The mold used for stretching is called a stretching mold, which is a tool for mass processing materials (metal or non-metal) into required stampings. Stretching molds can be categorized into single-stroke deep drawing molds, compound molds, and progressive deep drawing molds based on their assembly. They can also be distinguished by the stamping press used, such as single-action press stretching molds, double-action press stretching molds, and triple-action press stretching molds, with the main differentiating factor being the type of edge holding device (elastic or rigid). Stretching molds can also be divided into initial deep drawing molds and subsequent process deep drawing molds, with the main difference lying in the structure and positioning of the edge holding rings.