某商用车车架结构设计及强度分析和试验研究
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摘要
汽车的车架是汽车承受各种载荷的关键总成之一,其设计的合理与否直接关系到整车设计的成败。如何设计合理的车架已经成为现代汽车设计的重要内容之一。本文结合实际工程经验,探讨载商用车车架设计方法,积累车架强度校核经验,获得一些有益的结论,从而促进整车设计水平的提高。
本文以某商用车车架为研究目标,研究了车架总成外廓尺寸确定方法,详细分析各因素对纵梁抗弯能力的影响,通过对比分析,最终确定纵梁的各项设计参数,本文简述了横梁的设计过程,并对复杂形状横梁进行成型工艺分析,本文还研究了车架总成有限元分析和模态试验过程,而且对道路试验损坏件进行了失效分析,提出了解决方案。
Frame is a main load bearing component of the truck. Based on longitudinal beam characters, the frame can be divided into the ladder type frame, X-type frame, and backbone type frame. The load bearing mechanism of the frame is extremely sophisticated. At standstill, supported by the suspension system, the frame bears the load and gravity of all the components of the truck; and when the truck is running, due to the action of load, and mass and working load (e.g. driving power, braking force and steering force) of all the components of the truck, the frame will have to endure randomly variable dynamic load from different directions and to different degrees. The bend, eccentric twisting and overall twisting may occur to the frame under action of various loads.
In the previous design practice of Commercial Vehicle frame, the traditional experience is frequently adopted. The sectional dimensions of longitudinal beam and structural form of cross beam are monotonous, the distribution of cross beam is too simple, and the gross weight of the frame is heavier, and therefore, stress concentration may easily occur on local area.
For modern cars, requirements for riding comfort, lightweight and high speed design, structural strength of the frame, bend and torsional vibration generated at external excitation, and gross weight based on cost effect and oil consumption have become increasingly higher, and been subdivided. With rapid development of the automobile industry, requirements for car performance are getting higher and higher so that the traditional design and calculation method can no longer meet the requirements for design of modern car. Emergence of the electronic computer and rapid development of the finite element method have brought a new revolution for calculation and analysis of the structural performance of the frame. The finite element method is used to conduct the performance analysis for the frame structure, and the structural optimization of the frame is taken into consideration in the design, which is of great significance for improving all the performances of the whole car, reducing the design and manufacturing cost, and increasing the market competitive power.
The author of this thesis has designed a complete process workflow in combination with these requirements: Starting from the market and input to the whole vehicle, it determines the overall sizes, material and other parameters of the frame, then, it determines the structural dimensions of the longitudinal beam and cross beam, respectively. Upon completion of strength and forming process analysis, and subdivision of the frame assy. 3D drawings, it makes the finite element checking and analysis for the frame assy. Upon completion of the trial assembly of the frame assy., it makes the modal test, and analyzes and solves the issues found during the test.
This thesis has the following achievements:
New material and manufacturing technology are adopted. The new high strength steel plate is adopted, which can improve the yield strength utmost limit of the material itself, and greatly improves the load bearing capacity without increasing the dimensions.
New design and calculation method and strict design procedure are adopted. The finite element method for calculation of the frame is popularized in all aspects. Based on the finite element calculation for static bending of the frame, before completion of the product engineering drawings, the finite element calculation for the whole frame is conducted at first. The previous practice, i.e. completion of product engineering drawing before the finite element checking calculation, is changed. The deepgoing customer investigation is conducted to know the actual application conditions of Chinese users so as to get rid of blind copying, and presents its own product features.
Standard holes are adopted on the web of the longitudinal beam of the frame, which can cut down the types of the cross beam of the frame, simplify the stamping process of the longitudinal beam and assure the universal use of other assemblies and parts on trucks within the same series or cross-series. Further, it can reduce the work quantity for layout on the modified truck and facilitate refitting. Therefore, the refitting factory does not need to make additional drilling when refitting, which can protect the paint finish. It can also optimize the piping and wiring, improve the appearance, and facilitate refitting operation.
