Having been deeply involved in the mold industry for many years, we have some experience to share with you in the design and forming of automotive stamping molds.
1. Before designing a strip, it is essential to understand the part's tolerance requirements, material properties, press tonnage, press table dimensions, SPM (strokes per minute), feed direction, feed height, tooling requirements, material utilization, and tooling life.
2. When designing the strip, CAE analysis should be carried out simultaneously, primarily considering the material's thinning rate, which is generally below 20% (though requirements may vary among customers). It is crucial to communicate frequently with the customer. The empty step is also very important; if the mold length allows, leaving an appropriate empty step for the test mold after a mold change can be very helpful.
3. Strip design involves analyzing the product molding process, which fundamentally determines the success of the mold.
4. In continuous mold design, the lifting material design is crucial. If the lifting bar cannot lift the entire material belt, it may swing excessively during the feeding process, preventing an increase in SPM and hindering automated continuous production.
5. In mold design, the choice of mold material, heat treatment, and surface treatment (e.g., TD, TICN, which requires 3-4 days) is crucial, especially for drawn parts. Without TD, the surface of the mold will easily be drawn and burnt.
6. In mould design, for holes or tolerance requirements of smaller surfaces, it is advisable to use adjustable inserts where possible. These are easy to adjust during trial molding and production, allowing for easier achievement of required part sizes. When making adjustable inserts for both the upper and lower molds, ensure that the insertion direction is consistent and parallel to a specific edge of the product. For the word mark, if the press requirements can be removed, there is no need to dismantle the mould again, which saves time.
7. When designing a hydrogen spring, base it on the pressure analyzed by CAE. Avoid designing a spring that is too large, as this could cause the product to rupture. Usually, the situation is as follows: when pressure is low, the product wrinkles; when pressure is high, the product ruptures. To solve product wrinkling, you can locally increase the stretching bar. First, use the stretching bar to fix the sheet, then stretch it to reduce wrinkles. If there is a gas top bar on the punch press, use it to adjust the pressing force.
8. When trying the mold for the first time, slowly close the upper mold. For the stretching process, use the fuse to test the material thickness level and the gap between materials. Then try the mold, ensuring the knife edge is good first. Please use movable inserts to adjust the height of the stretching bar.
9. During the mold test, ensure that the datum holes and surfaces match with the molds before placing the products on the checker for measurement or sending them to CMM for a 3D report. Otherwise, the test is meaningless.
10. For 3D complex products, you can use the 3D laser method. Before 3D laser scanning, 3D graphics must be prepared. Use CNC to establish a good datum position before sending the product for 3D laser scanning. The 3D laser process also includes positioning and sanding.
Post time: Jul-16-2024