4 APPLICATION The method and the program are demonstrated on an example application. The geometry to be cut has a top width of 21 mm and bottom width of 63 mm with 28 mm height. The depth of the workpiece to be cut is 21 mm. The material is waspaloy, and the tool is HSS-T material. The tooth land of 3 mm and a rake angle of 12 degrees are used. The back off angle chosen is 2 degrees. R1 is 1,98 mm and R2 is 7,95 mm. The cutting speed is selected as 55 mm/sec. In the simulations, the maximum force constraint of 150000 N, and the maximum stress constraint of 1200 MPa are chosen. First, section and tool parameters were assigned in a random manner, using intuition. This is done to demonstrate the effectiveness of the method for which the results will also be presented. By running the computer program using various geometric parameters, the best solution obtained was 3 sections with total tool length of 2155 mm.  Now, the method is applied in a systematical manner. Since the geometry is simple, there is no natural geometrical constraint. As there are no geometrical constraints, the height pision is done. The algorithm is applied using given force, stress, gullet-chip volume ratio and other practical constraints. The pitch is taken as at least 1.5 times of the tool land (a=1.5). Maximum cutting tooth number is 5. The other parameters are given in Table 1. The simulated total force and stress are shown in figure 7 and figure 8. For this geometry and given constraints, this is the best solution. Some modifications can be done based on different requirements.  Also, some extra constraints such as number of sections, section volume, heights or different tooth rise values can be asked for based on practical and quality considerations. Obviously, these may increase the tool length.   5 CONCLUSIONS Broaching is a common machining process. The quality and the productivity in this process heavily depend on the tool design which defines the cutting conditions. A procedure is described for optimal design of the broach tools. The shortest possible broach tool is designed by considering the geometrical and physical constraints. This procedure can be used in optimal design of broaching tools. The results indicate that the procedure proposed here may yield to much shorter tool lengths than the ones designed intuitively.  

摘要拉削是一种非常常见的加工零件内部或外部复杂形状的制造过程。由于几何参数、 拉削工具是最关键的拉削工艺。因此, 提高生产力需要优化设计工具这个过程。在本文中,一个方法论提出了尊重几何和物理约束的拉削工具。也已在计算机上实施了该方法代码。

毕业论文关键字拉床、 优化、 模具

1 介绍

拉床通常用于加工内部或外部复杂的配置文件，很难通过生成其他如铣削和车削的加工过程。最初，拉床被开发了为圆内部配置文件和键槽。过程是非常简单的，并在减少需要有才华的机器操作员的同时，也提供高了生产速度和质量。因为笔直的非圆形运动,在非常高质量的表面可以得到完成。此外，粗加工和精加工可以一次减少共完成操作周期时间。最大的缺点是扩孔过程的不灵活性方面的工艺参数。在扩孔,所有的加工条件,除了速度,定义了工具几何形状,因此,一旦一个工具是什么设计不可能改变任何过程参数，如深度削减或芯片厚度，这是工具设计的最重要的方面拉削过程。为提高生产率和部分质量以及降低过程成本，拉刀工具必须适当地设计。在本文中,一个方法最佳设计的拉削工具与应用提出了。这种方法可以用于优化设计拉削工具对于一个给定的部分几何和材料。源'自^优尔;文,论`文'网]www.youerw.com

优化过程具有尊重物理和进程的限制。通常拉削到配置文件被加工成指定部分。然而，它是可能生成相同的配置文件使用多个不同组合拉刀用不同工具节几何图形。因此，第一次所有的节数和每一节的基本齿配置文件必须是选定。此外，刀具几何形状和参数，这种作为牙上升，沥青等，使每个部分有定义。考虑可能性的数量，需要有为一种实用方法优化设计的拉削工具这是本白皮书的主题。 拉削工具设计的优化英文文献和中文翻译(6):http://www.youerw.com/fanyi/lunwen_56433.html