拖曳锚安装缆绳在海床土中的嵌入特性

在深水或超深水海洋油气资源的开发中广泛应用的新型拖曳锚,由于受到安装缆绳拖曳力的作用会逐渐嵌入海床,在海床土体中安装缆绳嵌入段长度的变化规律体现了缆绳的嵌入特性,对锚板的精确定位和优化安装具有重要意义.基于嵌入缆绳单元的受力模型,建立粘性土和无粘性土中嵌入段缆绳长度的理论预测公式,分析预测受力模型的关键参数对嵌入段缆绳长度的影响,并采用可视化追踪技术对理论模型进行验证.     

深水管线安装技术

在过去的几年里,深水管线铺设经历了快速的发展,目前可以预测的是油气开采水深可以达到3 600 m,未来必将突破这个限度。现在各种海底管道的安装方法在海洋深水市场中都有各自的优点,在线结构物和钢悬链立管可以进行安全高效地安装,管道的旋转也能被有效地控制,海上维修技术也已经被证实。文章介绍了深水管道及附属结构物的几种常用的安装方法,并对管线铺设水深的限制进行分析,供同行参考。     

水下爆炸冲击波和气泡脉动的数值模拟研究

运用AUTODYN程序对水下爆炸冲击波和气泡脉动进行了数值模拟研究.首先模拟了无限水域中的水下爆炸冲击波,然后将深水爆炸简化为一维问题,采用一维方法对深水爆炸冲击波和气泡脉动进行了数值模拟,并将模拟结果与经验公式和实验结果进行了比较.模拟结果表明,AUTODYN能准确模拟近场水下爆炸冲击波和深水爆炸气泡脉动过程,计算得到的近场水下爆炸冲击波峰值压力和比冲量、水质点速度、气泡最大半径、脉动周期、二次压力波的峰值压力和比冲量等特性参数均与经验公式、理论公式和实验结果吻合良好.远场的冲击波峰值压力的计算值小于经验值,而且计算误差随着爆距的增加而增大.最后总结了模拟结果,得出了对工程应用有益的结论.     

水下管道连接器设计研究及应用

随着全球海洋石油天然气开发从浅水走向深水,由于潜水员下潜深度有限,海底油气管道的连接必须通过水下机器人代替潜水员完成此项工作。因此各种管道连接技术也越来越多地应用于海洋石油开发中。水下管道连接器作为一种重要的自动安装连接装置,涉及到机械、液压、材料、防腐、密封等各个方面,具有免潜水员操作、安装便捷、可靠性高等特点,可广泛应用于水下油气管道连接。本文对已成功应用于南海某气田中水下采气树跨接管连接的水平机械式管道连接器和水下管汇发球器连接的垂直液压式管道连接器,从密封结构、导向结构、锁紧结构的设计进行了深入的阐述,并在连接器样机型式试验、产品防腐、水下安装等方面也进行了详细的说明。     

美国船级社(ABS)发布2021版《海洋系泊系统纤维缆绳应用指南》

正美国船级社于近日发布2021版《海洋系泊系统纤维缆绳应用指南》,这份指南旨在为海运业海洋系泊系统中使用的纤维缆绳提供标准化要求。本指南提供了入级ABS船级社并由ABS认证的海洋系泊系统纤维缆绳的设计、材料、测试、生产、安装以及相关检验标准。本指南将取代1999年出版的《ABS海洋系泊合成缆绳应用指南》。制定本指南的主要目的是反映最新的技术发展以及纤维缆绳在海洋系泊系统中的最新行业应用。     

深水多功能水下工程作业船结构设计

深水多功能水下工程作业船是一艘配置大型水下工程作业装备、集成多项水下作业功能的深水海域油气田开采配套船舶。该船集大型深水水下结构物安装、柔性管/电缆铺设、水下机器人(ROV)、锚系处理和潜水支持等多项功能于一身。该船安装以及预设作业功能布置的大型作业设备,体积庞大、额定负荷高,船体结构要承受巨大的作业载荷。同时根据深水工程作业的要求,设备的配置和船体结构布局需要综合协调优化,以满足船体结构的强度要求和深水水下工程作业的功能实现。     

ROV原理及在我国海洋石油工程中的应用

海洋石油的开发逐渐向深水区域发展，海上平台的建造，离不开导管架安装；的运输也需要铺设海底输油管线，因此，ROV作为一种新型实用的水下作业工具，的作用越发重要起来。深海石油天然气开采后在海洋石油工程项目中     

