Strain-based design for buried pipelines subjected to landslides

Landslides are one of the key problems for stability analysis of pipelines in the western region of China where the geological conditions are extremely complicated. In order to offer a theoretical basis for the pipe-soil interaction, the general finite element program ABAQUS is used to analyze the distribution of pipe strain caused by landslide through which the pipeline passes. In this paper the Ramberg-Osgood constitutive equation is used to study the strain-based mechanical characteristics of pipelines. Different calculation schemas are designed by considering the change of spatial relationship between pipeline and landslide, and the change of D/t, diameter-thickness ratio of pipeline. The results indicate that the pipeline is primarily subjected to tension stress when the landslide crosses the pipeline perpendicularly, the pipe strain is a maximum along the central axis of the landslide, and reverse bending occurs on pipeline at both edges of the landslide. The pipeline is primarily subjected to friction force caused by the downward movement of the landslide, and the friction force is relatively small when the landslide is parallel to the pipeline. The pipe strain is in proportional to D/t, and this means decreasing D/t can help to improve security of pipelines subjected to the landslide.

Disaster reduction stick equipment: A method for monitoring and early warning of pipeline-landslide hazards

Oil and gas pipelines are of great importance in China,and pipeline security problems pose a serious threat to society and the environment.Pipeline safety has therefore become an integral part of the entire national economy.Landslides are the most harmful type of pipeline accident,and have directed increasing public attention to safety issues.Although some useful results have been obtained in the investigation and prevention of pipeline-landslide hazards,there remains a need for effective monitoring and early warning methods,especially when the complexity of pipeline-landslides is considered.Because oil and gas pipeline-landslides typically occur in the superficial soil layers,monitoring instruments must be easy to install and must cause minimal disturbance to the surrounding soil and pipeline.To address the particular characteristics of pipelinelandslides,we developed a multi-parameter integrated monitoring system called disaster reduction stick equipment.In this paper,we detail this monitoring and early warning system for pipeline-landslide hazards based on an on-site monitoring network and early warning algorithms.The functionality of our system was verified by its successful application to the Chongqing Loujiazhuang pipeline-landslide in China.The results presented here provide guidelines for the monitoring,early warning,and prevention of pipeline geological hazards.

Accuracy of pipeline blood glucose monitoring in patients with severe liver injury undergoing artificial liver support system treatment

Severe deterioration of liver function in patients can be characterized by coagulation disorders, jaundice, hepatic encephalopathy, ascites, and other symptoms. Severe liver injury can develop as acute liver failure, subacute liver failure, acute-on-chronic liver failure, or further worsening of end-stage liver disease [1].

Fiber Grating-Based Strain Sensor Array for Health Monitoring of Pipelines

Pipelines are one of the most important modern energy transportation methods,used especially for the transportation of certain dangerous energy media materials such as crude oil,natural gas,and chemical raw materials.New requirements have been put forward for the health monitoring and early security warning of pipelines because of the large-scale and complicated development trend of the pipe network system.To achieve an accurate assessment of the health conditions of pipeline infrastructure,obtaining as many precise operating parameters as possible,particularly at some critical parts of the pipeline,is necessary.Therefore,a novel type of fiber grating strain sensor array is proposed herein to monitor the pipeline hoop strain.The sensor utilizes fiber grating characteristics such as light weight,corrosion resistance,remote transmission,and strong environmental adaptability.The fiber containing the grating measurement points is implanted into the composite material to complete the sensitization encapsulation and protection of the bare fiber grating.The design of the sensor array fulfills the requirements for monitoring pipeline mass data,making it easy to form a pipeline health monitoring sensor network.The sensor sensitivity is researched by using a combination of theoretical and experimental analysis.A sensitivity test,as well as linearity and stability tests,are performed on the sensor.The experimental results show that the average sensitivity of the sensor is 14.86 pm/με,and the error from the theoretical calculation analysis value is 8.75%.Due to its high reliability,good linear response and long-term stability,and the ability to reflect the exact strain change of the outer wall of the pipeline,the designed sensor can support longterm online pipeline monitoring.The fiber grating sensor array network has successfully realized the monitoring of the pipeline’s internal operation by using external strain changes.In addition to the performance benefits,there are other merits associated with the applicability of the sensor namely simple structure,compact size,manufacturing ease,and exterior installation ease.

