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1.
环件轧制孔型共轭设计   总被引:2,自引:0,他引:2  
本文分析了环件轧制的啮合运动,基于啮合理论提出了环件轧制孔型的共轭设计方法,应用方法,设计了典型环件的轧制孔型,因而从理论上解决了复杂环件轧制孔的设计难题。  相似文献   

2.
冲压无法兰边浅盒制件时,挖去多余材料有利于制件成形。介绍了材料变形分析和毛坯的设计方法。  相似文献   

3.
陈学胜 《汽车工程》1993,15(2):113-121
用环轧取代汽车齿轮的传统模锻制坯工艺从经济效益到锻件质量都有极大的优越性,但获其工艺参数尚有困难。本文根据上限原理用内力平衡分析法求得了主辊轧制力合力、作用点、方向及轧制力矩等主要环轧工艺参数,为其设备、工艺的设计提供了理论依据。分析表明,环件组织质量取决于相对接触长度p,与芯辊辊径密切相关;p值的合理范围为0.3~0.7;主辊接触处当量摩擦系数与接触表面无关。  相似文献   

4.
环件轧制中的形状和精度   总被引:4,自引:0,他引:4  
从几何学和运动学方面研究了环件轧制中形状变化规律导出了环件内外轮廓曲线方程和内外轮廓椭圆度计算式,分析了环件轧制中椭圆变化规律和影响因素,进行了环件轧制试验,试验结果与理论计算是一致的。  相似文献   

5.
结合等效拉延筋的毛坯设计方法的研究   总被引:1,自引:0,他引:1  
研究了在板料成形毛坯设计中加入等效拉延筋进行计算的毛坯设计方法,提出了利用反向方法结合等效拉延筋进行毛坯设计的设计思想。通过实例的研究表明,这种毛坯设计方法是合理的,同时也表明结合等效拉延筋的毛坯设计方法可以用于大型覆盖件的毛坯设计。  相似文献   

6.
分析了EQ140型汽车差速器从动齿轮锻件辗扩变形特点和辗扩用毛坯设计中的主要问题,阐明了辗扩用毛坯优选法设计的原理和计算过程,应用优选法指导EQ140型汽车差速器从动齿轮扩工艺试验,可使试验次数大为减少。  相似文献   

7.
浅拉深小曲率汽车覆盖件冲压成形质量控制   总被引:2,自引:0,他引:2  
浅拉深小曲率汽车覆盖件冲压成形与深拉深覆盖件相比具有不同的变形特点,其主要质量问题是塑性变形小,导致冲压件成形后形状冻结性差、刚性不足,以及用这类零件作为外板零件时容易产生形状精度不高等。对此,必须进行变形特点分析,采取多方面的措施,通过增加毛坯的塑性变形来有效地提高浅拉深小曲率覆盖件的刚度,从而得到高质量的冲压件。  相似文献   

8.
轻型车减振器支架冲压成形的数值分析及工艺开发   总被引:2,自引:0,他引:2  
本文利用LS-DYNA3D软件包对轻型车减振器支架的冲压成形过程进行了数值分析,揭示了曲面压料面下的毛坯成形过程中金属流动规律及变形特点,并对该类件成表中出现的破坏和起皱的主要原因进行了研究,通过模拟工艺调试过程开发了新的成形工艺,使零件的废品率和次品率分别由15%降到0.05%以下。为同类件的冲压工艺的编制和模具设计提供了理论依据。  相似文献   

9.
月形修正法     
翻边是板料冷冲压的基本工序之一,本文讨论了翻边系指压缩类圆角翻边,以矩形件为例,对矩形件角部翻边落料毛坯尺寸的计算提出了一种新的方法--月形修正法。该方法适合汽车异形件的角部翻边毛坯计算,翻边后无需修边处理。  相似文献   

10.
汽车覆盖件的拉伸毛坯,传统的做法是拉伸前称落料。而IVECO(依维柯)车身覆盖件大多采用方块坯料直接拉伸,这对缩短模具制造周期,节约生产成本,具有实际意义。本文介绍了IVECO车身覆盖件坯料设计的几种方法。  相似文献   

