直线振动筛的疲劳寿命分析
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摘要
直线振动筛具有结构简单、振动强度大、筛分效率高、处理能力大等优点,广泛应用于矿山、煤炭、冶炼、建材、化工等领域,用于物料的筛选、脱水、分级等工艺。但由于振动筛在较高振动频率下工作,筛体承受较大的交变激振力,在实际工作中经常出现下横梁断裂,侧板开裂等疲劳破坏,严重影响生产。尤其随着振动筛向大型化方向发展,疲劳破坏更加严重,所以迫切需要在设计阶段进行疲劳寿命分析,提高产品的可靠性。
传统的疲劳寿命预测主要针对具体的物理样机进行试验,耗费大量的人力、物力、财力。而且,如果物理样机试验不合格,还要重新设计,反复试验,直至合格。这样造成大量浪费,开发和测试成本大大提高。随着计算机技术的发展,特别是动力学仿真技术和有限元技术的发展,使得其应用于产品疲劳寿命分析成为可能,克服了传统试验法的不足。
本文借鉴国内外大量的虚拟疲劳耐久性集成化仿真方法,以某大型直线振动筛为研究对象,对其下横梁和侧板进行了疲劳寿命分析。首先利用Pro/E对某大型振动筛零部件进行三维实体建模、组装和干涉检查;然后,利用动力学仿真软件MSC.ADAMS建立了振动筛的多刚体动力学模型,对其进行仿真分析,获得位移、速度、力等信息,为下横梁、侧板的刚柔耦合动力学分析提供了刚体模型;利用有限元前后处理器MSC.PATRAN,求解器MSC.NASTRAN分别对下横梁和侧板进行自由模态分析,获得固有频率和固有振型,为疲劳寿命分析提供了模态信息和柔性体;而后,在MSC.ADAMS中,分别建立了以下横梁、侧板为柔性体,其它零部件为刚性体的刚柔耦合动力学模型,为疲劳寿命分析的载荷谱提供了模态位移;最后,在疲劳分析软件MSC.FATIGUE中,根据材料的S-N曲线,利用模态应力恢复法分别对下横梁和侧板进行疲劳寿命分析,获得其疲劳寿命云图和结构危险部位。
通过对该振动筛疲劳寿命分析结果与实际破坏情况相比较,二者相互吻合,说明这种虚拟疲劳耐久性集成化分析系统应用于振动筛的疲劳寿命分析是可行的,它能够减少物理样机的数量,缩短产品的开发周期,进而降低开发成本,提高市场竞争力。同时,本文的研究对振动筛的可靠性设计具有一定的参考和借鉴价值。
Linear vibrating sieve is widely used in mining, coal, metallurgy, building materials, chemical industry etc., for materials selection, dehydration, grading etc., due to its simple structure, strong vibration intensity, high screening efficiency and processing capacity etc.. However, the body has to bear a larger alternating excitation force at higher vibrating frequency, so it often appears fatigue damage such as cracking of the lateral plate and beams in practical work, which is seriously affecting production. Especially with the development of vibrating sieve towards large-scale direction, fatigue damage is becoming more severe. It is urgent to improve the fatigue life of the reliability of products in the design stage.
Traditional prediction of fatigue life focuses on specific physical prototype tests, which is a waste of manpower, materials and financial resources. Moreover, if the physical prototype test fails, it is need to re-design the product and check errors until success, result in substantial increase in development and test costs. With the development of computer technology, especially the dynamics simulation and finite element technology, it becomes possible to be applied in product fatigue life analysis, overcoming the shortcomings of the traditional test methods.
Based on some linear vibrating sieve, this paper analyses fatigue life of the beams and lateral plate according to a large number of virtual fatigue durability integrated simulation methods at home and abroad. Firstly, 3-D models of sieve parts are established,assembled and checked interference by Pro/E. Secondly, the multi-rigid-body dynamics model of vibrating sieve is established through MSC.ADAMS, and the simulation analysis is carried on, obtaining displacement, velocity and force, etc., which provides a rigid model for the rigid-flexible coupling dynamic analysis of the beam and lateral plate. Thirdly, free modal analysis is carried on through finite element processor MSC.PATRAN and solver MSC.NASTRAN respectively, acquiring the natural frequencies and natural mode of vibration, which provides the modal information and flexible body for fatigue life analysis. Then, the rigid-flexible coupling dynamic model is established with the beam and lateral plate being the flexible body, the other parts the rigid body in MSC.ADAMS, which provides modal displacement for the load spectrum for fatigue life analysis. Finally, the beam and lateral plate are analyzed by using modal stress recovery method in fatigue analysis software MSC.FATIGUE, according to the material S-N curve, in order to obtain the fatigue life of Moire figure and structure of dangerous position.