When the developed width of the longitudinal beam is set, and when the ratio between the height of the web plate and the developed width of the longitudinal beam is equal to 0.75, its resistance to bend is the utmost.
Both upper and lower wing faces of the longitudinal beam should be equal. If there are the upper and lower reinforcement plates, then, the sizes of the upper and lower reinforcement plates should be same.
To improve the resistance to bend of the channel section beam, adhesion of reinforcement plate to the wing face will present better effect than apply it on the web plate. To raise the height of the wing face will produce obvious action to the resistance to bend of the channel section beam.
Drilling on the web plate, especially drilling on area near the neutral shaft, will produce much lesser influence on the bend resisting area factors than drilling on the wing face, and in consideration of the influence of holes on the wing face to the stress concentration, the important conclusion can be made that in principle, no drilling shall be made on the wing face of the channel longitudinal beam of the frame.
For cross beam of complicated forms, the forming process can be analyzed at first so that preliminary judgment can be made to process performance of the cross beam without waiting for completion of the trial manufacturing dies. In such a way, the part forms can be regulated in time so that not only the development time can be saved, but also the waste of tooling dies can be avoided.
Sometimes, the failure cause of parts cannot be concluded via experience. Therefore, the finite element analysis and other methods shall be used to assist the judgment. Most of the strength failure need reinforcement means, however, the increased rigidity is not necessarily a good solution. Instead, the force bearing conditions and deformation tendency should be analyzed according to the position and surrounding environment of the part (structural rigidity and force bearing status) so as to reasonably determine the structural rigidity and strength of the parts designed.
本文以某商用车车架为研究目标,研究了车架总成外廓尺寸确定方法,详细分析各因素对纵梁抗弯能力的影响,通过对比分析,最终确定纵梁的各项设计参数,本文简述了横梁的设计过程,并对复杂形状横梁进行成型工艺分析,本文还研究了车架总成有限元分析和模态试验过程,而且对道路试验损坏件进行了失效分析,提出了解决方案。
Frame is a main load bearing component of the truck. Based on longitudinal beam characters, the frame can be divided into the ladder type frame, X-type frame, and backbone type frame. The load bearing mechanism of the frame is extremely sophisticated. At standstill, supported by the suspension system, the frame bears the load and gravity of all the components of the truck; and when the truck is running, due to the action of load, and mass and working load (e.g. driving power, braking force and steering force) of all the components of the truck, the frame will have to endure randomly variable dynamic load from different directions and to different degrees. The bend, eccentric twisting and overall twisting may occur to the frame under action of various loads.
In the previous design practice of Commercial Vehicle frame, the traditional experience is frequently adopted. The sectional dimensions of longitudinal beam and structural form of cross beam are monotonous, the distribution of cross beam is too simple, and the gross weight of the frame is heavier, and therefore, stress concentration may easily occur on local area.
For modern cars, requirements for riding comfort, lightweight and high speed design, structural strength of the frame, bend and torsional vibration generated at external excitation, and gross weight based on cost effect and oil consumption have become increasingly higher, and been subdivided. With rapid development of the automobile industry, requirements for car performance are getting higher and higher so that the traditional design and calculation method can no longer meet the requirements for design of modern car. Emergence of the electronic computer and rapid development of the finite element method have brought a new revolution for calculation and analysis of the structural performance of the frame. The finite element method is used to conduct the performance analysis for the frame structure, and the structural optimization of the frame is taken into consideration in the design, which is of great significance for improving all the performances of the whole car, reducing the design and manufacturing cost, and increasing the market competitive power.
The author of this thesis has designed a complete process workflow in combination with these requirements: Starting from the market and input to the whole vehicle, it determines the overall sizes, material and other parameters of the frame, then, it determines the structural dimensions of the longitudinal beam and cross beam, respectively. Upon completion of strength and forming process analysis, and subdivision of the frame assy. 3D drawings, it makes the finite element checking and analysis for the frame assy. Upon completion of the trial assembly of the frame assy., it makes the modal test, and analyzes and solves the issues found during the test.
This thesis has the following achievements:
New material and manufacturing technology are adopted. The new high strength steel plate is adopted, which can improve the yield strength utmost limit of the material itself, and greatly improves the load bearing capacity without increasing the dimensions.
