Design of a cross-dipole array acoustic logging tool

When entering an anisotropic formation, a shear wave splits into a fast wave and a slow wave. Based on the principle of four-component cross-dipole acoustic wave measurement, the anisotropy of HTI （Horizontal Transverse Isotropy） formation can be determined. The method of calculating the fast and slow wave data when a shear wave propagates along the borehole axis in anisotropic formation was analyzed, and the implementation of a cross-dipole acoustic logging tool was demonstrated. The tool was composed of transmitter electronics, transmitter mandrel, acoustic isolator, receiver mandrel and main control electronics. Sonde, transmitter circuit, signal receiving and processing circuit, data acquisition system, system control circuit and telemetry interface circuit were presented and analyzed. The test model was used in production wells and standard wells in various areas and the four-component cross-dipole waves were acquired and processed. The waves had good signal-to-noise ratio and clear characteristics, and the fast and slow waveforms, processed slowness curves, anisotropy and fast shear wave azimuth well matched with each other.

Array processing-a new method to detect and correct errors on array resistivity logging tool measurements

In recent years more and more multi-array logging tools, such as the array induction and the array lateralog, are applied in place of conventional logging tools resulting in increased resolution, better radial and vertical sounding capability and other features. Multi-array logging tools acquire several times more individual measurements than conventional logging tools. In addition to new information contained in these data, there is a certain redundancy among the measurements. The sum of the measurements actually composes a large matrix. Providing the measurements are error-free, the elements of this matrix show certain consistencies. Taking advantage of these consistencies, an innovative method is developed to detect and correct errors in the array resistivity logging tool raw measurements, and evaluate the quality of the data. The method can be described in several steps. First, data consistency patterns are identified based on the physics of the measurements. Second, the measurements are compared against the consistency patterns for error and bad data detection. Third, the erroneous data are eliminated and the measurements are re-constructed according to the consistency patterns. Finally, the data quality is evaluated by comparing the raw measurements with the re-constructed measurements. The method can be applied to all array type logging tools, such as array induction tool and array resistivity tool. This paper describes the method and illustrates its application with the High Definition Lateral Log （HDLL, Baker Atlas） instrument. To demonstrate the efficiency of the method, several field examples are shown and discussed.

An ARM-based debugging system for multipole array acoustic logging tools

This paper presents a debugging system for multi-pole array acoustic logging （MPAL） tools. The debugging system proposed in this study can debug the MPAL tool system, sub-system and local electronics. In the test equipment, we have used principal and subordinate structures, and interconnected the host computer and the front-end machine via Ethernet. The front-end machine is based on the ARM7 （advanced reduced instruction set computing （RISC） machine） technique, the processor of which runs an embedded operating system, namely, uClinux OS. We have analyzed the system telecommunication, human-machine interface circuit, transmitter mandrel interface circuit, receiver mandrel interface circuit, and board-level test interface circuit. The software used in the system consists of the embedded front-computer software and the host application software. We have explained in detail the flow chart of the boot loader in the embedded front-computer software. The host application software is composed of four application subroutines, which match with the functional modules of the system hardware. A net communication program based on the server^client mode is implemented by means of socket programming and multi-thread programming. Test results indicate that the data transmission rate of the system is higher than 1 MB/s, which completely meets the current requirements of the data transmission rate between the tool system and the wireline telemetry device. Application of the debugging system, which includes multiple level test methods, shows that the proposed system can fully meet the test requirements of MPAL at various levels.

Design of Tubular Azimuth Gamma Ray Logging Tool

On the Gamma ray reception study, this paper presents the heavy metal shielding method, which is using C type heavy metal to shield Sodium iodide scintillation crystal. By rotating the drilling tools to scan and detect the gamma ray which are around the borehole wall formation, On study of angle measurement study, base on accelerometers and fluxgate sensors to design the algorithm which can confirm the detecting instrument measurement window position;Moreover, the paper also presents the Rock formation identification method, which is using changing tendency and sequencing of high side and low side gamma to decide the position of the drilling tool. Field experiments showed that the tool can effectively identify the reservoir and rock formation.

