钨钴类硬质合金球行星研磨及其装备研究

【作者】 文灏；

【导师】 刘舜尧；

【作者基本信息】 中南大学 ， 机械工程， 2010， 硕士

【摘要】 高精度钨钴类硬质合金球主要用于石油钻探抽油泵阀球。硬质合金球和钢球的主要不同是硬度高,与陶瓷球的主要不同是密度大。传统研磨加工生产工艺因受人为因素的影响,一致性和稳定性较差,加工成本高,难以获得高球度的硬质材料球。双自转、三自转研磨方式目前尚停留在实验研究上,在批量生产上的质量控制和设备维护还是难题,而且其设备电气控制系统复杂,制造费用和维护费用比较昂贵。针对钨钻类硬质合金球的高精度、高效率加工,本文提出了一整套高效精密加工技术方案,采用V型槽冷压孕镶金刚石与平面砂轮行星研磨加工方法进行粗加工,采用三行星盘行星研磨方法进行精加工。通过行星研磨运动原理分析、材料去除过程分析和研磨轨迹仿真证明了该套方案的可行性。全文围绕行星研磨加工方法的基础理论、关键技术和设备结构改进展开研究,分析了球坯的几何运动,通过无打滑研磨运动分析和坐标变换建立了行星研磨运动的数学模型,运用MATLAB仿真研究了研磨过程中球坯运动轨迹和自转角的变化规律,论证了三行星盘行星研磨加工技术的可行性,建立了行星研磨加工的数学模型,分析了研磨过程中单球球度误差修正过程、批球球径一致化过程。提出了利用3ML4780立式钢球研磨机改进为三行星盘行星研磨加工装置的设备结构方案,实现了机床粗精加工设备的互换性,为协调生产和节约设备成本创造了有利条件。分析了行星研磨加工的工艺影响因素,进行了Φ34.925mm的YG13钨钴类硬质合金球的粗磨、精研工艺试验研究,通过正交试验,以直径去除率、平均球度改进量和批直径一致性改进量为指标进行评价,对行星研磨加工的工艺参数进行了优化。本文关于钨钴类硬质合金球的行星研磨运动原理分析、三行星盘研磨设备及其研磨工艺的研究对于生产高精度硬质合金球具有工程应用价值和工艺理论意义。更多还原

【Abstract】 High-precision Tungsten-cobalt cemented carbide balls are mainly used by the petroleum drilling pump’s valve ball and so on. The cemented carbide balls’main difference from steel balls is their high hardness, however, their main difference from ceramic ball is their high density. By the impact of human factors, the traditional lapping process of the cemented carbide balls got low precision and effieiency, low uniformity and stability, high processing costs. Double(or three) variable rotation lapping methods are still at the experimental research period. There are problems in the manufacture’s quality control and the high precision equipment’s maintenance. The machine’s electrical control system is very complex, and its manufacturing and maintenance costs are very high.The paper puts forward a set of high-precision machining technology to realize Tungsten-cobalt cemented carbide balls’high-precesion and high-efficiency machining. Uses planetary grinding method, by a cast iron plate with V-groove inlayed diamond and a diamond-resin plate, to do coarse process. Puts forward a new finish machining technology-three-planets planetary lapping method. Demonstrates the feasibility of rough and finish processes by analysising the principle of planetary lapping and the process’s material removal, and by simulating the balls’ lapping track.The paper around the planetery grinding method’s foundamental theory, key technology and lapping equipments and tools, by analysising the balls’movement on the premise of no slipping and by coordinate transformating, sets up the planetary lapping method’s mathematical model, uses MATLAB to simulate the lapping trace and self-rotation angle’s changing regulation, demonstrates the three-planets planetary lapping method’s technical feasibility, establishes the mathematical model of planetary lapping, analysises the single ball’s spherical error correcting process and the batch balls’diameters uniformating process.The paper puts forward a improved lapping machine’s structure, to improve 3ML4780 stand-style steel ball lapping machine to three-planets planetary lapping machine,to realize the interchangeable between coarse machine and finish machine, to create favorable conditions to coordinate manufacture and to reduce machine’s innovating cost.The paper studies the impact facts of planetary lapping process, has done many tests to coarse process and finish process by using YG13-grade 34.925-millimeter diameter cemented carbide balls, optimizes the lapping process’s technical parameters by the diameter’s reducing rate and the average roundness’s modification and the bateh uniformity’s modification.The research, of the principle of tungsten cobalt cemented carbide balls’planetary lappping, of the three-planets planetary lapping equipment, and of the lapping experiment technology, has great value in engineering and has importent process theoretical significance for manufacturing high-precision cemented carbide balls.更多还原