NONLINEAR DYNAMICS RESPONSE OF CASING PIPE UNDER COMBINED WAVE-CURRENT

The vortex-induced nonlinear vibration of casing pipes in the deep water was studied considering the loads of current and combined wave-current. The vortex-induced vibration equation of a casing pipe was set up considering the beam mode and Morison’s nonlinear fluid loads as well as the vortex-excited loads. The approach of calculating vortex-excited nonlinear vibration by Galerkin’s method was proposed. The natural vibration frequencies and modes were obtained, and the response including primary resonance induced by current and the composite resonance under combined wave-current for the 170 m long casing pipe in the 160m depth of water were investigated. The results show that the dynamics response of casing pipe obviously increases, and the complicated response behaviors of casing pipe are described under combined wave-current.

NONLINEAR DYNAMICS RESPONSE OF CASING PIPE UNDER COMBINED WAVE-CURRENT

The vortex-induced nonlinear vibration of casing pipes in the deep water was studied considering the loads of current and combined wave-current. The vortex-induced vibration equation of a casing pipe was set up considering the beam mode and Morison＇s nonlinear fluid loads as well as the vortex-excited loads. The approach of calculating vortex-excited nonlinear vibration by Galerkin＇s method was proposed. The natural vibration frequencies and modes were obtained, and the response including primary resonance induced by current and the composite resonance under combined wave-current for the 170 m long casing pipe in the 160 m depth of water were investigated. The results show that the dynamics response of casing pipe obviously increases, and the complicated response behaviors of casing pipe are described under combined wavecurrent.

Case Analysis of a Pump-Driven Heat Pipe Heat Recovery Ventilator in an Existing Experiment Building

The building energy consumption is an important part among the total society energy consumption,in which the energy consumption for air conditioning occupies almost 70%.The energy consumption of the air conditioning system for fresh air handling can be saved effectively when the exhaust air energy could be recovered to preheat or precool the fresh air.Considering the install locations requirements on field,the pump-driven heat pipes(PHP)were developed as heat recovery ventilators(HRVs)and used in an existing experiment building in Beijing Urban.The thermal performance of the PHP HRVs was tested in real operation time periods under winter running mode.Both the power and heat consumption of the modular air handling units with and without HRVs were monitored and obtained,as well as the hourly power and heat consumption.The energy savings of HRVs were analyzed.The results indicate that the PHP HRVs can work steadily and meet the energy recovery need well.The temperature effectiveness of the HRVs can be kept from 60%to 70%.The test total energy saving rate was 24.48%,and the average hourly heat consumption reduced by 28.54%.The daily energy consumption can be saved by 118 kWh,and the energy savings can reach to 9440 kWh for a whole winter.

Analysis of Drill Pipe＇s Effect on Casing

Frictional wear of inner walls of drill pipe and casing is produced by rotational advance of drill pipe in the casing due to the joint effect of drilling fluid, temperature and contact load during drilling, among which the main wear is on the drill string. With development of drilling technology, deep well, ultradeep well, high angle well, directional well, extended reach well and horizontal well are taking more and more proportion. Meanwhile, the problem of serious frictional wear between drill pipe and casing are becoming more significant due to long time of drilling, high probability of dogleg severity, high contact normal stress between drill pipe and casing etc. Tool sticking may also occur due to large frictional resistance. Therefore, higher requirements are made on the study of how to predict and prevent the wear of drill pipe and casing during drilling. The residual strength of the worn casing is also studied by analysis of the law of drill pipe＇s effect on the casing wear in this paper.

Progress and future prospects of application technology for tubing and casing

The main failure modes of tubing and casing in current service conditions are represented in this study.The progress of the tubing and casing application technology and the problems that should be focused on during application are introduced,with special attention paid to the reliability of the pipe string design and the connection sealing properties.The necessary work that should be undertaken in future research is also summarized.

