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Cold heading: According to the theory of metal plastic deformation, a certain pressure is applied to the metal blank at room temperature to cause plastic deformation in the mold cavity, and it is formed according to the specified shape and size. The pier is mainly used for mass production of fasteners such as nuts, bolts, etc. It has good surface quality, high dimensional accuracy, high efficiency and stable product quality.

For the upsetting of small precision parts, the mass production of non-standard screws for fasteners, etc., with high efficiency and obvious cost advantages