Simulation logging experiment and interpretation model of array production logging measurements in a horizontal well

The distributions of local velocity and local phase holdup along the radial direction of pipes are complicated because of gravity differentiation,and the distribution of fluid velocity fi eld changes along the gravity direction in horizontal wells.Therefore,measuring the mixture flow and water holdup is difficult,resulting in poor interpretation accuracy of the production logging output profile.In this paper,oil–water two-phase flow dynamic simulation logging experiments in horizontal oil–water two-phase fl ow simulation wells were conducted using the Multiple Array Production Suite,which comprises a capacitance array tool(CAT)and a spinner array tool(SAT),and then the response characteristics of SAT and CAT in diff erent fl ow rates and water cut production conditions were studied.According to the response characteristics of CAT in diff erent water holdup ranges,interpolation imaging along the wellbore section determines the water holdup distribution,and then,the oil–water two-phase velocity fi eld in the fl ow section was reconstructed on the basis of the fl ow section water holdup distribution and the logging value of SAT and combined with the rheological equation of viscous fl uid,and the calculation method of the oil–water partial phase fl ow rate in the fl ow section was proposed.This new approach was applied in the experiment data calculations,and the results are basically consistent with the experimental data.The total fl ow rate and water holdup from the calculation are in agreement with the set values in the experiment,suggesting that the method has high accuracy.

Influence of Logging Instrument Drag on Temperature Distribution in Horizontal Gas Wells

In order to clarify the influence of the instrument’s own drag on the temperature distribution in the horizontal gas wellbore in temperature logging.By constructing an indoor gas-liquid two-phase horizontal tube flow platform,the effects of the drag speed of the instrument on the temperature distribution in the wellbore were studied in the single-phase gas and gas-liquid two phases.In addition,during the process of instrument dragging,the influence of different perforation cluster opening methods and wellbore inclination on temperature distribution was also studied.The results show that the temperature fluctuation is reduced at higher drag speeds;Under a certain flow rate,the smaller the number of openings,the greater the influence of the instrument dragging inside the tube on the temperature distribution inside the tube;When the inclination angle is−5°,the drag of the instrument in the tube interferes greatly with the temperature distribution.When the inclination angle is 5°,the drag of the instrument in the tube has less interference with the temperature distribution.This study provides more reference for the future temperature calculation model of horizontal wellbore and has important research significance.

Application of Combined Production Logging Technology in Horizontal Wells

随着海上油气田开发的不断深化,水平井技术已在增储上产中起到了巨大作用,但也面临着出水及含水不断升高的问题。进行水平段储层生产测井,确定井下层内生产情况及储层动用情况,是后期控水稳产、措施挖潜的关键。水平井因井眼轨迹与储层平行、流体重力分异明显、上/下坡流共存等因素,常规居中测量中心流速的测井技术已不适用;同时,水平井为单层开采,剩余油饱和度分布无标准水层刻度,为生产层剩余油分布监测提出了挑战。提出了阵列式多相流测井仪组合(MAPS)和剩余油饱和度测井技术(RPM)的组合测井方式,通过水平段截面速度剖面、流体性质分布以及剩余油饱和度分布三者间的相互验证、综合解释的解决方案,取得了良好效果。

测井仪被动式热管理系统室温冷却研究

被动式热管理系统能使测井仪内部电子器件的温度在工作时间内不超过耐温指标,然而热管理系统优异的隔热性能导致测井仪需要较长时间冷却,才能投入下一次工作。为此,提出了一种针对测井仪的室温冷却方案。通过将电路骨架从保温瓶内抽出置于空气中实现快速冷却,同时设置芯片保护壳避免内部电子器件与空气直接接触,能够避免较高温差所产生的热应力及水蒸气液化对内部电子器件的损坏,实现快速冷却。模拟和试验验证了该方案的可行性,同时模拟探究了不同因素对冷却方案效果的影响,确定了最佳的冷却方案。研究结果表明,所提出的室温冷却方案可以解决测井仪被动式热管理系统冷却散热的问题,提高测井工作的效率。

井中方位纵波远探测: 理论、实验与现场应用

能够测量井外数十米地质构造距离和方位的远探测声波测井正成为一种重要的地球物理应用技术.1:1地层条件下井外含反射界面的远探测测量和分析为此技术提供了物理验证.本文首先利用虚源和柱面波展开理论推导了充液井孔中单极反射纵波方位接收声场的解析形式,通过模拟证明了单井的声波辐射和接收与双井之间的辐射和接收的等效性,在此基础上提出利用两口模型井来实现方位纵波远探测实验,即在测量井中放置多方位反射纵波接收声系,在另一口副井中放置单极子声源向测量井定向辐射纵波以等效来自井外地质体的反射波,依托实验室的模型井群进行井中方位纵波远探测实验研究.实验测量结果表明井中接收反射纵波的幅度和到时对井外反射体(定向辐射波)具有较好的方位灵敏度,可由此来实现井外地质异常体的精准定位.在理论与实验指导下自主设计研制了方位纵波远探测仪器样机并开展了现场井测试成功获得高信噪比的方位反射信号,充分验证了方位纵波远探测技术的准确性和有效性.

