【作者】 李艳君；

【导师】 刘玉君； 纪卓尚；

【作者基本信息】 大连理工大学 ， 船舶与海洋结构物设计制造， 2005， 博士

【摘要】 船舶精度控制技术是提高船舶质量,降低生产成本的主要手段。国外先进造船国家已经在船舶精度控制方面有所突破,日立造船公司有明工厂已经做到从下料直到大合拢,实现了分段全方位无余量,均以补偿量代替余量,并且已从船体扩展到舾装、管系,达到了全方位无余量。国内精度控制技术也已开展多年,但目前大多数船厂仍然立足于分段无余量上船台,对于从零件下料即开始以补偿量代替余量的全过程精度控制技术研究推广程度较差,缺乏对补偿量的理论研究。 本论文对船舶精度控制关键技术进行了重点研究。 一,运用尺寸链原理,解决误差传递以及公差分配问题,然后将尺寸链原理应用到船舶重量重心精度控制数据库中。运用船舶重量重心精度控制数据库,船厂可以根据尺寸链的误差传递及公差分配计算方法对重量重心位置进行监控和调整。 二,应用热弹塑性有限元方法研究了焊接角变形问题,并进行了实验验证。如何施加弹性反变形是这一部分研究的主要内容。本文将利用MSC. software开发的软件MSC. Marc进行焊接结构的热弹塑性有限元模拟,对不同面板厚度焊接结构在不同线能量条件下进行热弹塑性有限元模拟。通过计算结果分析,焊接前施加弹性反变形的结构在焊接后角变形趋于零。通过焊接试验验证了该结论。 三,介绍了船舶结构尺寸链中补偿环的设置与计算,并且建立了补偿量数据库,同时应用BP神经网络技术对焊接补偿量进行建模研究。建立了部分零部件加工变形规律的数学模型,为部分零部件加工所需补偿量的设计提供了定量依据,为全船实施零部件补偿量的精度控制方法奠定了基础。更多还原

【Abstract】 Ships’ accuracy control technique is an important means to ensure ships’ quality and reduce the cost of production. Many advanced countries have improved in ships’ accuracy management. Youming shipyard in Japan has no residual quantity in all blocks during the manufacturing. Domestic ships’ accuracy control technique has been developed for many years, but most shipyards have no residual quantity only during producing blocks. Ships’ accuracy control technique has been extended lowly, which has only compensated quantity instead of residual quantity during whole ships’ production. And the research of compensated quantity is deficient.This paper has researched the system of ships’ accuracy control technique and applies size chain principle to ships’ accuracy management.The paper has managed the problems of error transfer and tolerance assign of ships’ dimension by the principle. We have built the database about ships’ weight and centre of gravity by the probabilistic technique of the principle. Shipyards can monitor and control ships’ weight and centre of gravity during the whole production from design to complete.The paper has researched weld distortion by thermal elasto-plastic finite element techniques, and carried out an experiment. The main content is how to force elastic reversed angular distortion. This paper has simulated the welding process of the T-Joint Fillet Structures used thermal elasto-plastic finite element techniques by MSC’s MSC.Marc/ MSC.Patran. The study has calculated the distortion of the structures which are different thickness and are thrown different heat flow. According to analysis of calculating result, the structures thrown elastic reversed angular distortion before welding have no angular distortion after welding. An experiment has been carried out in Dalian Shipyard that prove elastic reversed angular distortion is effective means to control weld distortion in ships’ accuracy management.The research has introduced the compensation database simply and used the practice data from Dalian Shipyard to study mathematical models construction for weld shrinkage by BP neural network. This paper has built the mathematical model calculating components compensation value by welding distortion.更多还原