整体叶盘构件数控磨削工艺关键技术研究

发布时间：2018-05-01 18:43

本文选题：磨削加工 + 整体叶盘　；参考：《西北工业大学》2016年博士论文

【摘要】：随着整体叶盘结构件在航空、航天、船舶、能源、核工业等领域的重大装备中得到广泛应用,其加工制造工艺技术也得到飞速发展。但是,相对于目前已经成熟的整体叶盘构件粗加工工艺技术,其精加工磨削工艺依然处于落后的人工打磨阶段,人工经验打磨质量一致性差、均匀性差,且加工效率十分低下,不仅影响整体叶盘结构件的疲劳寿命,而且制约发动机的生产制造周期。因此,开展整体叶盘自动化磨削技术研究,建立其高效可靠的磨削工艺方法,以摆脱传统落后的人工打磨工艺方法,对提高整体叶盘疲劳性能和生产效率、研究和建立自动化生产线的等都具有十分重要的意义。本文针对整体叶盘结构件人工打磨工艺质量差、效率低等问题,基于自主设计的整体叶盘数控磨削实验平台,通过分析整体叶盘磨削工艺中面临的问题挑战,开展整体叶盘数控磨削工艺关键技术研究,深入研究磨削过程中的接触状态、磨削力状态、磨削工艺条件等,并结合工艺实验验证理论分析的可靠性,论文的主要研究工作与获得的主要结论如下:(1)基于整体叶盘结构特点,分析整体叶盘磨削加工中面临的主要难点与问题,结合人工打磨加工方法经验,并考虑其后续一体化自动生产线的设计建立,提出适应整体叶盘特点的数控磨削加工工艺方法,分析说明整体叶盘数控磨削实验平台的结构及组成部分,并着重对磨削实验平台的柔性磨削主轴机构展开深入研究,阐述其结构特点与装配形式,对该关键机构的工作原理进行说明,建立其工作范围与工作位姿的理论计算公式,最终形成整体叶盘自动化磨削加工工艺理论方法。(2)依据数控砂带磨削工艺基础理论知识,对磨削工艺过程中磨具与工件之间的接触状态进行理论分析,主要包括接触区域特征、接触区域压力分布状态、材料去除率等内容研究,采用接触加工实验,分别研究磨料粒度、磨具接触曲率、主轴转速、理论磨削深度、工件曲率半径等因素对接触区域特征的影响规律,并基于赫兹弹性接触理论,从凸面接触与凹面接触两个方面,分析并建立磨削接触区域各点处的压力分布状态方程,最后进行基于Preston方程的磨削加工材料去除率模型研究,分别得到凸面接触与凹面接触形式下的材料去除率方程,并获得材料去除率方程修正系数,实验结果表明材料去除率模型具有较高的可靠性。(3)分析说明整体叶盘磨削工艺过程中磨削力的作用形式,依据传统砂带磨削法向磨削力经验公式,并基于数控磨削实验平台柔性主轴机构的工作原理,提出磨削力间接控制方法,对间接控制过程进行理论分析、简化并建立控制系统数学模型,而且充分考虑实际系统中存在的非线性、不确定性、不稳定性、复杂性等因素,采用模糊PID算法对系统进行控制,选用变角度三角隶属函数,建立其模糊控制规则,对控制系统进行仿真分析,并与传统PID控制效果进行对比,结果表明,模糊PID磨削力间接控制获得高响应速率、低超调量的控制效果,最后通过仿真分析负载质量对控制系统的影响情况,进一步验证控制方法具有较高的适应性和理想的控制效果。最后,通过比例阀压力传感器数据检测,建立磨削过程中法向磨削力的计算公式。(4)对整体叶盘磨削质量表征参数与加工参数进行分析,结合整体叶盘加工质量要求,选取表面完整性若干参数作为对整体叶盘磨削工艺优劣的评价指标,并开展加工参数对表面完整性指标的单因素实验研究,掌握加工参数对各指标的影响规律,进而采用正交方法设计实验,对实验检测结果进行分析处理,建立表面完整性各评价指标的指数经验公式,最终展开磨削工艺过程加工参数优化,将优化问题进行线性处理并提出约束条件,获得在不同目标函数下的优化磨削加工参数组合。(5)分别展开磨削工艺中实际磨削深度、磨削力控制、加工参数优化等研究内容的加工实验验证,实验结果证明了磨削关键机构对主轴位姿微位移调节的有效性、模糊PID控制方法对法向磨削力间接控制的可靠性等;同时实验结果表明,磨削力控制加工质量明显提高,而相对于人工经验打磨与经验参数磨削加工,在优化加工参数磨削条件下,工件加工表面质量得到明显改善,且加工效率获得显著提高。
[Abstract]:With the wide application of the whole disc structural parts in the fields of aviation, space, ship, energy, nuclear industry and other fields, the processing and manufacturing technology has also been developed rapidly. However, relative to the present mature whole leaf disk component rough machining technology, its precision grinding process is still in the backward artificial grinding order. With poor quality consistency, poor uniformity and low processing efficiency, the artificial experience not only affects the fatigue life of the whole leaf disc structural parts, but also restricts the production cycle of the engine. Therefore, the research on the automatic grinding technology of the whole leaf disc is carried out and the high efficiency and reliable grinding process is established to get rid of the traditional backward people. It is of great significance to improve the fatigue performance and production efficiency of the whole leaf disc and to establish the automatic production line. This paper aims at the problems of poor quality and low efficiency of the artificial grinding process of the whole leaf disc structural parts. Based on the independent design of the whole body disc CNC grinding experiment platform, the whole system is analyzed as a whole. In the process of disc grinding, the key technology of the whole disc CNC grinding process is studied. The contact state, the grinding force state and the grinding process conditions are deeply studied in the grinding process, and the reliability of the theoretical analysis is verified by the experimental verification. The main conclusions are as follows: (1) the main conclusions are as follows: (1) The main difficulties and problems in the grinding process of the whole leaf disc are analyzed, and the main difficulties and problems in the grinding process of the whole leaf disc are analyzed. The design and establishment of the integrated automatic production line are set up in consideration of the experience of the artificial grinding processing method. The numerical control grinding process method adapted to the characteristics of the whole leaf disc is put forward, and the experimental platform of the whole blade NC grinding is analyzed and explained. The structure and components are studied, and the flexible grinding spindle mechanism of grinding experiment platform is studied in depth, its structure features and assembly forms are expounded, the working principle of the key mechanism is explained, the theoretical calculation formula of its working range and working position is established, and the