共查询到19条相似文献,搜索用时 609 毫秒
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《机械制造与自动化》2016,(5):118-120
四轴滚弯是常用来成形大尺寸型材的有效方法。针对典型2024铝合金框板零件,利用大型非线性有限元软件ABAQUS对其四轴滚弯过程进行了有限元数值分析,获得了滚弯过程中的工艺参数。结果表明,当左右滚轮上升量为35 mm时,可成形该框板零件;随着左右滚轮上升量的增加,成形曲率半径减小。滚弯过程中,框板应力中性层位于腹板部位且框板经历先加载后卸载的2个阶段。 相似文献
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基于有限元分析的二轴柔性滚弯过程影响因素的研究 总被引:2,自引:0,他引:2
利用弹性介质对钣金件进行二轴柔性滚弯成形是一种先进的钣金制造工艺,将弹性介质(聚氨酯橡胶)的冲压优势和传统滚弯原理结合,成为钣金成形领域的一个新的发展方向。本文利用有限元软件MARC建立二轴柔性滚弯过程的有限元分析模型,成功的模拟了板料滚弯成形及回弹的加工过程,对工件滚弯成形过程的主要影响因素进行了分析,给出了压入深度、柔性层厚度、刚性滚轴半径、材料性能与回弹后曲率半径的关系。分析结果表明,有限元模拟对滚弯过程的工艺参数选取有着一定的指导意义。 相似文献
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HE Anrui YANG Quan CHEN Xianlin ZHAO Lin 《机械工程学报(英文版)》2008,21(3):103-107
Varying contact-length backup roll and linearly variable crown work roll are provided for improving the mill performance of profile and flatness control. Integrated with theses technologies, relevant profile and flatness control models are developed for hot strip mills on the basis of large amount of finite element calculation. These models include shape setup control model in process control system, bending force feedforward control model, crown feedback control model and flatness feedback control model in basis automation system. Such a profile and flatness control system with full functions is applied in 1 700 mm industrial hot strip mills of Ansteel. Large amount of production data shows that the crown precision with the tolerance of±18 μm is over 90%, the strip percentage which the actual flatness is within ±25 I-unit surpasses 96%, and general roll consume is reduced by 28% by using the profile and fiatness control system. In addition, schedule-free rolling is realized. 相似文献
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Francesco Lambiase 《The International Journal of Advanced Manufacturing Technology》2014,71(5-8):1285-1293
In the shape rolling process, the reduction of the number of passes is a challenging topic for the steel industry. This can be achieved by enhancing the design approach or by developing new rolling passes that allow the production of high cross-section reductions such as with the slit roll pass. However, in order to design a robust roll pass, the lateral spread of the workpiece must be predicted correctly to prevent incomplete, or even worse, excessive roll groove fulfilling (which may cause roll damage). In the present investigation, the possibility of using a finite element model to predict the lateral spread in a slit roll pass is investigated. The results of the finite element model are then used to adapt and calibrate two analytical models that were developed originally for strip rolling and shape rolling with concave grooves. 相似文献
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This paper describes details of a finite element model for analysing three-dimensional flow in the roll gap during radial ring rolling between plain cylindrical rolls. The model considers such factors as curvature of the workpiece, unequal roll diameters and the fact that the inner roll or mandrel is unpowered. The results of the analysis compare favourably with experimental observations. Fishtailing is predicted satisfactorily, also the form of the pressure distribution in the roll gap, which shows twin peaks under some rolling conditions. The method has the merits of easy handling and short calculation time. It should be a useful aid to the design of ring rolling and other asymmetric rolling processes. 相似文献
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Flexible roll forming is a promising manufacturing method for the production of variable cross section products. Considering the large plastic strain in this forming process which is much larger than that of uniform deformation phase of uniaxial tensile test, the widely adopted method of simulating the forming processes with non-supplemented material data from uniaxial tensile test will certainly lead to large error. To reduce this error, the material data is supplemented based on three constitutive models. Then a finite element model of a six passes flexible roll forming process is established based on the supplemented material data and the original material data from the uniaxial tensile test. The flexible roll forming experiment of a B pillar reinforcing plate is carried out to verify the proposed method. Final cross section shapes of the experimental and the simulated results are compared. It is shown that the simulation calculated with supplemented material data based on Swift model agrees well with the experimental results, while the simulation based on original material data could not predict the actual deformation accurately. The results indicate that this material supplement method is reliable and indispensible, and the simulation model can well reflect the real metal forming process. Detailed analysis of the distribution and history of plastic strain at different positions are performed. A new material data supplement method is proposed to tackle the problem which is ignored in other roll forming simulations, and thus the forming process simulation accuracy can be greatly improved. 相似文献
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A 3-D finite element method analysis of cold rolling of thin strip with friction variation 总被引:3,自引:0,他引:3
In this paper, a three-dimensional rigid-plastic finite element method (FEM) model to simulate the cold rolling of thin strip with different friction models is described. The effects of rolling parameters, such as work roll diameters and reductions, are analysed in this study. The simulation and experimental values of rolling pressure and spread (the difference of strip width before and after rolling) show a good agreement when friction variation in the roll bite is considered. The roll separating force, spread and forward slip for constant friction and friction variation models are also compared. The friction variation in the roll bite has a significant effect on the simulation results. 相似文献
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Prediction model of the exit cross sectional shape of workpiece in round-oval-round pass rolling 总被引:1,自引:0,他引:1
A reliable analytic model that predicts the surface profile of the exit cross section of workpiece in round-oval (or oval-round)
pass sequence is established. The presented model does not require any plasticity theory but needs the only geometric information
on workpiece and roll groove. Formulation is based on the linear interpolation of the radius of curvature of an incoming workpiece
and that of roll groove in the roll axis direction when the maximum spread of workpiece is known beforehand. The validity
of the analytic model is examined by hot rod rolling experiment with the roll gap, specimen size, design parameter of oval
groove and steel grade changed. Results revealed that the cross sectional shapes predicted by the model were in good agreement
with those obtained experimentally. We found that the analytic model not only has simplicity and accuracy for practical usage
but also saves a large amount of computational time in comparison with finite element method. 相似文献