基于小波包最优处理算法的近钻头电阻率随钻测量装置

岩石的电阻率与岩性、储油物性和含油性有着密切的关系。基于小波包最优处理算法的近钻头电阻率随钻测量装置,由于采用随钻的测量方式,能实时在第一时间测量到地层电阻率信息。并且通过小波包最优小波树信号提取等算法,可用来对侧向电阻率、钻头电阻率以及方位电阻率进行高精度测量。     

MEMS随钻惯性测量单元设计与实现

针对基于磁通门随钻测量的局限性与惯性技术测量方案优势,结合随钻测量过程中强冲击、震动等环境特点,设计并实现了基于MEMS陀螺仪和加速度计的随钻惯性测量单元。对系统测试发现MEMS陀螺随机漂移误差较大,为此,采用改进时间序列分析法对巴特沃斯低通滤波后信号随机漂移进行建模。与传统时间序列方法建模相比,新方法降低了模型预测误差,滤除MEMS陀螺随机漂移误差更为明显,且在提高精度的同时保证了数据处理实时性。结果表明:系统能够实现近钻头安装,在钻进的同时完成相应参数的测量,达到设计要求。     

矿用泥浆脉冲无线随钻测量装置及其应用

针对采用中心通缆式钻杆作为信号传输通道的有线随钻测量装置存在的钻杆结构复杂、机械性能受限、抗干扰能力差等问题,研制了一种矿用泥浆脉冲无线随钻测量装置。该装置由防爆计算机、防爆键盘、防爆数据存储器、防爆测量探管、防爆压力变送器等组成,采用间歇模式工作:防爆测量探管中的测量短节检测到泥浆泵停泵信号后,采集钻孔轨迹参数、定向钻具状态参数等静态数据并进行编码;当检测到泥浆泵开泵信号后,防爆测量探管中的驱动短节依次发送静态数据、测量并发送动态数据,同时控制脉冲发生器调整水力通道的流道面积;防爆压力变送器采集泥浆泵压力信号并将其发送至防爆计算机;数据传输完成后,防爆测量探管停止工作,脉冲发生器内部流道恢复,泥浆泵压力变为正常值,开始定向钻进。试验结果表明,该装置工作稳定,测量数据准确,传输可靠,提高了定向钻进效率和安全性,满足煤矿井下各类煤层孔和岩层孔定向钻进需要,且可实现常规钻孔轨迹随钻测量。     

近钻头连续波反射分析和信号提取算法

连续波载波技术是实现井下随钻测量信息高速上传的有效途径,但由于连续波信号的本质特性使得这一信号在传输通道中的反射、叠加和回响更加剧烈,造成了信号的畸变,从而令井下随钻测量信息的有效提取变得困难。如何实现连续波反射信号的抑制与载波信号的有效提取,是核心内容。为实现这一目的,建立了井下信号传输通道模型,给出了反射过程的理论分析,推导了信号解析算法,明确了工程应用中信号的提取过程,并进行了仿真实验;完成理论分析后,在实地构建的风洞系统中应用所提算法进行了实验,结果进一步验证了算法的有效性,并说明了其在实际工程中推广的可行性。     

新型煤矿井下定向钻进用有线随钻测量装置

针对现有煤矿井下定向钻进用有线随钻测量装置采用孔内电池筒供电存在的使用时间短、信号稳定性差、故障率和维护成本高等不足,提出一种采用孔口防爆计算机为孔内测量探管供电的技术方案;通过对孔口防爆计算机恒压源和信号转换解调设计,测量探管参数测量、二次电源工作和信号载波传输设计,测量软件的开发等关键技术进行研究,研制了防爆计算机供电式有线随钻测量装置,并在专业机构进行了测量精度试验,在神华宁煤集团石嘴山二矿进行了工作稳定性试验,在山西晋煤集团寺河矿进行了测量深度试验。试验结果表明,该装置技术方案可行,测量精度高于设计值,工作稳定性强,传输距离达1 881 m,可满足不同矿井、不同类型定向钻孔钻进需要。     

随钻地层压力测量装置测量控制系统的设计

为了解决地层压力随钻测量中存在的困难,针对地层压力测量装置的工作特点和测试环境,设计了一种基于随钻地层压力测试装置的测量控制系统.系统采用井下涡轮发电机与高温锂电池双电源供电,实现了井下环空压力、管柱压力数据的采集以及井下电磁阀的精确控制和地层压力的预测.随钻过程中可接收到井口下传指令,同时测量数据可实时上传地面.试验测试结果表明,该系统用于测试地层压力是可行的,系统具有设计合理、体积小、功耗低、可靠性高的优点.     