Theoretical Prediction of the Bending Stiffness of Reinforced Thermoplastic Pipes Using a Homogenization Method

The accurate prediction of bending stiffness is important to analyze the buckling and vibration behavior of reinforced thermoplastic pipes(RTPs)in practical ocean engineering.In this study,a theoretical method in which the constitutive relationships between orthotropic and isotropic materials are unified under the global cylindrical coordinate system is proposed to predict the bending stiffness of RTPs.Then,the homogenization assumption is used to replace the multilayered cross-sections of RTPs with homogenized ones.Different from present studies,the pure bending case of homogenized RTPs is analyzed,considering homogenized RTPs as hollow cylindrical beams instead of using the stress functions proposed by Lekhnitskii.Therefore,the bending stiffness of RTPs can be determined by solving the homogenized axial elastic moduli and moment of inertia of cross sections.Compared with the existing theoretical method,the homogenization method is more practical,universal,and computationally stable.Meanwhile,the pure bending case of RTPs was simulated to verify the homogenization method via conducting ABAQUS Explicit quasi-static analyses.Compared with the numerical and existing theoretical methods,the homogenization method more accurately predicts the bending stiffness and stress field.The stress field of RTPs and the effect of winding angles are also discussed.

The current situation and prospect of oil steel pipe in China

The oil steel pipe in the petroleum industry is very important for its high price, large consumption volume and great effect on the development of petroleum industry. The oil steel pipe mainly includes oil well pipe (drill pipe, drill collar, casing and tubing etc.) and oil-gas transportation pipe. This paper is an attempt to make a comprehensive review on the current situation and prospect of the oil steel pipe in China, presenting the past , today and future of the China oil pipe. The first section is a historical review of the China oil pipe. The developing course and progress of the oil steel pipe products are presented. The second section is about the current situation of the China oil pipe. The general situation of the China’s steel pipe corporation and their products types, capability, etc. is introduced. The third section is about the prospect of the China oil pipe. This part mainly describes the new product research and development in China steel pipe corporations, which are facing more and more strict technical requirements of the petroleum industry in oil pipe, and reveals the prosperity of China’s steel pipe corporations.

井中永置式套管外三分量光纤MEMS地震检波器研究

针对非常规油气井套管外永置式微振动监测,研制了一种基于光纤法布里帕罗(F-P)干涉原理和微机电(MEMS)技术的三分量光纤MEMS地震检波器,将微地震信号转化为F-P腔长的变化,通过超快光谱探测技术和动态白光干涉解调技术实现高速解调。设计并理论仿真了μm/g量级的高灵敏度MEMS加速度芯片,突破大深度双面套刻工艺完成芯片样品制造。采用高集成度小型化结构设计、无胶封装工艺设计和陶瓷微加工工艺实现25 mm微型外径,满足套管外永置式安装要求,提高了高温检测精度。在实验室完成了检波器与标准电学加速度计的性能对比测试,结果表明:检波器可耐受175 MPa高压和180℃高温,灵敏度分别为1.2382,1.2590,1.0862μm/g,工作频带为0~350 Hz,量程为±5 g,线性度误差<0.01%,抗横向串扰能力<5%。研制的检波器耐高温高压、尺寸小巧、灵敏度高、线性度良好,在非常规油气井储层压裂改造和采油气生产过程中,永置式套管外的三分量光纤MEMS地震检波器可以发挥重要的监测作用。

国产超声兰姆波测井仪在套管回收中的应用

在开发油气田进入生产末期时为了节约成本会将未被水泥固结的套管进行回收,为了确定回收套管的起始深度需要进行相应的测量得到套后水泥的分布情况。以往常常采用外方的测井仪器作业,导致费用高昂。中海油服在近年推出了具有完全自主知识产权的超声兰姆波成像测井仪(简称UCCS),首次在东海区域成功作业帮助油公司判断了套后水泥环分布状态,进一步指导了套管切割作业。

基于厚壁圆筒理论的袖阀管注浆开环压力计算方法及影响因素分析

目的袖阀管注浆技术已广泛应用于地层加固、路基病害治理、地铁站渗漏水处治等众多工程领域,然而袖阀管注浆的关键技术—开环压力的确定问题目前尚未有效解决。为解决此问题,方法基于厚壁圆筒理论模型,提出任意倾斜状态下袖阀管出浆口地层应力计算方法,结合第四强度准则,建立考虑多因素综合影响的袖阀管注浆开环压力理论计算公式,并进行开环压力影响因素分析。结果结果表明,袖阀管注浆开环压力随套壳料抗压强度、套壳料与土体泊松比比值、注浆深度、地层最小与最大水平主应力比值的增大而增大,随着套壳料内外半径比、套壳料与土体弹性模量比的增大而减小。套壳料抗压强度、套壳料内外半径比、注浆深度和注浆钻孔方向对开环压力的影响较显著。注浆钻孔方向对开环压力影响较大,α一定时,开环压力随β增大而减小;β一定时,开环压力随α增大而增大。将本文建立的袖阀管注浆开环压力计算公式应用于新建大冶北至阳新铁路DK107+105框架顶进涵工程,并与现有开环压力计算方法进行对比,利用本文方法计算得到的开环压力值更接近现场实测范围,并优于现有计算方法。结论研究结果可为袖阀管注浆理论发展和现场应用提供支持。