Analysis of the displacements of pipeline overpasses based on geodetic monitoring results

There are many approaches to address geospatial monitoring of pipeline overpasses,among which the most widespread methods are terrestrial laser scanning and total station measurements.However,there is a problem in comparing the geospatial monitoring data collected by different methods in different epochs.The main task of this work is to find the correspondence between points in different epochs.The total station measurements are carried out in specific discrete points of the pipeline overpass.In contrast,terrestrial laser scanning allows the collection of the whole data set without fixing specific point co-ordinates.In order to compare different data in different epochs,it is necessary to select a relevant presentation of the monitoring results(reference model)and specify appropriate criteria for quality inspection.In general,a pipeline can be presented as a spatial curve.In this study,two types of reference models are considered:cubic splines and Bezier curves.These models are examined for the monitoring of two gas pipeline overpasses.The first measurement epoch is accomplished by the terrestrial laser scanning,and the second measurement epoch is completed by the total station.The reference models are simulated by Matlab coding.The preliminary accuracy of ground laser scanning and total station mea-surement is selected as the criterion of quality inspection.The simulation and comparison results provide the evidence that the correct selection of reference model is a crucial component of successful geospatial monitoring.The results show that the Hermite splines are effective in the comparison of different data sets.These splines present the interpolation accuracy compatible with measurement accuracy,i.e.,15-20 mm for spatial displacement determination.

A Dual-Parameter Fusion Distributed Optical Fiber Sensor System for Oil and Gas Pipeline Monitoring

For oil and gas pipeline monitoring applications, this paper proposed a dual-parameter fusion distributed fiber optic sensor system that enables distributed temperature and distributed vibration measurements in a single fiber. Through the fiber-scattering spectrum time domain detection combined with coded pulse sequence and Raman scattering spectrum is obtained, which realizes high-resolution temperature measurement and wide-band vibrational wave measurement. The experimental results show that, on 10 km optical fiber measurement, temperature resolution up to 0.1?C and vibration response frequency range 20 Hz - 5 kHz. This sensing system achieves temperature and vibration dual-parameter measurements with fiber optics, greatly simplifying the system and facilitating installation and it can be widely used in oil and gas pipeline monitoring.

Vertical Displacement Monitoring and Safety Evaluation of Oil Pipelines in Permafrost Region

This paper presents the development of a liquid pressure based automatic monitoring device of the vertical displacement of oil pipeline that has good applicability to the extreme cold conditions of the permafrost region and is capable of automatic collection and transmission of monitoring data. The effectiveness of the device has been verified using total station measurement method and the results show that the device can intuitively indicate the vertical displacement of the pipe under the harmful influence of frost heaving and thaw settlement. According to the monitoring data, safety evaluation of the pipe during the monitoring period is carried out using stress-based design criteria and strain-based design criteria respectively. The analytic results with stress-based design criteria show that the pipe may be in a dangerous state while the results with strain-based design criteria show that the pipe is in a safe state. The design method with strain-based criteria is complementary to the design method with stress-based criteria. Separate use of either method is not recommended.

Real-time Monitoring of Subsea Gas Pipelines,Offshore Platforms,and Ship Inspection Scores Using an Automatic Identification System

The aim of this research is to develop an algorithm and application that can perform real-time monitoring of the safety operation of offshore platforms and subsea gas pipelines as well as determine the need for ship inspection using data obtained from automatic identification system(AIS).The research also focuses on the integration of shipping database,AIS data,and others to develop a prototype for designing a real-time monitoring system of offshore platforms and pipelines.A simple concept is used in the development of this prototype,which is achieved by using an overlaying map that outlines the coordinates of the offshore platform and subsea gas pipeline with the ship’s coordinates(longitude/latitude)as detected by AIS.Using such information,we can then build an early warning system(EWS)relayed through short message service(SMS),email,or other means when the ship enters the restricted and exclusion zone of platforms and pipelines.The ship inspection system is developed by combining several attributes.Then,decision analysis software is employed to prioritize the vessel’s four attributes,including ship age,ship type,classification,and flag state.Results show that the EWS can increase the safety level of offshore platforms and pipelines,as well as the efficient use of patrol boats in monitoring the safety of the facilities.Meanwhile,ship inspection enables the port to prioritize the ship to be inspected in accordance with the priority ranking inspection score.

PIPELINE软件在气田集输实时监控中的应用

PIPELINE软件是一种离线或者在线的集输管网仿真模拟计算软件,不但可以用来测试和评价输气管道的设计或进行实际操作参数的设置,还能与气田集输实时监控系统进行有机结合,为集输管网运行提供辅助专家诊断分析。以大牛地气田集输生产实际为例,进行管网水力、热力计算,天然气调峰正常工况分析和用户中断用气工况模拟分析,结果表明,该仿真模拟软件和实时监控系统有机结合,改变了气田根据人工计算或凭经验来预测天然气集输管网的运行情况和调峰的现状,不但降低了劳动强度,而且使预测效果得到了根本性提升,排除了管网运行管理的安全隐患。PIPELINE软件不仅方便了管网的运营管理,还避免了生产调度上的盲目性,为科学地管理气田集输管网系统提供了专家式的理论指导。

