共查询到19条相似文献,搜索用时 15 毫秒
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采用均匀设计方法和有限元技术对某翼子板在拉深成形过程中的摩擦系数、压边力、冲压速度等工艺参数进行了优化设计,经过优化后的仿真结果在提高成形裕度和抑制厚度的变化方面取得了良好的效果。通过与实冲板料厚度测量结果的对比,验证了优化效果。该方法还可明显减少模拟计算次数、提高优化效率、改善板料冲压成形的仿真计算精度。 相似文献
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车身碰撞盒的回弹试验研究 总被引:1,自引:0,他引:1
选择压边力、板料初始尺寸、润滑条件作为试验参数对U形车身碰撞盒进行了冲压成形生产试验,测取了三维空间各点的回弹值。结合试验结果,对影响回弹的因素进行了分析讨论。试验结果表明:回弹随着压边力增大而减小;在一次成形中,试件弯曲的点数影响回弹角的大小。 相似文献
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工艺切口在控制板料冲压变形趋势中的应用 总被引:5,自引:0,他引:5
分析了在冲压成形过程中工艺切口和工艺孔对板料应力、应变状态的影响。讨论了和工艺切口改变板料变形趋势的方法,以及在冲制工艺切口时应当注意的问题。 相似文献
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轿车车身覆盖件在冲压生产中产生的拉毛问题,主要是板料与模具在相对滑动摩擦过程中产生犁削效应和粘着效应作用的结果.冲压生产中的拉毛不可避免,但可以从保证冲压模具和板料的清洁度、选用优良的模具材质、尽量提高模具工作表面的硬度和降低表面粗糙度、进行合适的润滑、提高模具调试维修状态等方面对拉毛问题进行改善;保证冲压钢板表面具有... 相似文献
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采用DYNAFORM软件对某汽车顶盖进行了有限元分析,研究了摩擦因数、模具间隙、材料参数等因素对该零件成型的影响.结果表明,凹模与板料之间的摩擦因数对该汽车顶盖的成型影响最大:凸模与板料之间的摩擦因数对该零件变形均匀性影响最大,改善凸模与板料之间的润滑条件可以显著提高顶盖的变形均匀性:应变硬化指数n对该零件成型的安全裕... 相似文献
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载货车底盘件一般使用热轧板在模具上冲压成形,有时还采用双层板同时成形。由于板料强度高且较厚,应用传统模具成形时,模具承受载荷较大,板料与凹模之间发生剧烈摩擦。这种摩擦不仅削弱凹模镶块的寿命,同时会拉伤成形件的表面,形成拉痕。本文分析了该拉痕产生的机理和影响因素,重点研究了减轻拉痕的措施,给出了适合现生产的解决措施。 相似文献
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通过对国产08A1钢板四种试样的成型试验,研究了成型时板料向凹模的流入量与技术参数之间的关系。其中板料的应力应变状态,轧制方向,厚度和坯料尺寸等因素都影响成型时板料内的流入量。增大压边力,将减少板料向凹模内的流入量。 相似文献
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Zhiyong Shi Lirong Guo Zaigang Chen Rui Zhang Kaikai Lv 《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2017,55(9):1368-1383
The heavy haul coupler/buffer system equipped with arc surfaces on the coupler tail and the follower is widely applied to connect the locomotives and wagons. As one of the most important parameters, arc surfaces friction coefficient plays a key role in coupler instability, which threatens the safety of trains. To investigate the effect of arc surfaces friction coefficient on coupler stability, a simulation model adopting the latest modelling methods is established and field tests employing the locomotives equipped with different friction coefficients are conducted. The results show that the friction coefficient of arc surfaces can affect the coupler yaw angle remarkably. Increasing the friction coefficient can improve the coupler stability. However, under severe compressive force condition, the increased friction coefficient can be reduced quickly, which calls for further attention. 相似文献
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通过对某轻型客车矩形截面梁骨架式白车身和薄板冲压件骨架式白车身两种结构进行有限元对比分析,掌握了两种白车身的结构性能;并对其中的薄板冲压件骨架式白车身进行有限元优化,在保证车身性能的情况下,轻量化程度达到12.7%。 相似文献
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本文采用的模拟板材沿凸模圆角拉延过程的拉伸试验方法,对汽车用热浸镀锌钢板的摩擦特性进行了系统试验研究,建立了镀锌层表面粗糙度,润滑状况,模具圆角半径与热浸镀锌钢板摩擦特征参数之间的关系。结果表明,镀锌层表面粗糙度对板材的摩擦特性影响很小,采用油性润滑剂比水溶性润滑剂能更好地改善镀锌钢板与模具之间的摩擦状况。 相似文献
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《Vehicle System Dynamics: International Journal of Vehicle Mechanics and Mobility》2012,50(9):1324-1341
To investigate the stability mechanism of a type of heavy-haul coupler with arc surface contact, the force states of coupler were analysed at different yaw angles according to the friction circle theory and the structural characteristics of this coupler were summarised. A multi-body dynamics model with four heavy-haul locomotives and three detailed couplers was established to simulate the process of emergency braking. In addition, the coupler yaw instability was tested in order to investigate the effect of relevant parameters on the coupler stability. The results show that this coupler exhibits the self-stabilisation and less lateral force at a small yaw angle. The yaw angle of force line is less than the actual coupler yaw angle which reduces the lateral force and the critical instability. An increase in the friction coefficient of the arc contact surfaces can improve the stability of couplers. The friction coefficient needs to be increased with the increase in the maximum coupler longitudinal compressive force. The stability of couplers is significantly enhanced by increasing the secondary suspension stiffness and reducing the clearance of the lateral stopper of the locomotives. When the maximum coupler compressive force reaches 2500 kN, the required friction coefficient reduces from 0.6 to 0.35, which notably lowers the derailment risk caused by the coupler. The critical instability angle of the coupler mainly depends on the arc contact friction coefficient. When the friction coefficient is 0.3, the critical instability angle was 4–4.5°. The simulation results are consistent with the locomotive line tests. These studies establish meaningful improvements for the stability of couplers and match the heavy-haul locomotive with its suspension parameters. 相似文献