近千米大直径穿强厚含水层降温管井钻孔设计

制冷降温是深部矿井热害防治的有效技术手段。以核桃峪矿井制冷降温系统建设工程为背景,针对降温管井钻孔深度大,穿过洛河组巨厚强含水层,长距离输送冷媒保冷等技术难题,在分析工程及水文地质条件基础上,确定管井钻孔两次开孔分段设计参数;通过调研管路保冷材料性能,提出复合钢管、静态空气、玻璃微珠增强水泥、钢基复合保温套管四种保冷方法条件下基岩段护壁管设计方案;综合考虑保冷效果、固井可靠性、施工难度等因素,优选工作管采用钢基复合保温套管;并根据套管受力计算,校验护壁管规格参数。工程实施效果表明,井上下降温管始末端温度损失约1℃,可以满足冷媒长距离输送冷量损失要求,对于类似工程具有借鉴价值。

贵州省岩风阡铝土矿钻探施工工艺研究

贵州岩风阡铝土矿项目实施中钻遇硅质岩层,在钻进过程中产生的钻屑在钻井液漏失孔段不容易排出,易发生埋钻、卡钻、无芯等现象。通过优化钻孔结构、合理选择钻进参数,采用跟管钻进配合绳索取心工艺,有效解决了穿越溶洞的护壁难题,大大提高了钻遇溶洞成孔率。采用聚合物凝胶护壁堵漏减少了破碎地层掉块卡钻事故的发生。提高了钻进效率,节约了钻探成本。采用长套管穿越溶洞,降低了报废工作量,提高了工作进度。通过一系列技术措施的实施,如期完成了项目施工任务。本文对该矿区的施工经验进行了总结,希望为类似矿区钻探施工起到借鉴作用。

X65级双层海管外管全自动焊工艺研究

基于STT封底和全自动FCAW-G填充盖面焊接,开发了一种适用于双层海管外管全自动焊工艺,通过宏观形貌观察、力学性能测试等手段验证自动焊工艺下的海管焊接接头的可靠性,满足DNV OS F101:2017《海底管线系统》标准要求,可应用于X65碳素钢海管外管的焊接施工。

塔里木油田套管回接治理套损工艺的革新与应用

塔里木油田HD油田进入开发中后期,套损逐渐呈现出多点长井段特征,传统挤堵工艺经实际作业验证已不适于多点长井段套损井的治理。为解决上述问题,从井筒实际情况出发,探索出回接非常规套管套损治理工艺,并在HDA井成功应用,该次作业首次采用在7寸套管内回接5-1/2寸无接箍套管至井口,并成功实施小间隙两层套管间固井,探索出多点长井段套损治理新工艺。后续已累计回接4口套损井,治理后堵水增油效果显著,累计增油超2 000 t。

三种直推式双侧向套管内测井研究及辅助QC应用

近年来,工区内塔河、顺北等以超深层碳酸盐岩为主要目的层的油气田,存储式测井应用逐年增加。上、下测进套管双侧向仪器都在测井档工作,曲线较完整。以往文献资料主要论述了双侧向测井工艺、仪器故障等,对简单的套管内测井数值研究内容涉及较少,根据电缆测井规范和仪器原理,通过用双侧向的电压比电流来拟合名义电阻率,进行套管内电阻率测井数值研究,对井下仪器工作的稳定性和曲线质量做出一些辅助的评价。从工区内三种常见的直推式双侧向仪器特点入手,选取近两年来34口井测井资料,拟合并分析了三种直推式双侧向的套管测井值形态和数值特点,列举了三个名义电阻率测井应用实例,提出了辅助QC方面的建议。对同行有借鉴意义。

