Stretch mold is a type of mold used to process stretch formed components. It is an indispensable tool for manufacturing various metal parts. It is suitable for various fields, such as automobiles, machine manufacturing, household appliances, construction, etc. Stretch molds are an important industrial production equipment, and their manufacturing materials and quality directly affect the processing quality and production efficiency of products. In this article, we will explore the manufacturing materials for stretching molds.

The mold used for stretching is called a stretching die, which is a specialized tool for batch processing materials (metal or non-metal) into the required stamping parts. If the types of drawing dies are distinguished by combination, they can be divided into single process drawing dies, composite dies, and progressive drawing dies. Distinguished by stamping equipment, it can also be divided into drawing dies for single action presses, drawing dies for double action presses, and drawing dies for triple action presses

There are many types of products in the mold industry, among which the drawing die belongs to a type with higher technical content. Due to the following difficulties, it is difficult to stretch the mold: 1. Design and calculation; 2. Mold testing after mold design is completed. For designers, to design a reasonable stretching mold structure, they need to accumulate rich design experience.

Stamping conditions of the stretching die: Excessive blank holding force. When the edge pressing force is too large, wrinkling will not occur on the flange surface. The roughness of the anti wrinkle pressure plate surface, mold fit, gap, rp, rd, type and coating conditions of processing oil, and the distribution of the edge holding force caused by the buffer pin all affect the anti wrinkle pressure. If all of the above conditions for deep drawing are appropriate, the blank holder force will decrease and rupture will not occur before wrinkling. When the edge pressing force is too large, it is easy to determine because the flange surface will be fully illuminated.

Cracks at corresponding parts of punch shoulder: due to insufficient strength of the material, this defect will occur when the drawing load reaches the material breaking load. The defect occurs at the corresponding part (rp) of the shoulder R of the punch, which is closer to rp than the impact mark line. The impact mark line of the ruptured part can be observed and checked for the following situations, as it is different from other parts: or it can be extended; Or there are shiny parts above and below the flange; Or wrinkles may occur. In addition, there are sometimes shiny parts on the side walls. Initially, it ruptured laterally and presented as a tongue like shape.