New design and calculation method and strict design procedure are adopted. The finite element method for calculation of the frame is popularized in all aspects. Based on the finite element calculation for static bending of the frame, before completion of the product engineering drawings, the finite element calculation for the whole frame is conducted at first. The previous practice, i.e. completion of product engineering drawing before the finite element checking calculation, is changed. The deepgoing customer investigation is conducted to know the actual application conditions of Chinese users so as to get rid of blind copying, and presents its own product features.
Standard holes are adopted on the web of the longitudinal beam of the frame, which can cut down the types of the cross beam of the frame, simplify the stamping process of the longitudinal beam and assure the universal use of other assemblies and parts on trucks within the same series or cross-series. Further, it can reduce the work quantity for layout on the modified truck and facilitate refitting. Therefore, the refitting factory does not need to make additional drilling when refitting, which can protect the paint finish. It can also optimize the piping and wiring, improve the appearance, and facilitate refitting operation.
When the developed width of the longitudinal beam is set, and when the ratio between the height of the web plate and the developed width of the longitudinal beam is equal to 0.75, its resistance to bend is the utmost.
Both upper and lower wing faces of the longitudinal beam should be equal. If there are the upper and lower reinforcement plates, then, the sizes of the upper and lower reinforcement plates should be same.
To improve the resistance to bend of the channel section beam, adhesion of reinforcement plate to the wing face will present better effect than apply it on the web plate. To raise the height of the wing face will produce obvious action to the resistance to bend of the channel section beam.
Drilling on the web plate, especially drilling on area near the neutral shaft, will produce much lesser influence on the bend resisting area factors than drilling on the wing face, and in consideration of the influence of holes on the wing face to the stress concentration, the important conclusion can be made that in principle, no drilling shall be made on the wing face of the channel longitudinal beam of the frame.
For cross beam of complicated forms, the forming process can be analyzed at first so that preliminary judgment can be made to process performance of the cross beam without waiting for completion of the trial manufacturing dies. In such a way, the part forms can be regulated in time so that not only the development time can be saved, but also the waste of tooling dies can be avoided.
Sometimes, the failure cause of parts cannot be concluded via experience. Therefore, the finite element analysis and other methods shall be used to assist the judgment. Most of the strength failure need reinforcement means, however, the increased rigidity is not necessarily a good solution. Instead, the force bearing conditions and deformation tendency should be analyzed according to the position and surrounding environment of the part (structural rigidity and force bearing status) so as to reasonably determine the structural rigidity and strength of the parts designed.
引文
[1]胡亚庄,黄天泽.载重汽车与挂车的车架[M].北京:人民交通出版社,1964.
[2]张洪欣.汽车设计[M].北京:机械工业出版社,1999,第2版.
[3] Takeshi Yoshida,Yasuyuki Kishita, Masaki Shiratori, Tadahiro Shibutani. Development of a Virtual Rough Road Simulator for Motorcycle Frame Strength[J] .SAE,2005-32-0086.
[4]刘岩.自卸汽车车架设计[M].北京:专用汽车,1998,(1):15-18 .
[5]余志生.汽车理论[M].北京:机械工业出版社,1996,第2版.
[6]陈家瑞.汽车构造[M].北京:人民交通出版社,1996,第2版.
[7]蒋孝煜.有限元法基础[M].北京:清华大学出版社,1984,第1版.
[8]张小虞等.汽车工程手册设计篇[M].北京:人民交通出版社,2001,第1版.
[9] Kawakatsu H,Higuchi T.A dual tunneling-unit scanningtunneling microscope.J Vac Sci Technol,1990,B8:319-324.
[10]谷安涛,常国振.汽车车架设计计算的有限元法[J].汽车技术,1977,(6):54-65.
[11]石常青,丁厚明,杨胜梅.货车车架的有限元分析及车厢对其性能的影响.汽车技术,2004(4):5-8.
[12]余传文.重型载货汽车车架结构的有限元仿真及优化[D].吉林:吉林大学硕士学位论文,2004.
