共查询到19条相似文献,搜索用时 156 毫秒
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在直齿圆柱齿轮两步成形冷精锻工艺中 ,预锻模具齿形设计对改善材料填充性能 ,降低成形载荷具有重要意义。本文采用正交试验法与数值模拟技术相结合的方法 ,来解决预锻模具型腔优化设计问题。选取了描述预锻模具几何形状的 3个参数作为影响因素 ,以预锻终锻总载荷值为指标 ,通过有限元模拟分析来获得虚拟试验结果 ,最终确定预锻模具型腔几何形状参数的最佳值 ,为提高齿轮精锻成形质量提供有效依据。 相似文献
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转向螺母是汽车上复杂异形非圆齿形零件,结构形状复杂,需要多个方向产生变形,各部分变形量不同,成形难度大。在分析其结构形状特点和成形难点的基础上,提出了多向联动加载成形工艺。该工艺在成形过程中,各凸模加载顺序、速度、行程根据材料流动和充填情况进行联动控制,控制材料主动向需要的地方流动和填充,进而提高材料充填性和降低成形力。利用有限元软件对该工艺成形过程中的金属流动规律、材料填充状况、应力分布、成形力进行了数值模拟分析。对转向螺母的多向联动加载成形工艺和顺序加载成形工艺进行了对比分析,多向联动加载成形工艺比顺序加载成形工艺成形力降低了28%。对多向联动加载成形工艺进行了成形试验,成形出的转向螺母充填饱满,尺寸符合图纸要求,未出现锻造缺陷,并进行了小批试制。试验结果表明该工艺具有可行性和实用性。 相似文献
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齿轮滚轧是一种新型齿轮成形工艺,具有生产效率高、材料利用率高、轮齿机械性能好等优点。由于缺乏对带强制分齿的轴向滚轧工艺的研究,提出了带强制分齿的轴向滚轧工艺的数值模拟方法,并通过滚轧实验进行了验证。由于软件无法定义齿坯的主动旋转运动,推导了以轧轮公转代替齿坯自转的运动学模型,在有限元软件FORGE中建立了齿轮轴向滚轧有限元模型,从金属流动、应力分布等方面分析齿坯成形过程;最后,进行齿轮轴向滚轧实验,结果表明成形齿轮的齿形与数值模拟结果比较吻合,证明了运动学等效模型的正确性以及有限元方法的可行性。 相似文献
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对螺旋角为20°和30°的圆柱斜齿轮的滚轧成形工艺进行了研究。依据体积不变原理,在确定齿坯直径的基础上计算了滚轧轮齿顶圆直径、齿形尺寸等;利用有限元软件DEFORM-3D仿真分析了圆柱斜齿轮在滚轧成形过程中金属的流动规律和等效应变场。 相似文献
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基于UG的双联齿轮参数化设计 总被引:1,自引:0,他引:1
双联齿轮的齿形轮廓形状复杂,参数驱动化设计困难,文中运用参数化三维软件UG.对圆柱直齿轮进行三维建模。通过模型模块中的规律曲线,建立齿形轮廓,通过与齿根圆柱布尔运算、拉伸、引入特征阵列等命令,建立双联齿轮三维模型,达到了改变基本参数,立即得到相应的双联齿轮三维模型的参数化驱动化设计。 相似文献
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结合冷滚打成形工艺的特点,基于Python语言对有限元分析软件ABAQUS进行二次开发,建立了冷滚打成形有限元模型的参数化建模插件,利用该插件可以对滚打轮和工件的几何模型、复杂材料属性以及打入深度、公转速度、进给速度等工艺参数进行便捷更改,实现冷滚打有限元仿真模型的参数化建立,自动完成几何建模、网格划分、材料属性定义到提交作业等一系列前处理过程,最后使用该插件进行了仿真模拟,并进行了冷滚打试验研究,对不同转速下的仿真成形力和齿形轮廓与试验进行了对比分析。结果显示:仿真所得成形力和齿形轮廓与试验都有相同的变化趋势,并且误差都控制在6%以内,验证了利用该插件建立冷滚打有限元模型的可行性和有效性。 相似文献
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T. S. Yang N. C. Hwang S. Y. Chang 《Journal of Mechanical Science and Technology》2007,21(10):1566-1572
The manufacture of gears by applying hot or cold bulk forming processes is a quite widespread production method due to its
well-known basic advantages such as material and time cost reduction and the increased strength of the teeth. However, the
associated process planning and tool design are more complicated. In the precision forging of gears, the workpiece volume,
the die design, the power requirement and careful processing are more critical than traditional forging technology. For complete
filling up, predicting the power requirement is an important feature of the near net-shape forging process. In this paper,
a finite element analysis is utilized to investigate the material properties such as yielding stress, strength coefficient
and strain hardening exponent effects on forming load and maximum effective stress. The adductive network was then applied
to synthesize the data set obtained from the numerical simulation. The predicted results of the maximum forging load and maximum
equivalent stress of bevel gear forging from the prediction model are consistent with the results obtained from FEM simulation
quite well. After employing the prediction model one can provide valuable references in prediction of the maximum forging
load and maximum equivalent stress of bevel gear forging under a suitable range of material parameters. 相似文献
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直齿圆柱齿轮精锻成形过程数值模拟及参数分析 总被引:5,自引:0,他引:5
采用三维有限元数值模拟方法分析了直齿圆柱齿轮的精锻成形过程,选择模拟表面单元数、加载步长、模数、齿数、齿轮高度等参数进行了多次模拟分析,根据模拟结果对比分析了以上诸参数对成形工艺的影响。确定了适宜的表面单元数目和加载步长值,较好地满足了模拟的需要。从数值模拟结果分析可知,在齿轮其他参数不变的情况下,锻造载荷随模数和齿数的增加而增加,模数的变化对载荷的影响显著;在对高度不同的齿轮成形过程的模拟分析中发现,在成形的初始阶段,高度越小载荷越大,在填充终了阶段,随高度增加载荷稍有增加。 相似文献