The result of the fatigue life analysis is in accordance with actual damage, indicating it is feasible for the virtual fatigue durability integrated analysis system to be applied in vibrating sieve fatigue life analysis, which can reduce the number of physical prototypes, shorten the development cycle of products, reduce development costs and improve market competitiveness. At the same time, this paper has a certain reference value for further studies on the reliability of the vibrating sieve.
传统的疲劳寿命预测主要针对具体的物理样机进行试验,耗费大量的人力、物力、财力。而且,如果物理样机试验不合格,还要重新设计,反复试验,直至合格。这样造成大量浪费,开发和测试成本大大提高。随着计算机技术的发展,特别是动力学仿真技术和有限元技术的发展,使得其应用于产品疲劳寿命分析成为可能,克服了传统试验法的不足。
本文借鉴国内外大量的虚拟疲劳耐久性集成化仿真方法,以某大型直线振动筛为研究对象,对其下横梁和侧板进行了疲劳寿命分析。首先利用Pro/E对某大型振动筛零部件进行三维实体建模、组装和干涉检查;然后,利用动力学仿真软件MSC.ADAMS建立了振动筛的多刚体动力学模型,对其进行仿真分析,获得位移、速度、力等信息,为下横梁、侧板的刚柔耦合动力学分析提供了刚体模型;利用有限元前后处理器MSC.PATRAN,求解器MSC.NASTRAN分别对下横梁和侧板进行自由模态分析,获得固有频率和固有振型,为疲劳寿命分析提供了模态信息和柔性体;而后,在MSC.ADAMS中,分别建立了以下横梁、侧板为柔性体,其它零部件为刚性体的刚柔耦合动力学模型,为疲劳寿命分析的载荷谱提供了模态位移;最后,在疲劳分析软件MSC.FATIGUE中,根据材料的S-N曲线,利用模态应力恢复法分别对下横梁和侧板进行疲劳寿命分析,获得其疲劳寿命云图和结构危险部位。
通过对该振动筛疲劳寿命分析结果与实际破坏情况相比较,二者相互吻合,说明这种虚拟疲劳耐久性集成化分析系统应用于振动筛的疲劳寿命分析是可行的,它能够减少物理样机的数量,缩短产品的开发周期,进而降低开发成本,提高市场竞争力。同时,本文的研究对振动筛的可靠性设计具有一定的参考和借鉴价值。
Linear vibrating sieve is widely used in mining, coal, metallurgy, building materials, chemical industry etc., for materials selection, dehydration, grading etc., due to its simple structure, strong vibration intensity, high screening efficiency and processing capacity etc.. However, the body has to bear a larger alternating excitation force at higher vibrating frequency, so it often appears fatigue damage such as cracking of the lateral plate and beams in practical work, which is seriously affecting production. Especially with the development of vibrating sieve towards large-scale direction, fatigue damage is becoming more severe. It is urgent to improve the fatigue life of the reliability of products in the design stage.
Traditional prediction of fatigue life focuses on specific physical prototype tests, which is a waste of manpower, materials and financial resources. Moreover, if the physical prototype test fails, it is need to re-design the product and check errors until success, result in substantial increase in development and test costs. With the development of computer technology, especially the dynamics simulation and finite element technology, it becomes possible to be applied in product fatigue life analysis, overcoming the shortcomings of the traditional test methods.