[13] D’Aprile,F.(Cent Ricerche Fiat),Icardi,U.Evaluation of vehicle composite structures[J].Proceedings-society of Auto-motive Engnieers,1990,451-4551.
[14] Ao Kazuo,Niiyama Junichi,Matsui Toshharu etc.Analysis of torsional stiffness share rate of truck frame[J].SAE Technical Paper Series,1991,912676,10.
[15] Kim, H.S. And Huh, H.Vehicle Structural collapse Analysis Using a Finite Element Limit Method.Int.J[J]. Vehicle Design,2000,21(4/5)(special issue).
[16]王伟,陈淮等.汽车车架的静强度分析[J].河南:郑州工业大学学报,2000,(9):15-18.
[17] Edmund F., Anthony R..Introduction to formula SAE suspension and frame design[J] .SAE, 1997,971584.
[18] Tae-Eun Chung,Yong-Rae Lee, Chang-Soo Kim.Structural design of aluminum space frame with battery tray[J].SAE,1996,960524.
[19]张义民.机械振动力学[M].吉林:吉林科学技术出版社,2000,第1版.
[20]博弈创作室.ANSYS7.0基础教程与实例详解.中国水利水电出版社,2004,第1版.
[22]周颖等.汽车设计手册.吉林:长春汽车研究所,1998.
[23]刘大维,严天一等.半挂牵引车车架模态分析[J].北京:中国制造业信息化,2006.
[24]王晖云,吕宝占,朱思洪.基于ANSYS的轻型载货汽车车架模态分析[J].煤矿机械, 2007,(03).
[25]杜海珍,荣见华.汽车车架结构的拓扑优化设计[J].机械设计与研究, 2007,(01)
[26]尹辉俊,黄昶春,韦志林,沈光烈,梁双翼.重型车车架的动态特性分析[J].农业机械学报, 2007,(12).
[27]黄贵东,沈光烈,黄昶春,韦志林.汽车车架有限元分析模型的改进与应用[J].装备制造技术, 2007,(02).
[28]黄昶春,韦志林,沈光烈,尹辉俊.考虑横向稳定杆的车架有限元分析[J].装备制造技术, 2007,(02).
[29]王治富,李春平,王路路.解放载货车车架涂装工艺设计[J].汽车工艺与材料, 2007,(03).
[30]王玉平.载货汽车车架承载及使用寿命的分析[J].山西交通科技, 2007,(01).
[31]周岁华.商用车车架工艺技术与材料开发[J].汽车工艺与材料, 2007,(08).
[32]黄贵东,沈光烈,黄昶春,韦志林.汽车车架有限元分析模型的改进[J].机械设计, 2007,(12).
[33]张润生,侯炜.车架刚度及强度的有限元分析[J].拖拉机与农用运输车, 2007,(04).
[34]张承东;冷永杰;刘宾;赵晋红.简析车架刚性.摩托车信息,2003年04期.
[35]刁有明.有限元法在客车骨架分析中的应用[J].装备制造技术, 2007,(10).
[36]殷小霖.基于有限元法的车架轻量化设计[D].武汉理工大学, 2007.
[37]徐芝纶.弹性力学[M].人民教育出版社,1982,第2版.
[38]郑兆昌.机械振动上册[M].机械工业出版社,1980,第1版.
[39]张义民.机械振动力学[M].吉林科学技术出版社,2000,第1版.
[40]博弈创作室.ANSYS7.0基础教程与实例详解[M].中国水利水电出版社,2004.
[41]朱伯芳.有限单元法原理与应用[M].中国水利水电出版社,1998,第2版.
[42]陈精一,蔡国忠.电脑辅助工程分析ANSYS使用指南[M].中国铁道出版社,2001,第1版.
[43]任辉启.ANSYS7.0工程分析实例详解[M].人民邮电出版社,2003,第1版.
[44]龙驭球.有限元法概论[M].人民教育出版社,1978,第1版.
[45]姚杰,刘坤. 1241型重型卡车车架纵梁与横梁联接不同结构方案对比分析[J].辽宁师专学报(自然科学版) , 2007,(01).
