张故障。

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The heat rollers can become torn or warped after a period of time causing an image defect.

热辊可以成为撕裂或扭曲后，在一段时间内造成的图像缺陷。

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The sportswear company has issued a recall for seven Omni-Heat electric jacket models, citing a manufacturing defect in the heated inner wrist cuff.

ENGADGET: Columbia recalls Omni-Heat electric jackets due to burn hazard (or, for working too well)