Mold design and manufacturing, the designer’s experience and skills play a key role. Designed or not, be confirmed by the test mode; and mold tryout is required by many and repeated changes to the final completion. Production practice, some die soon after put into production line use, but often have a variety of problems, unable to meet production requirements or technical requirements, resulting in production of non-normal shutdown, etc., brought many unstable factors. So, how to improve the stability of the stamping mold, mold manufacturing enterprises are facing a real problem.
The stability of stamping mold and influencing factors
What is stability? Stability can be divided into the production process stability and reliability. Process stability refers to the production of qualified products to meet the stability of the process plan; production stability refers to the stability of the production process has a production capacity.
Due to domestic manufacturing enterprises of stamping mold are mostly small and medium enterprises, and a considerable portion of which, still remain in the traditional workshop-style production management phase, the stability of the mold is often overlooked, resulting in mold development cycle is long, the problem of higher manufacturing costs, serious hampered the pace of development.
Let us look at the the main factors that impact the stability of stamping mold, namely: use of the mold material; mold structure of the strength requirements; stamping material properties of stability; material thickness of the wave characteristics; range of materials ; tensile resistance of reinforcement size; BHF range; lubricant selection.
A weighted combination of the factors affecting the stability
It is noteworthy that, in the stamping process, because each has its own sheet metal stamping chemical composition, mechanical properties and performance are closely related with the characteristics of stamping the value of the material properties of unstable stamping, stamping material thickness fluctuations, and stamping material changes, not only directly affect the processing of precision metal forming and quality, may also lead to mold damage.
To stretch tendons, for example, it will occupy in the stamping in a very important position. In the stretch forming process, the products need to have a certain size, shape and distribution along the fixed around the appropriate tension, the tension force from the stamping device, the edge of the material deformation resistance and the flow of the blank holder surface resistance. The flow resistance generation, if only to rely on the role of blank holder force, the friction between the mold and the material is not enough.
To this end, must also be set on the blank holder can have a greater resistance to stretch tendons to increase the resistance of the feed, so that the materials have a greater plastic deformation, in order to meet the material plastic deformation and plastic flow requirements. Meanwhile, the resistance by changing the size of muscle stretching and distribution, and control the flow of material to mold the speed and fluxes, to achieve the various parts of the tensile deformation of tension within the region and the distribution of effective regulation to prevent stretching forming the product of the breakdown, wrinkling, and distortion and other quality problems. Clear from the stamping process and die in the development of the design process, we must consider the size of tensile resistance, according to BHF range of variation to determine the layout of tensile bars and tensile reinforcement in the form, so that the deformation of the deformation zone as requireddeformation mode and complete the shape.