An Overview of Structural Design,Analysis and Common Monitoring Technologies for Floating Platform and Flexible Cable and Riser

Offshore oil and gas development plays an important part in the global energy sector.Offshore platforms and flexible pipes are the key equipments in the whole offshore oil and gas development system.Because of the randomness and uncertainty of wave and current loads in the ocean environment,the structural design and mechanical analysis of the marine equipment can be highly complicated.Therefore,this paper reviews the recent works of the theoretical model,numerical simulation,and experimental test in three research areas:hydrodynamic analysis of offshore platforms,structural mechanics analysis of flexible pipe and cable,and monitoring technology of offshore floating structures under marine loads.By analyzing their main research methods and key technical difficulties,this paper provides theoretical basis and technical support for the reliability engineering application of offshore platforms and flexible pipelines.Also,China is relatively backward in the design of marine floating platform,the design,analysis and testing of flexible pipeline and cable,as well as the marine equipment prototype monitoring technology research.Calling for breakthroughs at the earliest possible stage in the above fields,prime research should be focused on and strategic planning should be made to deal with“key areas and stranglehold problems”.It is of great significance for the development of China's deep-sea energy and resource development of independent technology and on time to achieve the“carbon peak”national strategic objectives.

基于NB-IoT技术的天然气管道泄漏监测系统

为了对天然气管道运行情况进行实时监测,在发生泄漏时能够及时做出反应,设计了基于NBIoT技术的天然气管道泄漏监测系统。系统利用压力变送器、DHT11温湿度传感器和GPS/北斗定位系统分别对管道的内部压力、设备周围的温湿度和经纬度位置进行采集,将采集的数据通过STM32控制NBIoT物联网模块上传至OneNET物联网云平台,最终通过云平台对天然气管道进行实时监测。实验表明:该系统能够对天然气管道的数据进行实时上传,能够通过云平台进行天然气管道状态的实时监测。

基于VMD-HT和深度学习的流噪环境腐蚀损伤声发射识别模型

对在役管道进行腐蚀声发射监测的过程中,管内介质流动产生的噪声同样会被传感器接收,导致腐蚀信号被覆盖从而引发误判。针对这一问题,提出了一种基于变分模态分解(VMD)、希尔伯特变换(HT)和深度双向门限循环单元神经网络(BiGRU)的流噪环境腐蚀损伤声发射识别模型。该模型能够将原始信号自适应地转化成多个本征模态分量,并提取各分量的瞬时频率及谱熵构建多维时序特征矩阵,进而建立原始信号与多维特征之间的映射关系。为验证该方法的有效性,对在役管道进行腐蚀声发射监测试验。结果表明,所提模型在流噪环境下具有良好的鲁棒性,监测数据的识别准确率达96.3%,可作为一种解决在役管道腐蚀声发射监测的新方案。

输氢管道完整性管理技术研究进展

管道输氢被认为是当前效率最高、经济性最好的大规模输氢方式。围绕输氢管道管材的相容性、氢气的泄漏与监测、完整性管理方法与相关规范缺失等关键问题,对目前相关研究进行了归纳与总结。结果表明:典型管道钢材在高压临氢环境下产生氢致失效的机理尚未明悉,需探明临氢环境下不同等级钢材力学性能的劣化规律,并分析钢材氢脆敏感性的影响因素;输氢管道更易发生泄漏,应重点明确输氢管道及相关设备产生泄漏的具体原因,完善氢气泄漏监测技术;目前输氢管道完整性管理方法缺失,需重点考虑氢气对输氢管道完整性管理中风险评价和完整性评价的影响,完善输氢管道完整性管理方法;结合现有输氢管道规范的相关内容,为输氢管道完整性管理提供支撑,推进输氢管道完整性管理标准与规范的制定。相关结论可以为输氢管道完整性管理技术的发展提供参考。

管道工程穿越既有轨道交通安全评估与监测实例分析

由于管道工程临近地铁保护区的项目不断增加,安全评估和专项监测的应用非常必要。论文以某出水管工程涉及轨道交通5号线为例,设计了专项监测方案,重点分析了管道施工影响既有地铁车站结构安全评估预测与实测的监测变形,验证了安全评估的预测值与实际监测数据的符合性。

