共查询到20条相似文献,搜索用时 218 毫秒
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大型船用曲轴TR法镦锻成形缺陷分析与工艺优化 总被引:1,自引:0,他引:1
大型曲轴是大型内燃机的关键零件。针对我国大型船用曲轴锻造中存在的精度低、加工余量大等问题,采用DEFORM-3D软件对其TR镦锻过程进行了数值模拟仿真。通过模拟分析曲轴成形的塑性流动规律,找出了大型船用曲轴曲拐成形过程中的典型缺陷连杆颈和曲柄臂外侧折叠的成因。研究发现,弯曲下模和预锻模设计不合理是造成曲轴锻件折叠缺陷的主要原因;并在此基础上优化了锻件成形的工艺方案,从而为大型曲轴镦锻模具设计提供了科学依据。生产试验表明,采用新的模具结构设计方案,可以有效避免大型曲轴镦锻时的折叠缺陷,所成形的曲轴质量良好。 相似文献
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大型全纤维曲轴平衡块成形塌角问题研究 总被引:1,自引:0,他引:1
针对曲轴锻造平衡块塌角问题,从加热、工艺、模具等不同的角度分析了锻造过程中可能出现缺陷的原因,阐述了NTR法的锻造工艺特点和相应的解决措施,并简单介绍了德国的“CATEAR”镦锻模具。通过实际生产验证了NTR法锻造的可行性和优越性,为全纤维曲轴的锻造提供了新的理论依据和实际经验。 相似文献
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优化了板体的锻造工艺,将锻造工艺中的平面镦粗去氧化皮工步优化为成形镦粗,将原镦粗的扁平形状改为中间低两边高的形状,以达到更合理的材料分配。通过优化成形镦粗的形状和高度,将终锻模具的最大等效应力降低了30%左右,终锻模具易磨损位置的磨损量降低了25%左右,达到了提高终锻模具寿命的目的。同时,优化了顶杆的安装位置,在顶杆位置处增加余料仓,增加材料的流动空间,降低顶杆受力,可以有效提高顶杆寿命。试验发现,成形镦粗件的长度对终锻成形的影响不容忽视,成形镦粗件长度应小于锻件长度,否则容易产生折叠缺陷。将试生产锻件与模拟结果对比,可以确认优化后的成形镦粗工步和顶杆余料仓的作用是有效的。 相似文献
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以微车内燃机用曲轴的成形工艺开发为目的,分析了该规格曲轴成形可行性及工艺难点,设计了预、终锻件形状及预、终锻模具结构.在预锻件平衡块的内侧设计了厚度为15mm的工艺连皮,预、终锻模具设置了阻力墙结构,上述两项工艺改进有效的保证了终锻件的成形效果.利用金属塑性成形仿真软件DE-FORM-3D,对改进的工艺进行仿真分析,仿真结果有效的验证了工艺方案.模拟预测了预、终锻成形力分别为39.9MN,终锻为56MN.设备63MN有富余.模拟显示终锻件的平衡块顶端完全充满.基于模拟验证的工艺和设计的模具进行生产试制,经检测曲轴锻件产品的尺寸及性能完全达到了设计要求. 相似文献
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针对十字轴热模锻成形过程中飞边大、成形力大的问题,根据十字轴形状尺寸及锻造成形工艺特点,提出十字轴小飞边精密成形工艺。采用Deform-3D对十字轴小飞边精密成形工艺过程进行数值模拟,对模拟成形的十字轴锻件及其金属速度场、等效应变、模具载荷-时间曲线进行分析。模拟结果显示,十字轴锻件成形完整,金属流动均匀,模具载荷减小。结合模拟结果,设计制造模具进行十字轴成形工艺试验。试验得到的十字轴锻件,填充饱满,无折叠、表面裂纹等缺陷,飞边明显减小,与模拟结果一致。结果表明:改变十字轴热模锻成形工艺,采用十字轴小飞边精密成形工艺,使锻件飞边减小,锻造过程成形载荷降低。 相似文献
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机匣体多向模锻的热力耦合数值模拟 总被引:2,自引:0,他引:2
机匣体是枪械上的一个关键零件,其质量对枪械的整体性能有着非常重要的影响.机匣体的材料为LC4超硬铝合金,该合金的塑性差,变形流动阻力大,且具有速度敏感性.对机匣体锻件的结构特点及相对尺寸关系进行了分析,指出多向模锻是成形该锻件的优选工艺方案.制定了多向模锻工艺方案,设计了辊锻毛坯和多向模锻模具,并采用DEFORM-3D对终锻成形过程进行了数值模拟,分析了变形过程及温度场的变化规律.根据模拟结果进行了工艺试验,最后得到了合格的样件.证明了采用该工艺方案可以很好地保证成形温度,提高材料塑性,解决其成形困难的问题,同时也证明数值模拟的正确性. 相似文献
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Deformation characteristic of the precision forging of a blade with a damper platform using 3D FEM analysis 总被引:5,自引:0,他引:5
A blade with a damper platform is one of the most important types of blades being developed in aeronautical engines. However, this type of blade is complicated in shape, consisting of four feature parts with different geometrical shapes. Besides obvious flow of material along the transverse direction, there is material flow along the longitudinal body during its forging process. In addition, the material used is difficult to deform. All these have a significant influence on the precision forging process of the blade. Thus, it is necessary to choose some feature sections along the transverse and longitudinal