Typical structure and manufacturing technology of stamping die
Typical structure
First category
Process parts, such parts directly participate in the completion of the process and have direct contact with the blank, including working parts, positioning parts, discharge and press parts, etc .;
Second category
Structural parts. Such parts do not directly participate in the completion of the process, nor do they have direct contact with the blank. They only guarantee the completion of the process of the mold or improve the function of the mold. Other parts are shown in Table 1.1.3. It should be pointed out that not all the dies must have the above six parts, especially single-process dies, but working parts and necessary fixed parts are indispensable.
Manufacturing Technology
The modernization of mold manufacturing technology is the basis for the development of the mold industry. With the development of science and technology, advanced technologies such as computer technology, information technology, and automation technology are constantly infiltrating, intersecting, and integrating into traditional manufacturing technologies, and transforming them to form advanced manufacturing technologies. The new in-die tapping technology has led many stamping manufacturers to reduce the cost and caused a rush of buying.
The development of advanced mold manufacturing technology is mainly reflected in:
High-speed milling
Ordinary milling uses a low feed rate and large cutting parameters, while high-speed milling uses a high feed rate and small cutting parameters. Compared with ordinary milling, high-speed milling has the following characteristics:
a. High-efficiency The spindle speed of high-speed milling is generally 15000r / min ~ 40000r / min, up to 100,000r / min. When cutting steel, its cutting speed is about 400m / min, which is 5-10 times higher than that of traditional milling processing; compared with traditional processing methods (traditional milling, EDM processing, etc.) when processing mold cavities, its efficiency Increase 4 ~ 5 times.
b. High-precision High-speed milling processing accuracy is generally 10 μm, and some accuracy is even higher.
c. High surface quality Due to the small temperature rise of the workpiece during high-speed milling (approximately 3 ° C), there is no deterioration layer and micro-cracks on the surface, and thermal deformation is small. The best surface roughness Ra is less than 1 μm, which reduces the subsequent grinding and polishing workload.
d. Machinable high-hard materials. Milling of steel with 50 ~ 54HRC, the highest hardness of milling can reach 6HRC.
In view of the above-mentioned advantages of high-speed machining, high-speed machining is being widely used in mold manufacturing, and gradually replaces some grinding and electrical machining.
EDM milling
EDM milling (also known as EDM creation) is a major development of EDM technology, which is a new technology that replaces the traditional mold electrode processing of mold cavities. Like NC milling, EDM milling uses high-speed rotating rod-shaped electrodes to process two-dimensional or three-dimensional contours of the workpiece without the need to manufacture complex and expensive formed electrodes. Japan's Mitsubishi EDSCAN8E EDM machine tool is equipped with automatic electrode loss compensation system, CAD / CAM integrated system, online automatic measurement system and dynamic simulation system, which reflects the current level of EDM machine tools.
Slow walking wire cutting technology
The development level of CNC slow-feed wire cutting technology has been quite high, the functions are quite complete, and the degree of automation has reached the level of unattended operation. The maximum cutting speed has reached 300mm2 / min, the machining accuracy can reach ± 1.5μm, and the surface roughness Ra0.1 ~ 0.2μm. The development of wire cutting technology with a diameter of 0.03 ~ 0.1mm can realize the one-time cutting of the concave-convex die, and can perform the cutting process of the narrow groove of 0.04mm and the inner radius of 0.02mm. Taper cutting technology has been able to perform precision machining of taper above 30 °.
Grinding and polishing technology Grinding and polishing processing is widely used in precision mold processing due to its high accuracy, good surface quality, and low surface roughness. Precision mold manufacturing widely uses advanced equipment and technologies such as CNC forming grinders, CNC optical curve grinders, CNC continuous track coordinate grinders and automatic polishing machines.
CNC measurement
The complex product structure will inevitably lead to the complexity of the shape of the mold parts. Traditional geometric detection methods have been unable to adapt to the production of molds. Modern mold manufacturing has widely used three-dimensional numerical control measuring machines to measure the geometric quantities of mold parts, and the detection methods of mold processing have also made great progress. In addition to the three-dimensional CNC measuring machine which can measure data of complex curved surfaces with high accuracy, its good temperature compensation device, reliable anti-vibration protection ability, strict dust removal measures and simple operation steps make on-site automated detection possible.
The application of advanced mold manufacturing technology has changed the traditional mold making technology. The mold quality depends on human factors and is not easy to control, making the mold quality dependent on physical and chemical factors, the overall level is easy to control, and the mold reproduction ability is strong.