汽轮机蒸汽管道与阀门及汽缸外缸外表面传热系数的计算模型和计算方法

构建了汽轮机蒸汽管道、主汽调节阀与汽缸外缸的外表面传热系数计算模型与计算方法。给出了汽轮机蒸汽管道、主汽调节阀、高压外缸、中压外缸与低压外缸的内表面传热系数以及保温结构外表面与低压外缸外表面的复合传热系数计算公式。建立了汽轮机蒸汽管道、高压外缸与中压外缸的金属内层壁与保温结构外层壁的双层圆筒壁、主汽调节阀金属内层壁与保温结构外层壁的双层球壁以及低压外缸单层圆筒壁的传热过程计算模型。考虑到金属内层壁内表面温度与外表面温度和保温结构外层壁外表面温度均为待定温度,采用迭代法确定这些汽轮机部件的表面温度、传热过程的传热系数与热流密度。完成了汽轮机蒸汽管道、主汽调节阀、高压外缸、中压外缸与低压外缸的外表面传热系数计算分析的应用实例,得出了这些汽轮机部件传热过程金属内层壁外表面的传热系数、热流密度与等效表面传热系数的计算结果,为这些汽轮机部件温度场与应力场的有限元数值计算提供了传热边界条件。

南宁盆地特殊地层静压随钻跟管桩承载特性现场试验及数值模拟研究

随钻跟管桩(简称DPC桩)是一种钻孔-沉桩-排土同步进行的无泥浆排放的节能环保型大直径新型非挤土PHC管桩。为探究随钻跟管桩在南宁盆地特殊地层的适应性及承载特性,开展了现场原位试验、数值模拟分析,分析了这种新桩型的承载性能优势、桩侧摩阻力分布特征、荷载传递特性。得出如下结论:原位静载试验中,各试验桩荷载-沉降曲线呈缓变型,且承载性能均满足设计要求,桩身回弹率较高,各试验桩仍具有较大的承载潜力;桩身轴力沿桩身近似呈线性递减,桩端荷载约占桩顶荷载的20%~30%,桩侧摩阻力分担了70%~80%的桩顶荷载;桩侧摩阻力沿桩身深度分布均表现出了两头小、中间大的规律,随着荷载增加,桩侧摩阻力逐渐下移。可见,该桩型在南宁盆地特殊地层具有良好的适应性。

浆液套管增强沿空掘进煤柱稳定性数值模拟研究

为解决采动作用下沿空掘进巷道一侧窄煤柱变形等问题,现场采取浆液充填套管加固煤柱底板以改善煤柱的稳定性。采用数值模拟分析浆液充填套管对底板岩体变形的控制作用机制。数值计算结果显示,在横断面方向煤柱两侧测点变形高、中间测点变形低,近采空侧的测点变形大于近巷道侧测点变形。煤柱基底变形不一致会导致煤柱受力不均,顶板荷载作用下煤柱变形形态更加复杂。施加浆液充填套管后,煤柱基底测点的变形量减小。巷道侧煤柱底板测点变形减少20.5%,大于采空区一侧的改善效果19.2%。采动作用下随着深度增加底板岩层变形逐渐减小,施加浆液充填套管后底板岩层变形减小。对类似矿井的沿空掘进巷道一侧煤柱变形研究有指导意义。

建筑管道排烟系统设计要点探究

通过对建筑管道排烟系统设计的要点进行探究,包括建筑特点和使用需求分析、系统设计和计算方法应用、施工过程中的注意事项、设备安装和连接方式、烟气产生量和速度的计算、风机选型和功率计算、定期检查和清洁、故障排除和维修方法、系统更新和升级的考虑等内容。通过案例分析,将理论知识与实际工程相结合,深入探讨了建筑管道排烟系统设计的关键要点。

老旧城区排水管道地箭式微顶管技术应用研究——以武汉市老城区改造为例

以武汉市历史风貌区老旧城区排水改造工程为背景,对复杂地质下地箭式微型顶管施工进行分析研究,介绍了微型顶管技术的工艺原理,重点阐述了微型顶管技术在城市排水改造工程中的施工工艺及控制措施,提出了高压旋喷桩止水帷幕+洞口橡胶止水装置以及触变泥浆智能注浆系统对流沙、涌泥的防治方法,切实解决了传统开槽法排水管道施工的不足,为类似工程施工提供借鉴。