direction of blade and systematically understand the deformation characteristics of blade forging process. In this paper, by means of 3D rigid–viscoplastic FEM simulation of the precision forging process of the blade, the deformed meshes, distributions of some field variables, including velocity, effective strain, effective strain rate and effective stress are presented for the four chosen feature cross-sections and the velocity fields are obtained for a selected typical longitudinal feature section, and further the deformation characteristics of forging this blade have been revealed. This research may serve as a guide to the optimization design of the relevant processes and dies. 相似文献
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某产品上用的一重要零件为薄壁曲面类零件,实际生产中主要采用机械加工制作,工序多,时间长,并浪费原材料.本文采用锻造成形工艺,锻模设计为曲面分模面模具结构,实现了薄壁曲面零件的锻造成形.零件成形后,无需再进行后续机械加工,产品的尺寸和形状均可直接达到使用要求.经过工艺试验和小批量的试生产考核,其尺寸和形状均能满足图纸技术要求,并且产品尺寸和形状的一致性好.与机械加工工艺相比,锻造成形工艺大幅度提高了产品生产效率和材料利用率,极大降低了生产成本. 相似文献
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本文采用三维刚塑性有限元法对圆盘件的摆动辗压过程进行了数值模拟,针对具体算例进行了圆盘件摆辗中心变薄缺陷的预测,并且对所提出的缺陷防止办法进行了数值模拟,结果说明,采用有限元方法进行圆盘件摆动辗压工艺缺陷预报是可行的,所提出的工艺优化方案改善了工件的受力条件,避免了工件中心变薄的发生。 相似文献
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Lü Cheng ZH ANG Li-wen .State Key Laboratory for Materials Modification by Later Ion Electron Beams Dalian University of Technology Dalian China .School of Materials Science Engineering Dalian University of Technology Dalian China 《中国有色金属学会会刊》2006,16(6):1386-1390
1Introduction The TC4alloy mounting part is an important part of aeronautic engine.Currently,these mounting parts are mainly manufactured by metal cutting,which is expensive and requires a lot of manufacturing time.Furthermore,in this way the forging flow… 相似文献
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Beom-Soo Kang Shiro Kobayashi 《International Journal of Machine Tools and Manufacture》1994,34(8):1133-1146
A systematic approach to process sequence design is established by the finite element method for multi-operational cold forging to form a constant velocity joint housing. Both the loading simulation and the backward tracing by the rigid plastic finite element method provide useful information for designing new process sequences. The newly designed sequence has four forming operations and one annealing treatment, and can achieve net-shape manufacturing, while the conventional process sequence has five forming operations and two annealing treatments, and requires machining after forming. The refinement at the top surface of the product is made by applying the backward tracing scheme for the purpose of net-shape manufacturing. This specific case can be considered for application of the method and for development of the sequence design methodology in general. 相似文献