半潜式钻井平台发展及应用现状

<正>半潜式钻井平台作为发展较早的一种海洋油气开发工程装备,具有作业水深适用范围广、可变载荷大和波浪作用下运动响应小等优点,在深水和超深水油气勘探、开采等领域具有不可替代的作用。截至目前,全球半潜式钻井平台超过100座,主要活跃在欧洲北海、巴西及我国南海海域。此外,经过改装的半潜式钻井平台还在风电安装、海上发射以及军事等领域发挥着重要作用。     

深水平台钻井控制系统浅析

作为深海油气开采的重要组成部分,深水钻井控制系统对整个海洋油气资源的开发起到至关重要的作用。本文通过对国内已交付使用和在建的钻井平台控制系统进行比对研究,详细探讨了深水钻井控制系统的整体结构和接口。     

深水钢悬链线立管(SCR)安装分析研究

海管(立管)是海底生产系统和浮武装置之间的关键连接.随着海洋油气开发水深的不断增加,对海管(立管)自身以及辅助施工设备的性能都提出了更高要求,施工及正常作业的安全保证愈加重要.基于立管分析软件Orcaflex,针对项目中的SCR立管进行了安装分析,并依据规范进行应力、应变校核,可为深水安装分析及方案的确定提供一定的技术参考和理论支持.     

基于半数值方法的脐带缆拉弯能力曲线分析研究

水下生产系统脐带缆连接于水上主控站与海底管汇控制执行器之间,在安装和在位运行时脐带缆的受力情况复杂,其中工作内压下拉伸与弯曲组合形式的荷载是脐带缆承受的最显著工况之一,因此分析缆体截面拉-弯性能曲线有着重要的工程指导意义。文章首先采用理论公式对脐带缆内部关键构件钢管进行拉伸和弯曲荷载下受力分析并得到应力应变响应;同时构建脐带缆二维精细数值模型,考虑构件之间的相互作用与摩擦,分析径向外压与工作内压共同作用下缆体截面应力分布情况。通过提取钢管上热点应力并与理论结果相结合得到相应的拉—弯能力曲线。其结果同传统理论方法比较更加保守可信,可确保脐带缆在安装和在位工作时的安全运行。同时,为海洋工程管缆结构抗荷载能力设计提供一条可行途径。     

海底跨接管安装强度分析（英文）

A subsea flowline jumper(FJ) is a basic connected component for the wet oil tree, subsea pipeline and riser base, and it plays an irreplaceable role in the subsea production system. During the installation of FJ, collisions often happen between FJ and other equipment, which may cause serious damage. Besides, as the operating water depth increases, the demand for the installation equipments, such as the crane and winch, will increase. The research of deepwater FJ installation in China is still in the primary stage, thus an installation method for the deepwater FJ is proposed in this paper. Finite element models of a typical M-shaped FJ installation system are built to simulate the installation procedures. Analysis results show that the installation steps designed are feasible and valid for the deepwater FJ. In order to ensure the safety of the installation process, the collision-sensitive analysis for the FJ is conducted, and results show that it is necessary to set the pick up speed at a proper value, in order to avoid collision in the installation process. Besides, the mechanical characteristics of FJ during the installation are investigated under a range of environmental conditions and it is found that the maximum stress of the FJ always happens at its central position. The basic requirements for the installation equipment are also obtained through the analysis of the main installation steps.     

Installation strength analysis of subsea flowline jumpers

Subsea flowline jumper (FJ) is basic connection component for the wet oil tree, the subsea pipeline and the riser base, playing an irreplaceable role in the subsea production system. During the installation of FJ, collisions often happen between FJ and other equipment, which may cause serious damage. Besides, as the operating water depth increases, the demand for the installation equipments like the crane and winch will increase. The research of deepwater FJ installation in China is still in the primary stage, so an installation method for deepwater FJ is proposed in this paper. Finite element models of a typical M-shape FJ installation system were built to simulate the installation procedures. Analysis results showed that the installation steps designed for the FJ are feasible and valid for deepwater FJ. In order to ensure the safety of the installation process, the collision-sensitive analysis for the FJ was conducted, and results show that it is necessary to set the pick up speed at a proper value, in order to avoid collision in installation process. Besides, the mechanical characteristics of FJ during the installation were investigated under a range of environmental conditions and it was found that the maximum stress of the FJ always happens at its central position. The basic requirements for the installation equipment were also obtained through the analysis of the main installation steps.     