双向驱动井径测井仪推靠系统工作行为分析

针对单向驱动井径测井仪存在的启动响应慢、速度集中和初始运动冲击等问题,提出一种具有双向驱动特征的新型结构井径测井仪,并对其推靠系统(实现测量臂伸缩)双向驱动过程进行矢量化建模求解及工作行为分析(运动性能仿真、测量性能仿真)。首先进行双向驱动测井仪推靠系统物理建模和理论研究,以双驱动丝杠系统参数(速度、位移)为输入,采用复数矢量法对测井仪推靠系统运动性能参数(位移、速度、加速度)进行参数化表征;然后以实际双驱动推靠系统为对象进行实例分析,对其运动特性进行理论求解,得到推靠杆端口和推靠销钉的运动曲线,并对双驱动速度匹配特性进行研究;最后基于ADAMS进行测井仪工作行为分析,将仿真与理论结果进行对比,结果表明推靠系统仿真运动曲线与理论解析曲线具有较高的吻合度,证明了测井仪推靠系统矢量化建模求解的正确性。

取芯测压一体化测井仪研制及应用

为满足石油公司对地层流体和大体积岩芯的迫切需求,保证勘探出的地层流体和岩芯样品能充分满足物性化验分析的材料需求,获得各个岩层的岩性与含油性特征,并能直接测试地层压力和获取流体样品,研制出一种能够获取直径3.81 cm、长度5.5 cm的岩芯和地层真实流体样品的一体化组合测井仪。所研制的组合测井仪可以通过坐封PARKER密封地层,进行测压和取样作业,还可以在同一深度通过机械运动机构控制空心金刚石钻头钻入地层,利用取芯电机带动空心金刚石钻头高速旋转,获取与流体样品同层的大直径岩芯。该一体化测井仪的研制大幅度提高了作业效率,具有多种作业模式,可以大大提高岩芯和流体的收获率。该设备已在陆地油气井、疏松煤层、大斜度井、小井眼井等典型复杂井况中得到广泛应用,证明仪器地层适应能力强、安全可靠。

随钻超声阵列测井仪激励电路设计

通过随钻超声阵列测井仪获得的井壁反射特性可实时跟踪井身剖面,获取裂缝地层信息。随钻超声阵列测井仪激励电路的稳定性直接决定声波数据的质量。采用双极性脉冲激励的方式设计了一种随钻超声阵列测井仪激励电路,介绍了该电路的软、硬件设计,并进行了电路性能测试和实际测井试验。试验结果表明,该电路激励能量强,波形调节灵活,能够有效压制后续拖尾信号;同时测井信号清晰稳定,能够有效反映地层性质,为随钻阵列超声测井提供了技术参考。

仪器偏心对纵横波衰减影响的正演实验

近年来,水平井得到了越来越广泛的应用,在页岩气等非常规油气藏以及海上油气藏的勘探开发中发挥了至关重要的作用。但水平井测井在影响因素校正、资料处理和解释等方面尚存在诸多问题。针对仪器偏心对水平井声波测井响应影响的问题,开展了相关的物理模拟实验研究和数值模拟分析。提取了不同偏心率条件下的模式波的能量参数,分析了模式波能量随仪器偏心率的变化关系。结果表明,当仪器处于偏心状态时,模式波的能量均与仪器偏心率呈现类似负指数关系;仪器偏心率与模式波的能量衰减系数呈现S形曲线变化关系。研究结果有助于厘清仪器偏心对水平井声波测井响应的影响规律并为进一步开展仪器偏心对阵列声波测井响应影响校正方案研究提供指导。

测井仪电子短节通气主动冷却仿真与实验研究

被动式热管理系统有效延缓了测井仪电子短节的温升速率,但其优异的隔热性能同时导致作业完成后冷却缓慢,制约了快速转井的效率。该文提出了基于干燥冷空气单向对流换热的主动冷却方法,建立了流动、传热及相变耦合的瞬态主动冷却过程数值仿真模型,并开展了实验研究。仿真结果显示电路板最大降温速率为3.6℃/min,且储热模块在冷却3.5 h后完成液-固相变,恢复储热功能。实验结果表明,在以5 m/s的速度持续从小开口侧通入20℃干燥冷空气条件下,3.5 h即可将电子短节平均温度从190℃冷却至25℃,平均误差仅为9.4℃,验证了方案的可行性及仿真的准确性。研究结果表明,该研究所提出的通气主动冷却方法可以高效解决高温作业后测井仪电子短节散热缓慢的难题,并且基于该模型可设计自主调节的冷却工艺。

某随钻测井仪钻铤接头内螺纹裂纹失效分析

某随钻测井仪作业后发现钻铤接头内螺纹存在裂纹,造成该仪器无法作业;通过断口微观形貌分析、能谱分析、化学成分分析、硬度检验、金相组织分析来综合确定裂纹的产生机理并提出预防措施。分析结果表明:在腐蚀环境和复杂应力条件下,接头内螺纹裂纹始于齿顶侧壁的凹坑,开裂形式为穿晶解理断裂,兼具腐蚀疲劳断裂与应力腐蚀开裂;且钻铤材质沿晶界存在较多的沉淀,导致腐蚀敏感程度增加,也是裂纹产生机理之一。

