New technology of die design and manufacturing for

New technology for panel die design and manufacturing

at present, the important problem faced by die cars is that there are many aspects of efficiency that deserve attention and quality. Due to the acceleration of the launch of new models in the market, auto die enterprises not only need to produce dies, but also the production capacity requirements have become prominent contradictions for auto panel die enterprises at this stage. The key to solving these contradictions is technology, technological innovation and concept innovation

our company has conducted a lot of research on these problems and user needs in mold design and manufacturing, and accumulated rich practical application experience, which can help users in the mold industry solve practical problems

casting blank scanning improves the safety of programming and processing efficiency

in casting blank scanning, the technical requirements put forward higher requirements for the software: alignment of scanning or photographic point cloud, allowance but pay attention to distribution adjustment and defect analysis; In the programming process, different collision allowances shall be set for the tool bar and clamping, and the speed shall be optimized according to the allowance size to ensure that the tools and equipment can process efficiently in the case of uneven casting blank allowance, and ensure the safety of equipment and tools; The software can check the collision interference of 5-axis machining. The following is the actual part application using CopyCAD. The data acquisition and reverse blank processing of large casting model can be completed in about 2H

first collect point cloud data through camera equipment or handheld data acquisition equipment, and then input a large amount of point cloud data into the CopyCAD product module, which can process 2million point data in about 15min to quickly complete the reverse work of blank (see Figure 1)

Figure 1 from scanning point cloud to digitizing workpiece

then the data collected in the free state is self-adaptive aligned through the point cloud automatic alignment module to match the NC programming coordinate system, and the allowance allocation between the workpiece and the actual machining model is analyzed, as well as the collision relationship between the workpiece and the tool during machining. This can effectively improve the operation efficiency of the equipment and reduce the tool cost, And avoid possible equipment collision accidents, which is conducive to the realization of efficient production capacity

after understanding the information of allowance status, we need to use these conditions to optimize the speed of the actual machining process. Delcam PowerMILL can avoid collision and automatically optimize cutting speed according to the size of allowance. Based on the collision and interference function of Delcam PowerMILL allowance model, it can ensure that unattended machining can be carried out smoothly (see Figure 2)

Figure 2 the collision and interference function of the residual model based on Delcam ensures unattended machining

the scanning of the finish machining die surface and the digital lapping of on-machine inspection

obtain the forming data of the die making by means of photography or scanning, and compare the "conditions" according to the point cloud data and the theoretical CAD model to obtain the deviation data. This process does not need actual stamping and lapping, and is analyzed and processed by digital technology. In combination with Delcam's CNC machine tool quality control system (Delcam OMV), or Delcam powerinspect can be used for digital lapping. Without purchasing an extremely expensive digital lapping system, model alignment and tolerance analysis can be completed in the Delcam measurement and analysis system. The specific steps are as follows:

1. read in the CAD model, and then read in the point data model in any format (photography, scanning, hard probe, etc.), and the software processes a large number of point clouds at the same time

2. automatically align the adaptive best fit theoretical CAD model and mold scanning point cloud with one key, and adjust the RPS function by using the testable results of the automotive industry

3. analyze the die point cloud and CAD model error globally, fully analyze the error status according to the five color point cloud, provide relevant data to the NC machining, process personnel and fitter assembly personnel, and quickly determine the further process scheme. At the same time, it can predict the stamping die assembly through virtual means, which is of positive significance to greatly reduce the mold test cycle. Figure 3 shows a variety of error analysis and expression methods

