Research On A Parameterized Cad System For The Threaded Connector

In order to adapt to the high-speed development of China’s railways, the railway vehicle enterprises urge to short the develop circle of locomotive vehicle products, improve the design efficiency and ensure the safety of the operation. Threaded connection is widely used in the rolling stock industry. According to different practical problems, different customers have different requirements on the performance, parameters and materials of the threaded connection. Generally, threaded connection’s parameters are got from the specific standards, and there is a certain constraint relation between different parameters. So the parameterized CAD system for the threaded connector can be achieved by the application of the database technology.This system use Visual C＋＋as the programming tools and SolidWorks2010as the software development platform. And this system is achieved by using the COM component technology and the parameter-driven method. The system establishes a Access database according to the relevant standards. The system can assess data-base and manage the parameters of the model by using ADO database interface technology. So the system can avoid the irrationality on updating the parameters manually. Users only need to select the required data in corresponding interactive interface, can quickly get the solid model and carry on the related research work.Based on the motor hanging bolt group of a certain type of vehicle as an ob-ject, using the moment equilibrium and deformation coordination conditions, this article put forward a method to transform the bolt group model into a single bolt coupling model which is applicable to VDI2230criterion. By this method, users can determine the working condition of different bolt of the bolt set, on which the bolt bears the maximum static load or the maximum cyclic load. Then, according to VDI2230criterion, users can assess whether the static strength and fatigue strength of different bolt meet the design requirements. Also this system has de-veloped a plug-in based on the principle of the criterion, which can calculate the equivalent working stress calculation of bolts. Users can check the strength of the bolt quickly by using the plug-in provided by the system. In addition, the aiticle compares the results by using VDI2230criterion with the results based on the fi- nite element analysis, it illustrates that this research adaptes to VDI2230criterion.The system has established the finite element model in the software of AN-SYS through the steps of modeling, meshing, etc. At the same time, the system has defined the contact pairs between all areas of the entire model (especially for threaded portion), on which the contact behavior maybe occur. The article deter-mines the corresponding external load through the analysis of the working condi-tion, the pretension force according to the method of controlling pretension force by moment. Then, the article can get the stress nephogram of the different bolts on different working conditions after applying constraints and solving. The static strength of bolts can be checked according to the stress nephogram of specific conditions. Then, the article verify that this research adaptes to VDI2230criterion through comparing its results with the results based on the VDI2230criterion. In addition, the article also assess whether the fatigue safety factors of the bolts meet the design requirements by using the strength check formula, after the steps of extracting node solutions of key parts and processing the data.In conclusion, the system can not only improve the design efficiency of threaded connection, but also can provide the solid model and the concise calcu-lation interface for the following structure design and strength analysis.