[46]马迅,过学迅,赵幼平等.基于有限元法的结构优化与灵敏度分析[J].机械科学与技术,2002,21(4):558-561.
[47]许春雷,鲍际平,吴阳年.轻型载货汽车垂直振动有限元分析[J].北京汽车, 2007,(02).
[48]姚杰,刘坤. 1241型重型卡车主、副车架的各种联接方案下刚度计算对比分析[J].辽宁师专学报(自然科学版) , 2007,(02).
[49]沈炜良,边立静,伍建华.重型载货汽车车架的结构分析及优化设计[J].广西大学学报(自然科学版) , 2007,(03).
[50]苏向玲. 6万辆重型汽车车架新型铆接线的设计[J].汽车与配件, 2007,(30).
[51]陆刚.汽车车架疲劳断裂损坏的焊接修复[J].焊接技术, 2007,(02).
[52]龙凯,覃文洁,左正兴.基于拓扑优化方法的牵引车车架优化设计[J].机械设计, 2007,(06).
[53]李永红,李光耀,刘桂荣.缩减基法在汽车车架分析中应用[J].中国机械工程, 2007,(02).
[54]孙启会;闵鹏.限元法在汽车车架分析中的应用[J].重型汽车2001年05期.
[55]安坤,徐超彦,华道理.国产半挂车未来的发展势头[J].城市车辆, 2007,(08).
[2]张洪欣.汽车设计[M].北京:机械工业出版社,1999,第2版.
[3] Takeshi Yoshida,Yasuyuki Kishita, Masaki Shiratori, Tadahiro Shibutani. Development of a Virtual Rough Road Simulator for Motorcycle Frame Strength[J] .SAE,2005-32-0086.
[4]刘岩.自卸汽车车架设计[M].北京:专用汽车,1998,(1):15-18 .
[5]余志生.汽车理论[M].北京:机械工业出版社,1996,第2版.
[6]陈家瑞.汽车构造[M].北京:人民交通出版社,1996,第2版.
[7]蒋孝煜.有限元法基础[M].北京:清华大学出版社,1984,第1版.
[8]张小虞等.汽车工程手册设计篇[M].北京:人民交通出版社,2001,第1版.
[9] Kawakatsu H,Higuchi T.A dual tunneling-unit scanningtunneling microscope.J Vac Sci Technol,1990,B8:319-324.
[10]谷安涛,常国振.汽车车架设计计算的有限元法[J].汽车技术,1977,(6):54-65.
[11]石常青,丁厚明,杨胜梅.货车车架的有限元分析及车厢对其性能的影响.汽车技术,2004(4):5-8.
[12]余传文.重型载货汽车车架结构的有限元仿真及优化[D].吉林:吉林大学硕士学位论文,2004.
[13] D’Aprile,F.(Cent Ricerche Fiat),Icardi,U.Evaluation of vehicle composite structures[J].Proceedings-society of Auto-motive Engnieers,1990,451-4551.
[14] Ao Kazuo,Niiyama Junichi,Matsui Toshharu etc.Analysis of torsional stiffness share rate of truck frame[J].SAE Technical Paper Series,1991,912676,10.
[15] Kim, H.S. And Huh, H.Vehicle Structural collapse Analysis Using a Finite Element Limit Method.Int.J[J]. Vehicle Design,2000,21(4/5)(special issue).
[16]王伟,陈淮等.汽车车架的静强度分析[J].河南:郑州工业大学学报,2000,(9):15-18.
[17] Edmund F., Anthony R..Introduction to formula SAE suspension and frame design[J] .SAE, 1997,971584.
[18] Tae-Eun Chung,Yong-Rae Lee, Chang-Soo Kim.Structural design of aluminum space frame with battery tray[J].SAE,1996,960524.
[19]张义民.机械振动力学[M].吉林:吉林科学技术出版社,2000,第1版.
[20]博弈创作室.ANSYS7.0基础教程与实例详解.中国水利水电出版社,2004,第1版.
[22]周颖等.汽车设计手册.吉林:长春汽车研究所,1998.
[23]刘大维,严天一等.半挂牵引车车架模态分析[J].北京:中国制造业信息化,2006.