Fig. 3 various error analysis and expression methods

4. "on machine inspection" (OMV) solution is an off-line programming software system used in the NC machine for automatic measurement of free-form surface and geometry. With in machine inspection, the users of manufacturing enterprises can easily control the product accuracy in the initial processing, semi finishing and other stages. In the processing process, when the parts are not removed from the CNC machine tool, they can make "wise" decisions on whether to continue and rework in the manufacturing process. By monitoring the quality of machined parts at each stage of machining, a lot of machining time can be saved. It can find any error in machining as early as possible and correct it as soon as possible, thus greatly reducing the cost. The system can output various forms of data reports compared with theoretical CAD models, and can detect the mating surface for lapping

efficient measurement and analysis automation of parts

1. obtain the elastic deformation trend line of the cover parts according to the empirical data or simulation system data, and "over correct" the possible change trend of the parts according to the empirical data before the mold manufacturing. After the mold manufacturing is completed and the elastic deformation of the pressure parts meets the design requirements, the geometric adjustment in this way can adopt the deformation simulation function of Delcam powershape to define the influence area, Geometric adjustment for given deformation conditions (see Figure 4)

Figure 4. Based on the simulation system, the elastic back change geometry adjustment function

delcam powershape does not have the analysis function of elastic back change. It can give deformation conditions according to other simulation software data or empirical data

2. this function can also be used to supplement and adjust the process and quickly modify the process for analysis during stamping simulation to avoid repeated modeling. As shown in Figure 5, when modifying the draft angle of the dark line area, the traditional mode must be completed by re modeling, which is a lot of time-consuming. However, the global simulation deformation function can be used to quickly complete it in an instant

in Figure 5, it is necessary to modify the draft angle along the dark line area

3. carry out rapid model process treatment for the defective area found after stamping analysis, without re modeling, just return to the process designer or department, quickly modify the workpiece by imitating the deformation function, and then analyze again. The process can be repeated many times. This tool can quickly deal with the process defects in the problem area and quickly adjust the model

finish machining die surface scanning to secondary NC machining

use powershape's simulation deformation function to compare and analyze the deformation curve according to the scanned data and CAD model to simulate deformation, and then carry out secondary NC machining. The specific implementation may be difficult, thus increasing the mold making cycle. The main reason for this method is that the current analysis field can not well solve the analysis of warping deformation of panel parts, which often needs to be handled according to the long-term accumulated experience of enterprises

parametric die structure design and one click structural plane programming

this process usually takes a lot of time. In order to realize rapid process supplement and standard part design, powershape has developed a professional panel die design module. This software is easy to master the application skills. It only needs about 3 ~ 5 days of training, and the operators can undertake mold design and rapid process supplement. This not only makes the process supplement and mold standard part design can be completed in one day, but also makes the paperless manufacturing possible

unmanned and efficient machining

unattended machining in the NC machining workshop is a high-level stage pursued by the industry. FAW mold company has implemented unattended machining, tool life management and NC programming Safety specifications in the panel NC machining workshop based on PowerMILL two years ago. Based on the establishment of programming specification, the accumulation of automobile panel manufacturing knowledge base based on PowerMILL platform is realized, and human errors are minimized. For unmanned NC machining, Delcam PowerMILL has its advantages and is also the flagship product of Delcam company. After years of development, the product has been greatly improved. It focuses on the development of cam field and has certain expertise in the field of panel mold design

multithreading technology and background computing technology

automobile mold enterprises pay attention to efficiency and cost. The new version of powermill10.0 can be better combined with new computer technology. It adopts multithreaded computing, multi CPU and supports background computing, which more effectively improves programming efficiency and processing efficiency. It has strong advantages in the design and manufacturing of large mold products such as automobile panels and interior trim parts (see Figure 6)

Figure 6 supports larger memory, system background operation and system management

if a traditional software without multithreading and background operation is used, programmers can generate 5.5h tool path within 8h a day, including thinking, experiment and post-processing. If the computer has the ability of multi-threaded computing, programmers can still work while the computer is computing. Multi threading can ensure faster computing speed and higher precision. With the improvement of computer capability, the software can do better in terms of safety and tool path optimization. The optimized path can be combined with the motion performance of the machine tool to minimize the speed loss and improve the processing efficiency of the NC machine tool by more than 15%

conclusion

based on the above, it is very important to adopt more advanced technology to effectively improve production capacity and solve the bottleneck problem of enterprise development to a certain extent at different stages of automobile mold development. At the same time, it is also something that enterprises should do sooner or later to investigate and adopt new technologies that can improve the efficiency and quality of NC machining in the panel mold manufacturing industry