11.
利用楔型横轧加工工艺对2A12高强度铝合金连杆的台阶轴类毛坯进行了成型加工。对原始坯料形状的选择、坯料加热温度规范的制定、变形工步的设置、润滑剂及润滑方式的选择及楔型模楔型部分的设计等进行了介绍。与自由锻、辊锻等成型加工方法相比,楔型横轧工艺不仅能够显著提高生产效率和材料利用率,而且能够保证铝合金台阶轴毛坯的尺寸一致性,保证了后续模锻成型的锻件质量,解决了因台阶轴形状尺寸一致性差所引起的后续模锻成型锻件存在充不满和折叠等缺陷问题。  相似文献   

12.
基于汽车轻量化用材,介绍了一种显著减轻车身质量的新型薄板--连续变截面辊轧板(TRB).与激光拼焊板相比,TRB在减重效果、机械性能、适应性、厚度优化分布、断面曲线多样化、后续加工可靠性等方面有着明显的优势.讨论了TRB在车身制造中需要解决的覆盖件模具设计、冲压成形过程中的变形、材料流动性和板料回弹等关键问题.  相似文献   

13.
辗扩工艺生产汽车后桥从动锥齿轮锻坯的应用实践   总被引:2,自引:0,他引:2  
张猛 《汽车工程》1994,16(2):111-115,128
本文根据辗扩成形汽车后桥从动锥齿轮坯铅试件的网格试验所揭示的变形区微单元应变状态,论述了这种阶梯孔环形件辗扩变形的特征;设计了辗扩用孔型及预制坯;进行了力能校核的实例计算;阐述了辗扩工艺生产汽车后桥从动锥齿轮锻坯的应用情况,并与模锻工艺生产该件的经济技术指标进行了比较。  相似文献   

14.
One of the most important maintenance costs in tramway transport comes from wear of wheel profiles. In the highly competitive railway market, the prediction of wear is then a major concern of the constructors. In this article, we present and compare four models well adapted to tramway conditions, involving contacts on the rolling tread and on the flange with very different sliding and pressure conditions. Moreover, all models can be implemented from the natural outputs of the railway simulation packages classically used in industry for the dynamics design of the vehicles. The first one, proposed by Jendel, is based on the well-known Archard's wear model. Enblom continues Jendel's approach by taking into account the contribution of wheel deformation on the sliding velocity. The last two models, developed by Zobory, and Pearce and Sherratt, determine the wear from the energy dissipation in the contact area. The models are first compared on a theoretical basis and, for that purpose, are rewritten in a common form. Two cases are distinguished: mild wear as arising on the rolling tread and severe wear as arising on the flange. The models are also compared in the practical case of an urban transport vehicle running on circular tracks with different curve radii. Although the models show equivalent trends according to the theoretical study, important discrepancies appear between estimated wear depths. All models are actually dependent on experimental coefficients and it is likely that they were estimated in different conditions. On the other hand, a reasonable agreement can be found in some particular conditions. As an example, Zobory's, Enblom's and Jendel's models are very close to each other in severe wear conditions. This work shows that a general and reliable model could probably be developed from all positive aspects of the existing ones.  相似文献   

15.
One of the most important maintenance costs in tramway transport comes from wear of wheel profiles. In the highly competitive railway market, the prediction of wear is then a major concern of the constructors. In this article, we present and compare four models well adapted to tramway conditions, involving contacts on the rolling tread and on the flange with very different sliding and pressure conditions. Moreover, all models can be implemented from the natural outputs of the railway simulation packages classically used in industry for the dynamics design of the vehicles. The first one, proposed by Jendel, is based on the well-known Archard's wear model. Enblom continues Jendel's approach by taking into account the contribution of wheel deformation on the sliding velocity. The last two models, developed by Zobory, and Pearce and Sherratt, determine the wear from the energy dissipation in the contact area. The models are first compared on a theoretical basis and, for that purpose, are rewritten in a common form. Two cases are distinguished: mild wear as arising on the rolling tread and severe wear as arising on the flange. The models are also compared in the practical case of an urban transport vehicle running on circular tracks with different curve radii. Although the models show equivalent trends according to the theoretical study, important discrepancies appear between estimated wear depths. All models are actually dependent on experimental coefficients and it is likely that they were estimated in different conditions. On the other hand, a reasonable agreement can be found in some particular conditions. As an example, Zobory's, Enblom's and Jendel's models are very close to each other in severe wear conditions. This work shows that a general and reliable model could probably be developed from all positive aspects of the existing ones.  相似文献   