Based on some linear vibrating sieve, this paper analyses fatigue life of the beams and lateral plate according to a large number of virtual fatigue durability integrated simulation methods at home and abroad. Firstly, 3-D models of sieve parts are established,assembled and checked interference by Pro/E. Secondly, the multi-rigid-body dynamics model of vibrating sieve is established through MSC.ADAMS, and the simulation analysis is carried on, obtaining displacement, velocity and force, etc., which provides a rigid model for the rigid-flexible coupling dynamic analysis of the beam and lateral plate. Thirdly, free modal analysis is carried on through finite element processor MSC.PATRAN and solver MSC.NASTRAN respectively, acquiring the natural frequencies and natural mode of vibration, which provides the modal information and flexible body for fatigue life analysis. Then, the rigid-flexible coupling dynamic model is established with the beam and lateral plate being the flexible body, the other parts the rigid body in MSC.ADAMS, which provides modal displacement for the load spectrum for fatigue life analysis. Finally, the beam and lateral plate are analyzed by using modal stress recovery method in fatigue analysis software MSC.FATIGUE, according to the material S-N curve, in order to obtain the fatigue life of Moire figure and structure of dangerous position.
The result of the fatigue life analysis is in accordance with actual damage, indicating it is feasible for the virtual fatigue durability integrated analysis system to be applied in vibrating sieve fatigue life analysis, which can reduce the number of physical prototypes, shorten the development cycle of products, reduce development costs and improve market competitiveness. At the same time, this paper has a certain reference value for further studies on the reliability of the vibrating sieve.
引文
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[2]袁熙,李舜酩.疲劳寿命预测方法的研究现状与发展[J].航空制造技术,2005,(12): 80-84.
[3]MSC.Software公司北京办事处.MSC.Software虚拟疲劳耐久性集成化仿真分析系统[J].CAD/CAM与制造业信息化,2004,(9):129-132.
[4]王正浩,范改燕.振动筛结构强度研究的现状[J].沈阳建筑工程学院学报,1999,15(3):278-281.
[5]姚家华,杨民献.大型振动筛横梁的强度和应力集中问题的研究[J].矿山机械,1989,(2):29-32.
[6]周广林,张维屏.大型振动筛的强度分析[J].矿山机械,1990,(9):29-31.
[7]马学东,王律躬,崔文好等.2ZKX2148型直线振动筛侧板的有限元动力学分析[J].鞍山钢铁学院学报,1999, 22(1):32-35.
[8]傅莉,宋晓梅,高静.2ZKx1760型直线振动筛动强度分析[J].沈阳大学学报,2001, 13(4):58-60.
[9]方治华,赵爽.HFZS1640型振动筛强度的优化设计[J].煤矿机械,2007,28(11):23-24.
[10]郭勤涛,张翠萍,魏少强.2ZK3675直线振动筛疲劳强度的可靠性设计[J].选煤技术,2000,(5):23-25.
[11]丛楠.军用工程机械虚拟疲劳试验研究[D].长沙:国防科学技术大学,2006.
[12]R.K.Luo,B.L.Gabbitas,B.V.Brickle.An intergrated dynamic simulation of metro vehicle in a real operating environment[J].Vehicle System Dynamics,1994,23: 334-345.
[13]R.K.Luo,B.L.Gabbitas,B.V.Brickle.Fatigue design in railway vehicle bogies based on dynamic simulation[J].Vehicle System Dynamics,1996,25:438-449.
[14]Stefan Dietz,Helmuth Netter,Sachau.Fatigue life prediction of a railway bogie under dynamic loads through simulation[J].Vehicle System Dynamics,1998,29(6):385-402.
[15] Stefan DIETZ,Klaus KNOTHE,Willi KORTüM.Fatigue Life Simulations Applied to Railway Bogies[C].The 4TH International Conference on railway bogies and running gears,1998,9.
[16]H.Riener, D.Peiskammer, W.Witteveen.Modal Durability analysis of a passenger cars front suppoting flame due to full vehicle simulation loads[C].ADAMS User Conference 2001-North America.
[17]林晓斌.虚拟疲劳寿命与工程设计[C].中国科协青年科学家论坛:虚拟工程与科学.北京:中国科学技术出版社,2001:100-110.
[18]钱峰,张治.汽车零部件计算机模拟疲劳试验研究[J].北京汽车,2002,(4):15-17.
[19]孟广伟,王成国,刘敬辉等.用虚拟疲劳样机技术分析转8A型转向架侧架的疲劳寿命[J].中国铁道科学,2002,23(4):8-11.
[20]阳光武,肖守讷,金鼎昌.基于虚拟样机技术的地铁车辆构架疲劳寿命仿真[J].机车电传动,2004(3):39-41.
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