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In the manufacture of straight bevel gears, a precision forging method has been mainly used in recent years and the precision forging die has been usually manufactured using electric discharge machining. However, it is difficult to content the high productivity and low manufacturing cost using electric discharge machining because the gears are produced through a process of several steps. In this article, a design and manufacture of a straight bevel gear for a precision forging die by direct milling is developed in order to improve the productivity and manufacturing cost for the gear production. The tooth profile of a straight bevel gear generated by a quasi-complementary crown gear instead of a usual complementary crown gear is introduced. For this study, first the numerical coordinates on the tooth surface of the straight bevel gear were calculated and the tooth profiles were modeled using a 3D-CAD system. Afterward, the direct milling of the precision forging die of the straight bevel gear in the hardened state was carried out using a CNC milling machine based on a CAM process through the calculated numerical coordinates. 相似文献
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通过对汽车半轴锥齿轮冷摆辗精密成形技术进行研究,重点剖析了半轴锥齿轮毛坯的锻造工艺、冷摆辗成形工艺参数的选择、模具结构设计、金属切削加工和表面最终热处理等一系列关键技术,结果表明,采用冷摆辗精密成形技术的半轴锥齿轮具有精度高、强度高、啮合性能好,齿轮模具寿命长,材料利用率高,生产成本低等优良性能. 相似文献
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Half axle gears is produced by precision forging popularly because of the advantages in minimum machining allowances, lower material consumption and good service properties. But the forming quality of precision forging is difficult to control. Many simulations and analysis of precision forging process were taken by previous researchers. But no concrete method is proposed to evaluate and optimize the forming quality of half axel gears. The primary purpose of this work is improving the forming quality of half axel gears by analyzing and optimizing the affected factors of forming quality. The enclosed-die warm forging process of half axle gears was developed, and a new type of die-set used on double action hydraulic press was brought forward. The main influential factors of precision forming quality were analyzed after the forming process had been simulated by using finite element method(FEM). These factors include die structure, web thickness and web position. A method used to evaluate the forming quality was established, which investigated the maximal forming load, the metal filling rate and the material damage factor. The FEM simulations of half axle gears precision forging were evaluated by this method. The results show that the best forming quality can be achieved when the punches were added with bosses, the web located at the middle plant of the gear, and the web thickness was 30 percent of the inner hole diameter. Verification experiments taking the above optimized parameters were performed on a 7.8 MN double action hydraulic press. The trial products were formed well. And their geometric precision meets the demand. The verification result shows that the optimization of the influential factors, according to the simulations and the evaluation method, can improve the forming quality. The new structure of precision forging die-set and the new evaluation method guarantee a high forming quality of half axel gears. 相似文献
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汽车差速器锥齿轮的温锻制坯/冷摆辗成形加工技术研究 总被引:5,自引:0,他引:5
为提高差速器锥齿轮的齿部强度和静啮合特性,达到少无切削加工及大批量生产的目的,采用温锻制坯、锻件余热退火与冷摆辗成形相结合的精密成形工艺生产差速器锥齿轮精锻件;对变形程度的分配、成形工艺参数的选择、高精度冷摆辗模具的设计与加工等关键技术问题进行了分析。结果表明,采用该工艺生产的差速器锥齿轮精锻件,较好地解决了差速器锥齿轮制造过程中存在的齿轮精度差、齿部强度低、模具寿命低、设备投资大等问题,为提高差速器锥齿轮的国产化率、减轻差速器的重量进而减轻汽车的自重等奠定了技术基础。 相似文献
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In this paper, the forging of helical gears has been investigated. A punch and a die are tooth-shaped for the guiding type forging of helical gears. The punch compresses a cylindrical billet placed in a die insert. As a consequence the material of a billet flows into the tooth region. The forging has been analysed by using the upper-bound method. Kinematically admissible velocity fields have been developed, where an involute curve has been introduced to represent tooth profile of the gear. Numerical calculations have been carried out to investigate the effects of various parameters, such as modules, numbers of teeth, helix angles and friction factors on the forging of helical gears. Some forging experiments were carried out with commercial aluminium alloy to show the validity of the analysis. Good agreements were found between the predicted values of the forging load and those obtained from the experimental results. 相似文献