Chamfering forming process for double-end bolt middle hexagonal flange and die structure

The invention discloses a chamfering forming process for a double-end bolt middle hexagonal flange and a die structure. The chamfering forming process comprises the steps: shearing a blank, carrying out two-end rod bundling, and carrying out middle upsetting; carrying out hexagon premolding, and constructing inverted-cone-shaped appearance; patting a frustum to be flat, filling the hexagon with amaterial, and forming an upper chamfer and a bundle tail; and leveling a hexagon washer, and forming a chamfer on another surface at the same time. A cold upsetting forming scheme is adopted in the whole process, waste of raw materials is reduced, procedures are saved, the production cost is reduced, and meanwhile, the performance and quality of products are improved. 一种双头螺栓中间六角法兰倒角成形工艺及模具结构，包括剪切胚料、两头束杆，中间镦粗；预成型六角，倒锥形造势；将锥台拍平，让材料填充满六角，成型上面倒角和束尾；整平六角华司，同时成型另一面倒角。整个过程采用冷镦成型方案，减少原材料的浪费，节约工序，降低了生产成本，同时提高了产品的性能及质量。