【中文摘要】 环件冷辗扩是一种先进的连续局部塑性回转成型工艺,具有节能、节材、生产效率高、生产成本低、产品质量好等优点,广泛用于生产各类轴承套圈、齿圈、管接头以及其他精密无缝环件。目前,对于形状简单的矩形截面环件冷辗扩理论及工艺设计方法的研究已取得了丰富的成果,实际生产也很成功。而异形截面环件冷辗扩的研究则相对滞后,实际成产中存在较多技术难题。本文以双沟轴承外圈为研究对象,从理论、数值模拟和实验角度对双沟轴承套圈冷辗扩成型基本规律进行了深入研究。本文在矩形截面环件闭式辗扩力能公式的基础上,采用微元法推导了适合双沟截面环件的辗扩力能公式。针对双沟环件冷辗扩金属变形的特点,将其辗扩过程分为两个阶段,通过适当的假设,推导了双沟环件在辗扩不同阶段的外径增长表达式。对导向辊控制方式进行了研究,得到了导向辊圆心运动轨迹分别为直线和圆弧两种情况下的运动方程。针对芯辊进给规范,研究得到了辗扩对象为双沟截面环件时,采用芯辊进给速度为常数、每转进给量为常数、环件外径增长速度为常数和导向辊圆心运动速度为常数这四种控制条件下的芯辊进给速度设计方法。基于环件辗扩理论与工艺设计方法,通过对双沟截面环件辗扩工艺特性分析,设计了双...更多沟环件冷辗扩中的各项工艺参数,包括毛坯尺寸、模具尺寸和芯辊进给速度等。基于ABAQUS/Explicit有限元分析软件,建立了双沟轴承外圈冷辗扩过程的有限元分析模型,对双沟轴承外圈冷辗扩成型过程进行了数值模拟,重点研究了环件沟道区域的受力状态、金属流动规律及应力应变关系。采用不同的毛坯尺寸和芯辊进给速度进行数值模拟,分析对比了不同参数下的冷辗扩成型情况,得出了最优工艺参数。基于优化工艺参数,在D56G90精密冷辗扩机上进行了双沟轴承外圈冷辗扩实验研究。通过合理调试设备控制参数,成功使用矩形毛坯辗扩出合格的双沟轴承外圈,并和模拟结果进行对比,验证了工艺的可行性和数值模拟的正确性。
【英文摘要】 Cold ring rolling is an advanced continual local plastic rotary forming technology, which has the advantage of energy and material saving, high productivity, low production cost and high quality, etc. It has been widely used to manufacture various precise seamless ring shape parts such as bearing race, gear ring and pipe junction.At present, abundant research achievements have been obtained about simple rectangular cross-section ring's rolling theory and process planning method, practical production is also successful. But the research on cold ring rolling of irregular section ring is relatively backward, there are many technical problems during production process. So this paper is related to the study of basic forming principles of cold rolling for double groove ball bearing outer rings from theory, numerical simulation and experiment.In this paper, the force-energy formula which is suitable for double groove ball section ring is deduced based on force-energy formula of closed rolling... of rectangular cross-section ring by using micro-element method. Considering fully metal deformation characteristics of double groove ball ring rolling, its rolling process is divided into two phases at appropriate hypothesis, then deduced the outer diameter growth expression of double groove ball ring at different stages of rolling process. Two kinds of motion equations are obtained respectively from the straight line and arc trajectory of guide roller center by researching control mold of guide roll. As feed specification of idle roller is concerned, the feed speed design methods are obtained respectively under four conditions of controlling molds, which are feed speed of idle roller is constant, feed per revolution is constant, outer diameter growth speed of ring is constant and motion velocity of guide roller center is also constant.Based on ring rolling theory and process design method, related process parameters are designed through the analysis about characteristics of double groove ball ring rolling, including ring blank size, mould size and feed speed of idle roller, etc. The 3D finite element model of cold ring rolling for double groove ball bearing ring is established based on ABAQUS/Explicit software platform, the cold ring rolling process is also simulated. Then mainly studies the force condition, metal flow law and stress-strain relationship in ring groove zone. Taking different ring blanks and feed speeds of idle roller into simulation, the optimal process parameters are obtained through analysis and comparison for forming results under different process parameters.The experimental investigation of cold ring rolling for double groove ball bearing ring is conducted in D56G90 precise rolling machine by using optimal process parameters. Through adjusting control parameters of this equipment, the qualified product is manufactured successfully by using rectangular cross-section ring. The experiment results is compared with the simulation results to verify the feasibility of this technology and correctness of numerical simulation.
【中文关键词】 冷辗扩; 双沟轴承; 数值模拟; 工艺设计
【英文关键词】 Cold ring rolling; double groove ball bearing; numerical simulation; process design