[24]王晖云,吕宝占,朱思洪.基于ANSYS的轻型载货汽车车架模态分析[J].煤矿机械, 2007,(03).
[25]杜海珍,荣见华.汽车车架结构的拓扑优化设计[J].机械设计与研究, 2007,(01)
[26]尹辉俊,黄昶春,韦志林,沈光烈,梁双翼.重型车车架的动态特性分析[J].农业机械学报, 2007,(12).
[27]黄贵东,沈光烈,黄昶春,韦志林.汽车车架有限元分析模型的改进与应用[J].装备制造技术, 2007,(02).
[28]黄昶春,韦志林,沈光烈,尹辉俊.考虑横向稳定杆的车架有限元分析[J].装备制造技术, 2007,(02).
[29]王治富,李春平,王路路.解放载货车车架涂装工艺设计[J].汽车工艺与材料, 2007,(03).
[30]王玉平.载货汽车车架承载及使用寿命的分析[J].山西交通科技, 2007,(01).
[31]周岁华.商用车车架工艺技术与材料开发[J].汽车工艺与材料, 2007,(08).
[32]黄贵东,沈光烈,黄昶春,韦志林.汽车车架有限元分析模型的改进[J].机械设计, 2007,(12).
[33]张润生,侯炜.车架刚度及强度的有限元分析[J].拖拉机与农用运输车, 2007,(04).
[34]张承东;冷永杰;刘宾;赵晋红.简析车架刚性.摩托车信息,2003年04期.
[35]刁有明.有限元法在客车骨架分析中的应用[J].装备制造技术, 2007,(10).
[36]殷小霖.基于有限元法的车架轻量化设计[D].武汉理工大学, 2007.
[37]徐芝纶.弹性力学[M].人民教育出版社,1982,第2版.
[38]郑兆昌.机械振动上册[M].机械工业出版社,1980,第1版.
[39]张义民.机械振动力学[M].吉林科学技术出版社,2000,第1版.
[40]博弈创作室.ANSYS7.0基础教程与实例详解[M].中国水利水电出版社,2004.
[41]朱伯芳.有限单元法原理与应用[M].中国水利水电出版社,1998,第2版.
[42]陈精一,蔡国忠.电脑辅助工程分析ANSYS使用指南[M].中国铁道出版社,2001,第1版.
[43]任辉启.ANSYS7.0工程分析实例详解[M].人民邮电出版社,2003,第1版.
[44]龙驭球.有限元法概论[M].人民教育出版社,1978,第1版.
[45]姚杰,刘坤. 1241型重型卡车车架纵梁与横梁联接不同结构方案对比分析[J].辽宁师专学报(自然科学版) , 2007,(01).
[46]马迅,过学迅,赵幼平等.基于有限元法的结构优化与灵敏度分析[J].机械科学与技术,2002,21(4):558-561.
[47]许春雷,鲍际平,吴阳年.轻型载货汽车垂直振动有限元分析[J].北京汽车, 2007,(02).
[48]姚杰,刘坤. 1241型重型卡车主、副车架的各种联接方案下刚度计算对比分析[J].辽宁师专学报(自然科学版) , 2007,(02).
[49]沈炜良,边立静,伍建华.重型载货汽车车架的结构分析及优化设计[J].广西大学学报(自然科学版) , 2007,(03).
[50]苏向玲. 6万辆重型汽车车架新型铆接线的设计[J].汽车与配件, 2007,(30).
[51]陆刚.汽车车架疲劳断裂损坏的焊接修复[J].焊接技术, 2007,(02).
[52]龙凯,覃文洁,左正兴.基于拓扑优化方法的牵引车车架优化设计[J].机械设计, 2007,(06).
[53]李永红,李光耀,刘桂荣.缩减基法在汽车车架分析中应用[J].中国机械工程, 2007,(02).
[54]孙启会;闵鹏.限元法在汽车车架分析中的应用[J].重型汽车2001年05期.
[55]安坤,徐超彦,华道理.国产半挂车未来的发展势头[J].城市车辆, 2007,(08).