共查询到20条相似文献,搜索用时 117 毫秒
1.
简要介绍冷/温锻复合成形技术的特点和应用范围,并对冷/温锻复合成形工艺中的温锻的成形温度、坯料的加热方法和时间、温锻模具的冷却与润滑、温锻预制坯的软化处理和表面润滑处理等作了详细的阐述。然后列举了两个已经大批量生产的工程实例,详细说明冷/温锻复合成形技术的成形工艺过程。实践表明,冷/温锻造复合成形技术不仅可以生产重达几十公斤、几何形状复杂、精度要求极高而难以用冷锻或温锻加工方法制造的零件,而且经济效益十分明显。 相似文献
2.
3.
4.
5.
6.
7.
张猛 《机械工人(热加工)》2002,(4)
二、直齿锥齿轮锻造生产线设备选型 直齿锥齿轮锻造生产过程包括:预制坯制备、温(热)锻加热或冷锻前的退火软化、锻造成形及后处理等。所用设备类型根据工艺要求确定。 1.制备预制坯的设备选型 温锻成形温锻精整(两火两锻)、热锻成形温锻精整(一火两锻)及温锻成形冷锻精整工艺都是开式模锻造,锻造直齿锥齿轮的预制坯都是圆柱 相似文献
8.
回弹和变形是影响高强度装载机覆盖件冲压成形形状精度的主要因素,通过22MnB5合金板热冲压成形实验,考察了热冲压成形的传热特征,推导出的热冲压成形传热数学模型的基本方程,提出热冲压成形模具冷却系统设计相关技术问题.研究表明,当冷却速度达到或超过临界冷却速度,才能使奥氏体直接转变为均匀马氏体;在模具结构、冷却系统、冷却介质等因素确定的情况下,冷却速度只与板材自身条件有关,可以通过控制最佳水流速度实现对最佳冷却速度的控制,达到减少和消除热冲压成形中变形和回弹等缺陷,提高装载机覆盖件热冲压成形质量. 相似文献
9.
针对淬火过程中热冲压件B柱结构复杂位置处冷却速率小,在组织转变过程中未能完全转变为马氏体组织,影响其力学性能的问题,进行了热冲压成形工艺研究。提出了优化模具冷却水管道布置以增大局部模具对板料冷却速率和优化模面形状以减小板料与模具间隙的两种优化设计,进行了数值模拟及对试验结果进行整理,研究了热冲压成形工艺中的重要参数冷却速率。结果表明:优化模具冷却水管道布置的设计对热冲压件B柱形状复杂处的冷却速率有一定的提高作用,优化模面形状的设计显著地提高了B柱结构复杂处的冷却速率,同时表明模具与板料间隙的存在对板料冷却速率有很大的影响。 相似文献
10.
注塑模具的冷却系统对注塑件的成型质量和产品的生产效率有很大影响。重点讨论了影响注塑模具冷却的因素,以及注塑模具冷却系统设计的原则。然后对风扇叶注塑模具冷却回路进行了简略计算。并根据风扇叶的整体结构,对其模具提出了三种冷却回路布置方案。最后基于模流分析软件,运用MPI/Cool模块对不同的冷却系统进行冷却分析,通过对冷却分析的结果进行对比得到相对较优的冷却回路。最终获得良好的冷却效果,达到提高产品质量、缩短成形周期、提高生产率等目的。 相似文献
11.
基于Simufact.Forming径向锻造模块对某叶片毛坯锻造成形过程进行数值模拟分析,研究了径向锻坯到叶片模锻的成型过程,获得了叶片锻坯在径向锻造过程中等效应变以及锻流线分布规律。深入分析锻坯锻透性,并对径锻成形过程进行理论计算和试验验证。结果表明:适当提高相对压下率能使锻坯变形均匀,采用拉打径向锻造方式能够有效保证锻坯成型的尺寸精度,得到的叶片锻坯模锻充型效果较好,飞边分布均匀,锻坯心部等效应力在锻打时有规律地发生波动,旋转锻打使金属材料沿周向流动,锻流线的扭转角与旋转角相一致,锻坯质量较好,无明显缺陷。 相似文献
12.
13.
14.
为了研究离心熔铸反射镜制造技术中热历史状态(成型温度及冷却速度)对成型效果的影响,采用有限元分析软件Abaqus对不同的成型温度及冷却速率进行仿真分析,确定成型温度为950℃、冷却速率为1℃/s时可以完成反射镜在模具中的充模和成型;之后进行离心熔铸试验并对成型结果进行测量。在冷却速度大于1℃/s时,反射镜由于冷却后局部残余应力过大,导致其发生碎裂。同时通过对仿真结果、理论计算结果以及试验结果的分析对比,得到反射镜边缘的轴向高度与理论值相差10.12 mm,具有较大的面型误差,产生面型误差的原因是由于在高温成型冷却后反射镜体积收缩导致面型发生变化。 相似文献
15.
16.
《Journal of Mechanical Working Technology》1987,14(2):121-135
Multistage cold or warm forging is being used increasingly to produce axisymmetric parts as energy and material prices continue to increase. One of the major efforts required in applying this process successfully is the design of the forming sequences for multistage forging machines. This work is done by highly experienced die designers and it requires both experienced judgment and the application of established design rules. This design task is reasoning-intensive rather than computation-intensive; thus, it is very suitable for the application of expert-systems methodology. This paper describes the development of a prototype expert system for forming-sequence design in cold and warm forging of axisymmetric parts. 相似文献
17.
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
18.
19.
Menghan Wang Dong Xiang Chuan Xiao Jie Zhou Zhi Jia 《The International Journal of Advanced Manufacturing Technology》2012,59(5-8):473-482
In this paper, a thermal–mechanical coupled simulation model for two-roll cross wedge rolling (CWR) was developed to investigate the influence of cooling condition of tools on central deformation of workpiece and tool wear by using three-dimensional rigid-plastic finite element method. Based on the simulation results, the information about central deformation of workpiece and tool wear with and without tool cooling was compared and analyzed. The study results indicate that forging quality and tool life can be improved by means of cooling the tools with cooling water. Subsequently, an industrial example of CWR in blank forming for engine connecting rod was presented to verify the feasibility of study results. In this industrial application, higher forging quality and longer tool life were obtained, which benefits the decrease of production cost. This study provides insights into the mechanisms of central deformation of workpiece and tool wear under different cooling conditions of tools in CWR process as well. 相似文献