16.
以G109线改扩建工程中跨高速公路桥为工程实例,对新型管翼缘组合梁桥的受力及关键技术进行分析。归纳出新型管翼缘组合梁桥若干设计特点,开拓此类桥梁的设计思路,为管翼缘组合桥梁设计提供了研究参考。  相似文献   

17.
宋远  李兆平  黄明利  张志恩 《隧道建设》2020,40(Z1):216-224
为进一步探讨隧道波纹钢套衬结构纵向连接接头的安全性和适用性问题,对不同型号拼装式波纹钢板纵向接头抗弯力学性能进行研究,选取200 mm×55 mm、300 mm×110 mm和400 mm×150 mm 3种型号波纹钢板试件进行接头抗弯数值模拟。共设计12种工况,对比不同规格螺栓的应力分布规律、变形破坏形式及不同螺栓预紧力条件下的法兰板极限承载力及变形破坏特征,就螺栓应力、跨中挠度、极限承载力、法兰板接缝张开量及塑性破坏等方面进行深入分析。研究结果表明: 1)螺栓主要受拉弯变形,内侧螺栓较外侧螺栓受力更大,率先达到屈服状态; 2)接头薄弱点主要在于法兰板,其更容易发生变形破坏; 3)螺栓预紧力对波纹钢板的极限承载力、跨中挠度及接缝张开量均有一定的影响; 4)大波形波纹钢板极限抗弯承载能力约为深波形和中波形的1.36倍和1.67倍。  相似文献   

18.
为探究波纹钢板综合管廊在低周循环往复荷载作用下的滞回性能,以某波纹钢板综合管廊实际工程为依托,采用数值模拟与试验相结合的方法,研究管廊在横向、纵向、竖向共6种荷载工况下的抗震性能,以及法兰连接、法兰厚度、管廊壁厚(波纹钢板厚度)、螺栓位置等参数对结构滞回性能的影响。研究结果表明: 1)在低周循环往复荷载作用下,波纹钢板综合管廊塑性变形能力强,抗震性能良好;但管片拼装节点处是其薄弱位置,易发生脱开现象。 2)法兰对结构力学性能及滞回性能的影响显著,但法兰厚度改变对其影响较小。 3)环向法兰上螺栓的位置对结构纵向滞回性能影响较大,对其他方向滞回性能则几乎无影响。 4)波纹钢板厚度是影响结构抗震性能的关键因素。  相似文献   

19.
汽车半轴凸缘是受弯扭联合作用的联接零件,其强度,载荷及实际尺寸具有不确定性,中运用模糊可靠性设计理论,在隶属函数和基本随机变量概率特性已知的情况下,导出了汽车半轴凸缘的模糊可靠性设计公式,并给出了计算实例,应用模糊可靠性设计理论,可以提高设计水平,节省材料,降低成本,符合汽车轻量化的发展方向。  相似文献   

20.
制备了直接离子渗氮环与超声滚压加工-离子渗氮环两类摩擦学试样。利用电子显微镜、硬度计、X射线衍射仪和能谱仪,对表面改性层进行了表征,分析了超声滚压预处理对316L不锈钢活塞环离子渗氮行为的影响;在润滑油条件下,使用往复式摩擦磨损试验机,对比考察了直接渗氮环和超声滚压-渗氮环的摩擦学性能。结果表明,超声滚压-渗氮环相对于直接渗氮环渗氮层的氮含量增加了2.9倍,显微硬度提高了1.1倍,摩擦因数降低了0.04,耐磨性提高了2.8倍。发动机台架试验表明,超声滚压-渗氮环与硼铸铁氮化气缸套的匹配性最好。  相似文献   

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