Experimental and FEM-based Analysis of the thermal loads in deep-hole drilling process using twist drills and MQL

使用麻花钻和 MQL 进行深孔钻削过程中热载荷的实验和基于 FEM 的分析

• 批准号: 178784593
• 负责人: Professor Dr.-Ing. Dirk Biermann
• 金额: --
• 依托单位: Institut für Spanende Fertigung
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2016-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/178784593?language=en
• 关键词: Experimental; FEM; based; Analysis; thermal

The main aim of this project is the development of a high-efficient finite-element-simulation, in order to predict the thermally induced workpiece deviations in deep-hole drilling of complex aluminium cast alloy components using twist drills and minimum quantity lubrication (MQL) as well as to develop appropriate compensation strategies and to minimize the experimental effort. Due to this central objective, two different focuses have been defined within this third and last stage of the priority program (PP) 1480. The first emphasis is the implementation of a high-precision and with regard to the computing time optimized 3d-simulation of the drilling process, in order to achieve realistic calculated thermally and mechanically induced workpiece deformations during and after the machining process. Further enhancements of the model should also be able to map the borehole straightness deviation which remains after cooling down of the workpiece. The second aim of the project is the development of three innovative compensation techniques, which are fundamentally different and offer diverse advantages and disadvantages so that a combination of the strategies seems to be reasonable, too. At first, the process adaptation of the feed / the feed velocity / should be analyzed, since a higher feed rate not only induces a lower thermal load into the workpiece, but also allows higher productivity. In terms of the coolant concept, the MQL should be used furthermore within the project. The compensation of the thermal load is carried out by cooled compressed air, which is a reasonable alternative to the cryogenic concept, because of its advantages regarding to the handling, operational safety etc. Cryogenic cooling is frequently used in machining of hard-to-cut materials. The third compensation strategy is based on the synchronous radial movement of the machine tool spindle during the axial feed of the tool. Due to this NC-path compensation, the drilling axis can be modified over the machining process and the drilling direction can be controlled. Apart from the fundamental investigation of these compensation techniques the developed solutions will be transferred to complex application oriented demonstration components. At the end of this third and last stage of this project within the PP 1480 a holistic methodology of the analysis, modelling, simulation, prediction, and compensation of the thermally induced workpiece deviations will be presented.

该项目的主要目标是开发高效的有限元仿真，以预测使用麻花钻和微量润滑 (MQL) 进行复杂铝合金铸件深孔钻削时的热致工件偏差以及制定适当的补偿策略并尽量减少实验工作。由于这一中心目标，在优先计划 (PP) 1480 的第三个也是最后一个阶段中定义了两个不同的重点。第一个重点是实施高精度并针对计算时间优化的 3D 模拟钻孔过程，以便在加工过程中和加工后实现实际计算的热和机械引起的工件变形。该模型的进一步增强还应该能够绘制工件冷却后残留的钻孔直线度偏差。该项目的第二个目标是开发三种创新的补偿技术，它们本质上是不同的，并且具有不同的优点和缺点，因此策略的组合似乎也是合理的。首先，应分析进给/进给速度/的工艺适应性，因为较高的进给速度不仅会降低工件的热负荷，而且还可以提高生产率。就冷却剂概念而言，MQL 应在项目中进一步使用。热负荷的补偿是通过冷却的压缩空气进行的，这是低温概念的合理替代方案，因为它在操作、操作安全等方面具有优势。低温冷却经常用于难切削材料的加工材料。第三种补偿策略是基于刀具轴向进给过程中机床主轴的同步径向运动。由于这种 NC 路径补偿，可以在加工过程中修改钻孔轴并控制钻孔方向。除了对这些补偿技术的基础研究之外，开发的解决方案还将转移到复杂的面向应用的演示组件。在 PP 1480 内该项目的第三个也是最后一个阶段结束时，将提出对热引起的工件偏差进行分析、建模、模拟、预测和补偿的整体方法。