柔性管道骨架层成形工艺设计及有限元分析

发布时间：2018-05-01 12:11

本文选题：柔性管道骨架层 + 辊弯成形　；参考：《大连理工大学》2015年硕士论文

【摘要】：随着陆地资源的逐渐消耗和海洋资源开采技术的飞速发展,海洋油气运输管道的需求量日益增加。由于柔性管道有着许多普通运输管道无法具备的优异性能,在很多海洋开采工程中必须或优先考虑使用柔性管道。柔性管道由多层金属铠装层以及多层聚合物层组成,骨架层(carcass)作为最内层,需要在满足一定柔性的前提下防止由于外层压力导致的内层聚合物层的压溃现象,其结构是一种特定型材螺旋缠绕的互锁金属结构。骨架层的制造工艺十分复杂,是柔性管道生产中的核心技术之一。本文采用有限元仿真方法研究了骨架层的制造工艺,探讨了柔性管道骨架层成形的关键技术。制造骨架层的核心技术是辊弯成形工艺。本文基于辊弯成形过程中板带与轧辊的接触情况,建立了描述板带变形特征的数学模型,该模型可以预测弯曲角分布和纵向应变变化情况。结果表明：板带的纵向应变大小与变形截面以及轧辊尺寸有关,纵向应变在道次之间呈现先升高后降低规律,峰值出现在第一接触点处；随着边腿长度的增加,纵向应变期初呈增加,随后呈降低,拐点出现在边腿长度为约12mm处；纵向应变峰值随着轧辊半径的增加而减小。为探索合理的板带成形有限元模拟参数,本文运用有限元软件MARC/mentat 2012进行了三道次U型型材的辊弯成形模拟和Ti-6A1-4V板料的自由弯曲回弹模拟,并将模拟结果与实验结果进行了对比分析。结果表明：所选择的模拟参数能够较好模拟板材的折弯变形特征；实体壳单元(M-RESS)在模拟板带折弯成形,尤其在需要预测回弹时,有良好的表现；合理的网格划分和厚度方向积分点数的选择对回弹值的预测有着很大影响。在参考已有辊弯成形原理的基础上,设计了骨架层的成形辊花图,采用经论证的模拟参数,建立了骨架层辊弯成形的有限元模型。根据成形的模拟结果进行辊花图的参数反馈与优化,最终确定出合理的工艺设计方案。此外,还进行了锁扣压轮组的设计,并给出了锁扣机的简要整体三维造型,为柔性管道骨架成形设计与制造提供技术依据。
[Abstract]:With the gradual consumption of land resources and the rapid development of marine resource mining technology, the demand of offshore oil and gas transportation pipeline is increasing day by day. Due to the excellent performance of many ordinary transportation pipelines, flexible pipelines must be used or given priority in many marine mining projects. The flexible pipeline consists of multi-layer metal armor layer and multi-layer polymer layer, and the skeleton layer carcassas is the innermost layer. It is necessary to prevent the inner polymer layer from collapsing due to outer pressure under certain flexibility. Its structure is a kind of interlocking metal structure with special profile spiral winding. The manufacturing process of skeleton layer is very complex and is one of the core technologies in flexible pipeline production. In this paper, finite element simulation method is used to study the manufacturing process of skeleton layer, and the key technology of forming flexible pipeline skeleton layer is discussed. The core technology of manufacturing skeleton layer is roll forming process. Based on the contact between strip and roll during roll bending, a mathematical model describing the deformation characteristics of plate and strip is established. The model can predict the distribution of bending angle and the variation of longitudinal strain. The results show that the longitudinal strain of plate and strip is related to the deformation section and roll size. The longitudinal strain increases first and then decreases between passes, the peak value appears at the first contact point, and with the length of side leg increasing, The longitudinal strain increases at the beginning of the period, then decreases, and the inflection point appears at the side leg length of about 12mm, and the peak value of the longitudinal strain decreases with the increase of the roll radius. In order to explore the reasonable finite element simulation parameters of strip forming, the roll forming simulation of three times U-shaped profile and the free bending springback simulation of Ti-6A1-4V sheet metal were carried out by using the finite element software MARC/mentat 2012. The simulation results are compared with the experimental results. The results show that the selected simulation parameters can well simulate the bending deformation characteristics of the plate, and the solid shell element M-RESS has a good performance in simulating strip bending forming, especially when the springback prediction is needed. Reasonable mesh division and the selection of integral points in thickness direction have great influence on the prediction of springback value. Based on the principle of roll bending, the forming roll pattern of skeleton layer is designed, and the finite element model of roll bending forming of skeleton layer is established by using the proved simulation parameters. According to the result of forming simulation, the parameter feedback and optimization of roll pattern are carried out, and the reasonable process design scheme is finally determined. In addition, the design of lock press wheel set is carried out, and the brief 3D modeling of lock machine is given, which provides the technical basis for the design and manufacture of flexible pipeline skeleton.
【学位授予单位】：大连理工大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE973

【共引文献】