The crimping die is made on a press, and our company has many such products. Our company makes stainless steel beer bottles, many of which are like this. I opened the molds and finished them. This mold is very simple, that is, turning. The lower die is positioned by the inner hole and turns a step circle. Make a U-shaped ring by numerical control on the upper die, which is the same size as the product. I hope I can help you!