Image above: the focal point of the cottage is the cast-iron spiral staircase, which we commissioned.

上图：铸铁楼梯是整座别墅的焦点，是我们自己定制的。

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Through integral cast forming, the spiral torsional shaft has the advantages of high strength and abrasion resistance, safety and reliability, long service life, low using cost and the like.

本实用新型通过铸造一体成型，具有强度及耐磨性好、安全可靠、使用寿命长、使用成本低等特点。

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It had great views, but required a lot of climbing: it was spread over four levels up a long staircase from the elevator, with some floors connected only by a cast-iron spiral staircase.

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