一种基于改进CORDIC算法的阵列侧向测井仪信号发生电路

阵列侧向测井仪是目前测井工程中探测与分析复杂地质结构的一大利器。为实现5种不同探测深度的“阵列式”测井,仪器自身需要同时产生5种频率高精度正弦信号。本文对经典坐标旋转数字计算机(CORDIC)算法进行了改进与优化,改进后的算法计算量仅约为经典算法的1/3,大幅减小了DDS信号发生电路的输出时延。通过Modelsim软件仿真验证改进算法的可行性后,使用FPGA芯片编程,搭配DA/C与低通滤波电路,设计实现了一种基于DDS技术的阵列侧向测井仪信号发生电路。仪器外刻度模拟实验表明:搭载该信号发生电路的阵列侧向仪器能够在0.6Ω~100 kΩ电阻范围内保持良好的一致性,5种模式下电阻值实测误差均保持在10%以内,对于中低阻值模拟地层的测量精度达到了3%,较上一代阵列侧向仪器性能有明显提高。

测井仪器传热理论研究及仿真试验分析

为了保障石油开采向万米深层进发,提高测井仪器的耐温耐压指标,解决测井仪器电路热失效问题,针对测井仪器开展传热理论研究及仿真试验分析。根据测井仪器实际工况,通过仪器与井下流体的对流模型分析不同因素对平均对流换热系数的影响;针对直肋散热器构建传热模型,计算肋片散热效率,通过有限元方法求解测井仪器三维模型,并开展仪器高温试验,分析不同类型散热器对芯片温度的影响。结果表明,流体的平均对流换热系数与仪器上提速度正相关,可以通过调整井下流体成分的配比改变平均对流换热系数;测井仪器高温区域主要集中在芯片附近,应考虑将热量向仪器两端传递以提高散热效率;高温试验测试结果与散热器仿真结果一致,均说明弧形肋片散热器的散热效果最优。该研究可以为测井仪器热管理提供理论指导。

MGD无源磁导向工具隔热保护舱优化设计

目前测井仪器在175℃及以上高温环境下正常工作解决方案更注重隔热,通常使用真空保温瓶和多层隔热材料隔绝外部热量的进入,各学者主要通过理论公式和经验系数设计保温瓶,对保温瓶温度场数值模拟研究较少。为此,根据磁性探管的结构和保温瓶参数,结合温度场耦合分析了MGD无源磁导向工具温度场随时间变化的分布情况。分析结果表明:探管传感器在175℃左右的地层环境中需要工作8~10 h,此时上、下隔热体长度应为150、50 mm,上、下吸热体长度均为150 mm;增加吸热体体积可延长极限工作时间,应综合考虑工作时间、传感器适宜工作温度和隔热保护舱外形尺寸等因素合理确定吸热体体积。所得结论可为无源磁导向工具隔热保护舱的设计提供理论依据。

偶极声波测井仪常见故障及应对策略分析

随着经济的不断发展,社会生产对于石油的需求量越来越大,使得油田复杂油层的深度开发工作越来越受到重视。偶极声波测井仪作为开展石油勘探的一种重要设备,在复杂油层深度开发过程中拥有广阔的应用空间。由于油层勘探环境较为复杂,工作条件较为恶劣,偶极声波测井仪在使用过程中会遇到各种故障。深入分析偶极声波测井仪的常见故障,并提出有效的策略,对于保障其正常工作和提高勘探效率具有重要意义。基于此,以交叉偶极声波测井仪为例,分析使用过程中常见的故障类型,并给出相应的解决方案。

低频超声测井仪主控系统设计与实现

针对低频超声测井仪声波发射、数据采集及数据传输于一体的控制要求,设计了一种基于DSP+FPGA异构控制技术的新型主控系统。该系统使用DSP作为主控制器,通过CAN总线与井下电缆遥传通信,根据接收的指令产生控制时序,使用有限状态机完成工作流程控制,创新性地采用基于加权马氏距离的健康度评估方法评判仪器工作状态。使用FPGA作为从控制器,采用指令数据通道独立控制方法实时转发控制指令,同步声波激发与采集,实时接收声波数据。采用基于自定义并口双口RAM的协同通信机制完成DSP与FPGA之间的数据传输。采用差分传输技术实现与发射系统、采集系统之间的通信。测试表明:该主控系统通信误码率低,控制实时性高,状态评估准确,具备声波发射、数据采集及数据传输一体化控制能力,满足低频超声测井仪控制要求。