油气管道事故致因和监测模拟研究现状与展望

随着国家经济与民生工程的高质量发展,石油与天然气成为我国经济、政治、军事安全的重要的战略储备资源,是全面发展和建设现代化的基础和动力。其中以输送石油和天然气为重任的油气管道更是被誉为国家能源发展的大动脉。由于油气产品易燃、易爆,油气管道运营过程中存在风险较高,且基础设施关键零部件较多、系统复杂,国内外油气管道失效事故也屡有发生,我国在油气管道防控方面的研究仍缺乏系统性。因此,笔者系统梳理了国内外事故致因理论、泄漏监测技术和数值模拟研究的发展趋势,在此基础上构建系统事故致因分析模型和全生命周期检测模拟所面临的挑战,为完善我国油气管道运营安全提供参考。

智慧系统在液体散货码头装卸工艺中的应用

结合智慧港口应用热点和当前行业发展现状,以某液体散货码头为例,针对码头装卸工艺中智慧系统的应用,从智能装卸臂、在线腐蚀监测、在线自动取样、管道无人巡检等系统进行多角度的分析,提出可在当前液体散货码头装卸工艺中落实的智慧系统模块的应用方案。该方案可减少现场工人的工作量,通过数据赋能提升码头运营、管理等作业效率,提高港口管理的信息化、精准化,并可为类似工程提供参考。

海洋CO_(2)管道输送技术现状与展望

管道输送是经济高效的CO_(2)运输方式,海洋CO_(2)运输是离岸碳捕集、利用与封存(CCUS)产业链的关键环节和规模化开展离岸CCUS工程建设所需的核心技术。本文明晰了我国实施离岸CCUS的优势、典型海洋碳运输情境和海洋CO_(2)运输方式,剖析了国内外海洋CO_(2)管道输送的技术与工程概况;从CO_(2)流体相态及流动安全,沿程腐蚀风险评估、监测及预警,CO_(2)泄漏实时监测技术,高压CO_(2)泄放及对环境的影响等方面梳理了海洋CO_(2)管道输送工艺技术现状;从CO_(2)管道材料断裂行为及止裂措施、高耐蚀及密封材料、碳钢管道长寿命运行的关键腐蚀控制技术、注采井筒的腐蚀风险评估等方面梳理了海洋CO_(2)管道材料技术现状。研究认为,加快发展适应海洋CO_(2)管道输送复杂工况的材料体系、全流程CO_(2)管道的智慧管理与数字孪生技术、海底CO_(2)管道全生命周期运行关键技术、在役海底管道改输评估与保障技术,采取加快推动我国近海碳封存CO_(2)管网规划、拓展和深化跨行业/跨机构合作模式创新、系统建设海陆统筹的标准体系、引导专业化技术服务企业深度参与海底CO_(2)管网建设等举措,促进我国海洋CO_(2)管道输送体系高质量建设。

基于在线监测的核电厂主管道评定技术及软件开发

研究了基于运行参数在线监测的主管道断裂评定方法,建立了由热电势测试材料冲击功、裂纹撕裂断裂韧度预测和在线含缺陷管道断裂评定的成套技术方案,开发了专用的主管道断裂评定软件,并验证了某工况下使用该软件的计算结果与原设计要求偏差小于3%。

基于正负区间统计分析的信号趋势项自适应消除方法

趋势项的存在会严重影响信号异常检测方法的准确性,因此需要在信号预处理过程中进行消除。高通滤波法是一种简单且有效的趋势项去除方法,应用最为广泛,但其参数选择基于经验,无法实现实时最优,因此方法的鲁棒性和泛化性差。以高通滤波法为基础,首先提出了信号正负区间统计分布曲线的概念,并基于这一概念引出了趋势项判断准则。在此基础上,设计了高通滤波器截止频率的实时优化选择方法以实现信号趋势的自适应消除,并对所提方法的影响要素进行分析。结合实际应用问题改进了算法,提高了迭代收敛速度,减少了计算量。最终利用石油管道泄漏监测问题中的压力信号数据证明了所提方法可以获得实时最优的滤波效果,实现趋势项的消除,且预设参数简单,算法计算量小。

供水管网漏损控制方法与应用成效分析

随着经济社会发展,城镇化进程加快,水资源供需矛盾短缺日趋严重,而城市供水管网漏损,是目前困扰节水的难题之一,供水管网漏损控制已成为“十四五”城市供水行业的重点工作之一。文章简要介绍了供水管网漏损的原因和主要控制方法。重点结合水司自身特点,分析了实际工程应用成效,主要包括:推进独立计量区(DMA)进行的夜间最小流量监控;开展日常巡检及周期性检漏;定期开展水表轮换;改造老旧管网;布设管网压力监测点;加装水池水箱远程监控。而通过各种不同控制手段的结合使用,有效地控制了管网漏损,2023年综合漏损率降低为10%,研究成果以期为各水司供水管网的漏损控制提供指导和借鉴。