How to Make Stamping Die

In the field of mechanical processing, Stamping forming is the most common method. It can not only process metal and non-metallic materials, but also process some mechanical parts, electronic products, and transportation tools, such as pressure vessel heads, inner and outer covers, precision parts such as instruments. Nowadays, with the continuous development and progress of science and technology, Stamping forming technology, as the foundation of the development of various industries, also faces enormous challenges. In order to adapt to market development, only faster, more accurate and efficient production of stamping molds can achieve sustainable development of enterprises.

Ⅰ.Overview of stamping forming process

(1) The Concept and Characteristics of Stamping Forming

The so-called stamping forming refers to a processing and forming process where different types of presses and corresponding stamping molds are used to apply external pressure to sheet, strip, tube, and other materials until they undergo plastic deformation or separation, in order to obtain the desired shape and performance of the workpiece. The components formed by stamping are relatively light in weight, thin in thickness, and have high structural rigidity, strength, and quality stability. They can be put into use without the need for secondary mechanical cutting. The characteristics of stamping molds are mainly reflected in the following aspects: ① the material utilization rate can reach around 90%~95%; ② The advantages are more significant in the processing of thin-walled and complex shaped parts; ③ The shape and size of stamped components demonstrate excellent interchangeability; ④ The equipment is relatively easy to operate, has a high degree of automation, and has a low scrap rate.

(2) Composition of stamping mold parts

1. Supporting parts. In stamping molds, the supporting parts mainly include upper and lower mold seats; Convex and concave mold fixing plates; The existence of supporting components such as mold handles and limit support plates is mainly to provide guarantee for the connection performance of various components of the stamping mold. These parts are generally made of low-carbon steel or ductile iron, with moderate hardness and very simple shapes. They are generally manufactured using high-speed milling. 2. Working parts. In the process of stamping dies, the convex and concave molds are the most important part, mainly covering alloy steel with high hardness. The working parts are mainly installed in the press and used repeatedly to complete the processing of stamping formed parts. Due to the high hardness and complex shape of the working parts themselves, they are often manufactured using machining methods such as electric discharge and wire cutting. 3. Guide parts. The guide parts in stamping molds include related equipment such as guide sleeves, guide pillars, and guide barrels. The precision requirements of the guide parts are relatively high, and in addition, the production batch is relatively large, making it more suitable for use in the working range with a longer lifespan of the mold. Guiding parts are generally manufactured using high-quality low-carbon steel and processed through high-precision CNC lathes. 4. Position the parts. The positioning parts include related equipment such as guide pins, guide plates, retaining pins, positioning pins, etc. They generally determine the stamping positions of stamping mold components and blank parts to avoid displacement caused by the impact pressure on the supporting components; At the same time, positioning parts can also be applied to determine the accuracy of the stamping die blade position for blank materials, in order to ensure the qualification of the processed products.

II. CNC machining process for stamping mold parts

(1) Analyze stamping mold part drawings

Analyzing the drawings of stamping die parts and determining dimensional accuracy and process requirements is the primary prerequisite for developing a CNC machining process usage plan, which mainly includes labeling the dimensions of the machining parts and analyzing the geometric elements of the part contour. 1. Mark the dimensions of the machining parts. Dimensional annotation of stamping die parts drawings needs to be combined with the characteristics of CNC machining, and must comply with the specific requirements proposed by CNC programming and machining to ensure uniform standards. Generally, the dimensioning of parts needs to be unified for the development of CNC machining programs, part design standards, machining process standards, and inspection and measurement standards. If there is a lack of dimensioning design standards in the drawing of stamping die parts, the machining personnel can reasonably determine the machining standards on the basis of ensuring that it does not affect the accuracy of stamping die parts. 2. Analysis of geometric elements of part contour. When exploring the CNC machining process of stamping die parts, it is necessary to redefine the geometric elements of all parts to meet the relevant requirements of CNC programming. Such as component composition elements, contour export elements, etc.

(2) Determine the processing sequence of stamping mold parts

1. Improve machining accuracy. After determining the actual machining position and content of stamping die parts, it is necessary to start analyzing the direct and indirect dimensional accuracy connections of each part of the part, in order to avoid the impact of the size of the parts that have already been processed on the dimensional accuracy of the parts that have not been processed; If cutting deformation and cutting force have a significant impact on dimensional accuracy, it is important to focus on the processing sequence. 2. Improve productivity. In the process of machining stamping mold parts through CNC machining, it is necessary to arrange the specific sequence and steps of CNC machining, use appropriate machining tools, and observe the actual running trajectory of CNC machining tools, in order to effectively reduce the number of tool changes during machining and achieve an increase in labor productivity.

(3) Clarify the reasonable usage of parts for cutting and processing

1. Rough machining of the contour. For rough machining of stamping die parts, it is necessary to remove the machining amount of the inner and outer contour surfaces of the workpiece, which is also the most important task of rough machining. Therefore, when determining the cutting amount, it is necessary to select the maximum back feed and the fastest feed speed based on the performance requirements of the cutting tool and CNC machine tool [3]; In addition, consideration should also be given to the distance between tool changes and the actual position of tool retraction during machining, in order to shorten the idle stroke of the machining tool. 2. Profile precision machining. For precision machining of stamping die parts, it is necessary to clarify the dimensions, positional accuracy, and surface quality of the processed parts. At this point, the requirements for tool performance and cutting amount are relatively high. On the basis of ensuring tool wear resistance, it is necessary to use a medium cutting speed tool to reduce workpiece vibration; Control the surface quality of the parts using a relatively small amount of back cutting force; Use a reasonable feed rate to avoid chips and unnecessary scratches. （4） For stamping mold parts with complex shapes, automatic programming is necessary for processing personnel to complete the processing through automatic programming methods. Before officially entering automatic programming, machining personnel need to establish a contour model for stamping die parts, and then represent the geometric elements and features of the processed parts. Based on this, they need to determine the coordinates of the processed workpiece, tool geometry, and cutting parameters of the tool, and then choose appropriate machining methods.

III.Conclusion

In summary, the CNC machining process of stamping die parts is of great significance in the field of part processing. It can develop a reasonable CNC machining process plan, improve the efficiency of stamping die processing, and thus promote the rapid development of the industrial industry.