theoretical side of the automatic grinding process of the whole leaf disc is formed. (2) according to the theoretical knowledge of CNC Abrasive belt grinding process, the contact state between the grinding tool and the workpiece in the grinding process is theoretically analyzed, including the contact area characteristics, the contact area pressure distribution state, the material removal rate and so on. The contact machining experiments are used to study the abrasive grain size and the contact curvature of the grinding tool. The influence of the spindle speed, the theoretical grinding depth and the workpiece curvature radius on the contact area characteristics, and based on the Hertz elastic contact theory, from two aspects of the contact and the concave contact of the convex surface, analyze and establish the state equation of the pressure distribution at the contact area of the grinding contact area. Finally, the grinding material based on the Preston equation is carried out. The removal rate equation of the material removal rate is obtained, and the correction coefficient of the material removal rate equation is obtained. The experimental results show that the material removal rate model has high reliability. (3) analysis shows the form of the grinding force in the whole process of grinding disc grinding, according to the traditional abrasive belt grinding method. Based on the empirical formula of grinding force, and based on the working principle of the flexible spindle mechanism of the NC grinding experiment platform, the indirect control method of grinding force is put forward, the indirect control process is analyzed theoretically, and the mathematical model of the control system is simplified and established, and the nonlinear, uncertainty, instability, complexity and so on in the actual system are fully considered. The fuzzy PID algorithm is used to control the system, and the variable angle trigonometric membership function is selected to establish its fuzzy control rules. The control system is simulated and analyzed. The result shows that the indirect control of the fuzzy PID grinding force can obtain the high response rate and the control effect of the low overshoot, and finally through the simulation. The influence of the load quality on the control system is analyzed, and the control method is further verified that the control method has high adaptability and ideal control effect. Finally, the calculation formula of the normal grinding force in the grinding process is established through the data detection of the proportional valve pressure sensor. (4) the analysis of the quality characterization parameters and the processing parameters of the overall blade grinding quality and the processing parameters are analyzed. A number of parameters of surface integrity are selected as the evaluation indexes for the grinding process of the whole leaf plate, and a single factor experimental study on the surface integrity index of the processing parameters is carried out. The influence law of the processing parameters on the indexes is grasps, and then the orthogonal method is used to design the experiment. The index empirical formula of the evaluation indexes of surface integrity is established, and the optimization of the processing parameters of the grinding process is finally carried out. The optimization problem is linearly treated and the constraint conditions are put forward to obtain the optimum grinding parameters combination under different target functions. (5) the actual grinding depth and grinding in grinding process are carried out respectively. The experimental results prove the effectiveness of the grinding key mechanism to the adjustment of the spindle position and position, and the reliability of the indirect control of the normal grinding force by the fuzzy PID control method, and the experimental results show that the quality of the grinding force control machining is obviously improved and relative to the manual work. With the experience grinding and the experience parameter grinding, the surface quality of the workpiece is obviously improved and the processing efficiency is greatly improved under the optimized grinding conditions.

【学位授予单位】：西北工业大学
【学位级别】：博士
【学位授予年份】：2016
【分类号】：TG596

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