【作者】 夏东强；

【导师】 温彤；

【作者基本信息】 重庆大学 ， 材料加工工程， 2008， 硕士

【摘要】 管材弯曲件大量应用于气体、液体的输送管路以及机械结构等方面。作为管材塑性加工的重要组成部分,随着近年来经济的迅速发展,管材的弯曲成形受到了大量关注并得到了充分的发展。其中,小半径弯管是弯管研究的一个热点,这是因为小半径弯管件有着非常广泛的应用,尤其是在航空航天、汽车等高技术领域,小半径弯管件已成为了一个关键的零件。另外,绕弯是最常用的弯管方法,但传统的绕弯工艺中,一套模具只能弯曲一种直径的管材,当弯曲不同直径的管材时需要更换模具,导致劳动生产率的降低和成本的增加。本文以一种新型的小半径弯曲工艺——管材剪切弯曲工艺和管径可调的通用弯管工艺为对象,对一些弯管的热点问题进行了理论与实验研究,主要包括:①总结了常用的管材弯曲方法和小半径弯管技术,综述了这一领域的研究成果。②分析了管材弯曲成形的受力与变形,介绍了管材弯曲的失效形式及常用的解决措施。③介绍了管材剪切弯曲的原理。然后通过有限元方法对管材剪切弯曲成形过程进行了数值模拟,分析了成形过程中的材料变形以及成形力的变化规律,总结了材料参数、相对弯曲半径、相对壁厚等对成形的影响。④对所提出的管径可调的通用绕弯模具进行了实验验证,分析和总结了实验数据,证明了该方案的可行性。然后将实验结果与数值模拟结果对比,总结了该方案成形过程中的规律。更多还原

【Abstract】 Tube bending is the important part of tube plastic processing. The bending components, which made of tube, regardless of planar or spatial, are widely applied in metal structure and transfer piping for gas and liquid. Therefore research on tube bending is one of the most important fields which obtain most attention and develop rapidly. In recent years, along with deep research and development, small radius-tube bending becomes one of the hot spots on tube bend processing research. The application of the small radius bending parts is very widespread, and the small radius bend parts have been the crucial elements especially in high-tech domain such as the aviation, astronautics and so on.The primary content of the paper is as follow:①The common tube bending method and tube bending technology with small bending radius are introduced briefly and the research results of some experts are presented.②The stress state of bending forming is analyzed and the deformation degree of the bending forming is discussed, and the models and resolution of failure in bending forming are presented then.③The principle of the tube shear bending is analyzed in detail, and three-dimensional dynamic model and the finite element model are established.④By finite element analysis software DEFORM-3D, the forming process of tube shear bending is simulated numerically. Its forming process is analyzed, and its forming mechanism is expounded, and the law of forming load——stroke is opened out. Then, the influence rule are generalized about material parameter, the relative bending radius, the relative wall thickness to forming.It can be proved that the research results in this paper are practically available for accelerating the application and development of tube bending and especially tube bending with small bending radius, and present a new method for the research of tube bending.更多还原