Feedback from FEM to CAD

In the past, people could only reduce the rebound phenomenon of the board by using the target size deviation method. Nowadays. The FVM (Finite Element Analysis) simulation on the computer can be used to pre-calculate the springback of the board. In the case of the worst plate material. Both of these methods (feeding FEM results back to the CAD system) are expensive, and the latest generation of software is aimed at developing a simpler and faster way of working. This program can not only be used to compensate for rebound. The result can also be automatically fed back to the sheet CAD model. Let's do an experiment: Find a sheet of A4 size and try to bend it. It is easy to overlap the upper and lower sides of the sheet. However, once the force is withdrawn, the plate will quickly rebound: this is the so-called rebound effect. The sheet must be further exaggerated to exceed the limit of the rebound and maintain the desired shape. Plates are the most important semi-finished products in the automotive industry, so it is necessary to clarify this phenomenon. When the forming tool is removed, the sheet will deviate from the pre-designed shape due to its own material properties and stress. The existing method to eliminate this rebound effect is to calculate the rebound offset in advance, and then correct the molding tool based on the deviation between the offset and the target size. For a long time, drawings on the designer's desk have become more and more. Today, CAD (Computer Aided Design) systems can be used to draw two-dimensional or three-dimensional drawings on a computer. PLM (Product Life Cycle Management) and digital factory technology are constantly advancing, so that trial production is rarely used in sheet metal processing. . It is not uncommon to use Flex technology to improve molding tools.

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Compatible with different CAD systems: Using "thinkcompensator" software to demonstrate surface rebound problems in the automotive manufacturing process

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The meaning of color: Mixing shows the color of the tool surface in different states. The springback is compensated by the software. It is green before compensation and red after compensation.

Manual input of FEM data is expensive Today finite element analysis has been integrated in CAD data for mold design (A-grade exterior trims and structural parts) so that the calculated springback can be simulated and the model can be eliminated Then, enter the recalculated data into the CAD system. There are currently two solutions to this process: One is to manually input the FEM data to the CAD system, and then use the target coordinates obtained through the FEM simulation to compensate. . This is a very complex workflow that depends mainly on the level of detail of the operator. Because of the manual changes, there is no uniform tolerance control for the same tool. Therefore, in this case, it is not possible to repeat the change arbitrarily, that is, each time a new work step is started, it is necessary to start from the beginning. This method is also very troublesome for correcting the tools used in the subsequent processing steps, because each of these tools needs to be matched according to the complexity of the mold size. The work done by these matching jobs usually takes several days or even several weeks. The second method of surface reflection method software's defect in quality to transfer data to the CAD system is to use surface reflection method software to work. By this method, the model of the plate can be quickly modified without manually inputting data. However, this input method is still flawed: it cannot guarantee tolerance control in a global scope. And you lose the topology of the original plate model. The results can be obtained by a double data processing method: on the one hand by the FEM method and on the other hand by surface reflection software. It is based on the finite element simulation to build a table called "grid" (imagine a single entity as a grid) and the construction method. Under ideal conditions, the surface has 4 boundary points. However, the surface constructed by the mesh method does not have such a characteristic attribute: because we have obtained a manual local model, or rather, this model cannot be modified by conventional techniques. In the running process of surface reflection software, much more surface than the original CAD model can be produced, but its quality is very low. Although in this case it is not possible to expect Grade A quality necessary for the construction of a visible free surface, it is still possible to obtain surface data specific to the body of the car or the interior trim. These surfaces must have the best shape and a rather high surface quality. To control the best surface structure. Use light or zebra raster. By applying a zebra grating to the surface model, the surface roughness can be modeled as falling reflected light and recognized. Once the situation is resolved, the surface must be modified by means of the model's own control point until the light reflects on the desired shape of the surface. It is also possible to output the data required for modifying the surface onto the milling machine by means of light reflection. The probable problem with surface reflection methods is the loss of reflective images and speculation about surface quality. The more surface models there are, the less smooth the zebra crossing method will be. The new software ensures that the two solutions above the initial quality do not actually satisfy the designer. So far, they also need to spend a lot of time in the prototype development process. In addition, the quality of the work results mainly depends on the quality and level of the designers. just now. A software company near Munich developed a new solution with the help of a program called Think Compensator, which can feed finite element simulation data directly back to the CAD system. The whole process is automatic. It does not require hours or even days of manual labor. In addition, this software can also solve the problem of quality degradation during light reflection. Designers can determine their own tolerance points. In addition, the data can also be integrated into future work steps. What needs special emphasis is that the topological structure of the CAD model is preserved: the number of surfaces, boundaries, bending and feature attributes are preserved, and the original quality of the model is guaranteed. The software processes the original CAD data by means of a method called "shifting arrangement" and the starting/target meshes obtained by the FEM simulation. The CAD model can be modified by comparing the starting/ending conditions. In addition, this software can integrate different CAD and FEM system data together. Users can reuse this program's GSM technology (Global Forming Modeling) (this technique can be used in the “thinkiD”, which is a hybrid surface modeling software). The GSM technology makes it possible to correct the composite structure between surfaces while ensuring the quality of the transition zone. Many companies use this software, such as BMW (BMW also dominates the development of this technology), Mazda Motors, Italy's Attrezzeria Paganelli, and the US prisoner's Kyquesti Industrial. The production speed of prototypes in these companies has been significantly improved compared to before; individual repeated steps have been well circumvented. The following factors (shorter development cycle, rapid market response speed, and significantly reduced costs) are playing an increasingly important role and will further enhance the profitability of many industries including the automotive industry in the future.

Construction Hoist Steel Structure means the Construction Hoist spare parts like Construction Hoist Mast Section, Passenger Hoist Cage, Construction Hoist Wall Tie and so on. 

The length of each mast section is 1508mm, the rack is fixed on the mast by three bolts and it can be exchanged. For the single cage hoist there is only one rack on the mast section, and the mast section can be used for the double cages hoist by increasing one rack. The section of the mast is diverse, select one type section according to different hoist. The mast sections are bolted together with M24 bolts and nuts to form mast. The mast is tied to the building with tie-in and is the guide rail of the cage. According to the user`s or circumstance`s request, surface of mast is hot dip galvanized, which can prevent it rusting.

The tie-in(wall tie) is the linked part between mast and building, to keep the stabilization of the mast. Distance between the tie-in is about 6~9m alone the mast. There are several types of tie-in. Select one of them according to need, tie-in can adjust the vertical of mast in definite ranges. According to the user`s or circumstance`s request, surface of the tie-in is hot dip galvanized, which can prevent it rusting.

The cage dimension(L×W×H)(m): 3×1.5×2.5. We can also manufacture cages of other size according to the user`s needs. The material of the cage and the door material can be steel wire weave, aluminum-plastic panel, punched-plate, figured aluminum board or other type according to user`s needs. The gate is equipped with drawing gate,include small turn over gate.



Construction Hoist Steel Structure

Construction Hoist Mast Section,Construction Elevator Mast Section,Passenger Hoist Cage,Construction Hoist Wall Tie, Construction Hoist Anchorage Frame

SHEN YANG BAOQUAN BUSINESS CO., LTD , https://www.sysuspendedplatform.com

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