Efficient methods to mitigate SCR-induced walking of short subsea flowlines

Steel catenary riser is a long-established option for subsea projects in deep-water regions. Sustained pulling force of steel catenary risers on subsea flowlines in combination with cyclic thermal load throughout the system lifetime may lead to progressive global axial displacement of subsea pipelines which has been termed as ‘walking’. One of the challenges in the deep-water industry is long-term walking of subsea flowlines in a cumulative manner. Common practice methods for walking mitigation are quite expensive operations. State-of-the-art mitigation strategies are proposed in the paper by means of modifying pipe pieces before the installation operation. Bowed pipe pieces and miter joints are two recommended approaches for walking mitigation. The presented mitigation strategies are relatively cost-effective solutions for the pipe-walking challenge and they are able to considerably cease the potential cyclic walking. Comprehensive FE analyses in ABAQUS software are performed to evaluate the proposed deformed pipelines response subject to two loading conditions. Through-life integrity of the suggested pre-deformed pipeline is assessed in terms of effective axial force, local buckles and excessive axial strains. A comparison of the presented method with conventional techniques shows the effectiveness of the proposed configuration. The proposed methods can significantly reduce effective axial force throughout the subsea pipeline by means of artificially introduced deformations. The cumulative walking of the presented method is practically zero. In addition, the influence of combined triggering mechanisms to the walking phenomenon is assessed when the pipeline is located on a sloping seabed and it is subject to non-uniform thermal loads. A parametric study is performed to improve confidence in design and provide a reasonably practical technique with an optimal shape.     

Reliability-based design of subsea light weight pipeline against lateral stability

The application of non-metallic light weight pipeline (LWP) in subsea oil/gas transmission system is subject to subsea pipeline on-bottom stability problem because of their light weight. Additional weight required for the stabilization of subsea LWP is a critical item to consider when decreasing the cost of the pipeline system. This paper presents an effective approach to determine the additional weight by utilizing a reliability-based assessment of subsea LWP against on-bottom stability. In the approach, a dynamic non-linear finite element model (FEM), including a model of fluids-pipe-soil interaction for the subsea pipeline, is used to study the pipeline displacement response. In-place analysis of a flexible pipe is presented as an example of the authors' methodology. Results show that displacements are largely affected with and without considering the lift force. Additionally, the uncertainties of all parameters used in the model are considered. With 145 cases of FEM calculations being the samples, a response surface model (RSM) is developed to predict the pipeline lateral displacement using the software Design-Expert. Combing with the RSM equation, the Monte Carlo simulation method is employed to estimate the probability of exceeding pipeline stability. To calculate the reliability of LWP for different submerged weights, the method introduces a calibrated factor into the serviceability limit state (SLS) function. The proposed approach can be used to determine the additional weight required for the on-bottom stability of subsea pipelines while considering the uncertainties of all relevant parameters.     

深水水下结构物保温材料的研究与发展现状

深水水下结构物的绝热保温技术是深水油田开发的关键技术之一,我国目前对其研究不足,文中介绍了深水水下结构物保温的必要性、保温材料的研究与发展现状、保温材料涂覆安装方式等内容,为我国深水水下结构物的保温技术研究提供参考。     

A finite element model for unbonded flexible pipe under combined axisymmetric and bending loads

Flexible pipes are key equipment for offshore oil and gas production systems, conveying fluids between the platform and subsea wells. The structural arrangement of unbonded flexible pipes is quite complex, encompassing several layers with polymeric, metallic and textile materials. Different topologies and a large amount of intricate nonlinear contact interactions between and within their components, especially because of the relative stick-slip mechanism during bending, makes numerical analysis challenging. This paper presents an alternative three-dimensional nonlinear finite element model that describes the response of flexible pipes subjected to combined axisymmetric and bending loads. To simulate the response of a flexible pipe under axial tension or compression combined with uniform curvature, an equivalent thermal loading is employed on the external sheath, which is modelled as an orthotropic thermal expansion material with temperature-independent mechanical properties. To assess the feasibility of the proposed model, the bending moment versus curvature of the finite element solution is compared with experimental results obtained in literature and good agreements are found between them. Detailed finite element results such as contact pressures, armour wire slip displacements and friction, normal and transverse bending stresses are also shown and compared with available analytical models.     

基于S-Lay的水下在线管汇安装方法

结合南海某深水项目和S-Lay铺设方法以及OrcaFlex软件模拟结果,论述在线管汇安装技术及安装程序,讨论水下在线管汇安装施工时的注意事项。