Helicoid spiral form of entity (S method) and the spiral belt (D method) two.

螺旋面的形式有实体螺旋（S制法）和带式螺旋（D制法）两种。

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According the laevorotatory helicoid structure characteristic of the stainless steel spiral plate, analyzed the forming process, and introduced forming die structure.

针对不锈钢螺旋板的左旋螺旋面结构特点，分析了成形工艺，并介绍了成形模具结构。

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