浅谈船舶铅封管理

目前,船舶铅封工作正在全国范围内深入开展,本文结合笔者自己的工作实践,以某大型远洋船舶为例,着重介绍了如何阅读机舱油污水管系图以及如何对其实施铅封管理工作。     

圆管涵承载能力的研究

采用有限元方法和结构力学方法对圆管涵进行力学分析，通过对2种方法之结果的比较，定量分析了早几年圆管涵普遍开裂的原因。在此基础上提出一种圆管涵的合理结构形式，并介绍了这种结构形式在实际应用中的良好效果。理论和实践证明，提出的这种结构形式具有优良的结构承载性能。     

船舶压载水管理系统管径的选择

本文主要介绍BalClOr○R压载水管理系统中主要管路直径的设计方法与选择的依据,进一步规范了压载水管理系统中管道直径与流速的设计,从而避免了由于管路压力降太大而出现的各种问题。     

船舶管材管附件集配管理系统建模及应用

现代造船模式主要是以“中间产品组织生产”为基本特征,其显著特点是生产管理均以托盘管理为核心进行展开.本文重点阐述了管材管附件的集配送管理流程及相应的系统功能模块.通过建立管理模型,使计划、托盘与实物有机统一,实现其管理信息化、科学化、规范化的目的.     

管道对口器技术及方案研究

水下油气管道维修是人类开发海洋资源的重要保障,文中对西方发达国家正在研究或使用于铺设、维修管道的对口器进行了综述,并针对海底油气输送管道维修目标提出了一种对口器的总体方案.对于追踪国外先进科技,设计适合维修作业环境的对口器,提高我国水下作业技术有重要的意义.     

洞室地基失稳模式及影响因素分析

本文主要通过对岩石洞室地基的破坏失稳模式,以及洞室的破坏模式的分析,简单地提出了洞室地基稳定性判据和洞室地基失稳的影响因素。     

MSEMD排气系统扩压长支管定常流动研究

本文用数值方法研究了ＭＳＥＭＤ系统轴对称扩压长支管的定常流动特性。在贴体坐标系中用与时间相关的二维流动计算方法对湍流流动的控制方程进行了数值求解，用二阶ＭａｃＣｏｒｍａｃｋ差分方法处理内部节点，用二阶参考平面上的特征线法处理进、出口边界条件，并把计算结果与实测结果进行了比较，它们之间吻合得相当好。     

港珠澳大桥珠海连接线拱北隧道曲线管幕9号管脱困方案研究

港珠澳大桥拱北隧道曲线管幕施工阶段,由于始发端深基坑突发涌水、涌砂,造成顶管施工区域地层严重失水和管周润滑泥浆流失,9号管顶进被困。根据顶管施工区域工程环境、地质条件和地层变形情况,以及9号管被困位置和施工装备条件因素,按照"不危及施工安全和避免发生次生灾害,可操作性强,处置费用低"的原则,提出了增加后背顶力、中继套管顶推、逆向开挖拉拔、顶部开窗等4种递进脱困方案。经比选,首先采用了增加后背顶力方案未果,后采用中继套管推进方案,取得了成功。9号管成功脱困为本工程后续顶管施工积累了经验,也为类似工程施工提供了借鉴。     

Algorithmic formulation of clay and sand pipe–soil interaction models for on-bottom stability analysis

This paper presents a new algorithmic formulation of the clay and sand pipe–soil interaction models recommended by the DNV-RP-F109 code for dynamic on-bottom stability analysis of submarine pipelines. The pipe–soil force update algorithm is formulated within the framework of computational elasto-plasticity and applies Backward-Euler integration to ensure stability and robustness for large time step sizes. Algorithmic optimization techniques are developed by utilizing a closed-form solution and subincrementation. A numerical verification study covering full cyclic displacement ranges of a 12 inch pipeline is presented. The new formulation is shown to increase the time step size by a factor of up to 50 compared to commercial software tools for on-bottom stability analysis. This achievement will be particularly beneficial for long-duration 3D nonlinear time domain on-bottom stability analysis.     

Finite element analyses of corroded pipeline with single defect subjected to internal pressure and axial compressive stress

This paper describes the application of finite element method (FEM) and the development of equations to predict the failure pressure of single corrosion affected pipes subjected to internal pressure and axial compressive stress. The finite element analysis (FEA) results were verified against full-scale burst tests and theoretical calculations. Material non-linearity, which allow for large strains and displacements, were considered. In addition, true UTS instead of engineering UTS was used to determine the point of failure. The pipes used in the FEA was modelled based on API 5L X52 modified steel with a length of 2000 mm, a nominal outer diameter of 300 mm, and a nominal wall thickness of 10 mm. The results obtained from FEA were compared to that of existing comprehensive corrosion assessment method, known as DNV-RP-F101. Six equations, utilizing the Buckingham's π theorem and multivariate non-linear regression techniques, were developed for predicting the failure pressure of corroded pipeline with single defect subjected to both internal pressure and axial compressive stress. These equations provide improved failure pressure predictions with good margins of errors (less than 10%).