矿用泥浆脉冲无线随钻测量信号发生装置设计

针对煤矿井下定向钻进小泵量、低压力工况,研制了一种矿用泥浆脉冲无线随钻测量装置,分析了该装置的技术要求、结构组成、使用条件;重点阐述了该装置信号发生装置(矿用泥浆脉冲无线随钻测量信号发生装置)的设计方案,介绍了信号发生装置中防爆驱动短节及其电磁阀、脉冲发生器的结构设计,以及脉冲发生器中流道控制阀及其阀头参数设计。现场试验结果表明,信号发生装置能够稳定、可靠地产生泥浆压力脉冲信号,最大信号传输深度达2 570m,泥浆压力脉冲衰减速率为5.8%/hm,衰减速率低,具备向更深钻孔应用的能力。     

基于变换无迹卡尔曼滤波的随钻测量误差在线辨识

针对随钻测量(MWD)工作环境复杂多变,随钻器件测量的精度降低的问题,设计了基于变换无迹卡尔曼滤波(TUKF)法对测量误差进行在线辨识和补偿.首先,建立加速度计和陀螺仪的输出误差模型,选取导航误差参数以及传感器误差参数作为系统状态变量;然后,以钻杆钻进时实时解算出的姿态角与钻机每次停机时的钻具姿态角作差作为系统观测量,设计状态方程和量测方程对惯性器件误差进行在线辨识;最后,通过误差补偿方程对惯性器件进行补偿.运用此方法分别设计了振动台实验、模拟钻进实验和钻进实验,实验结果表明,设计的在线辨识方案通过标定补偿后,随钻测量中钻具的工具面角输出误差减小到0.8°,倾斜角输出误差减小到1°,比无迹卡尔曼滤波方法精度提高了50％,所提方法克服了随钻测量时钻具振动带来的影响,为实际钻井进一步提高数据可信度提供理论依据.     

基于变换无迹卡尔曼滤波的随钻测量误差在线辨识

针对随钻测量(MWD)工作环境复杂多变,随钻器件测量的精度降低的问题,设计了基于变换无迹卡尔曼滤波(TUKF)法对测量误差进行在线辨识和补偿.首先,建立加速度计和陀螺仪的输出误差模型,选取导航误差参数以及传感器误差参数作为系统状态变量;然后,以钻杆钻进时实时解算出的姿态角与钻机每次停机时的钻具姿态角作差作为系统观测量,设计状态方程和量测方程对惯性器件误差进行在线辨识;最后,通过误差补偿方程对惯性器件进行补偿.运用此方法分别设计了振动台实验、模拟钻进实验和钻进实验,实验结果表明,设计的在线辨识方案通过标定补偿后,随钻测量中钻具的工具面角输出误差减小到0.8°,倾斜角输出误差减小到1°,比无迹卡尔曼滤波方法精度提高了50％,所提方法克服了随钻测量时钻具振动带来的影响,为实际钻井进一步提高数据可信度提供理论依据.     

应变式井下工程参数测量传感器组桥与布片研究

为了实时了解井下钻头的工作情况,提高钻井的安全性和可靠性,设计了一种应变式传感器。该传感器使用4组全桥方式的测量电桥。测量电桥采用科学的布片和组桥方法,能同时测量钻压、扭矩和钻头所受的侧向力,并有效抵消温度对测量参数的影响,从而降低各测量参数之间的耦合影响。针对井下恶劣的工况条件,采用了镍铬铝合金制作的金属箔式应变片。该应变片能够抗高温、抗蠕变和耐腐蚀。现场试验结果表明,各组测量电桥能够满足实际工况需要。     

未来智能钻井系统

展望了未来智能钻井技术的系统组成、功能及其运行方式.智能钻井新技术是钻井技术、新材料技术、检测控制、微电子技术、通信和计算机、机器人和超微加工技术等的集成.未来的智能钻井将采用轻便车载连续油管全自动钻机,钻井作业中,安置在钻头上的智能机器人将观测和检测到的所有井下参数上传到地面,在钻井的同时完成测井工作;地面人员通过控制钻头运动轨迹和转速,实现遥控智能钻井;起下钻等钻井作业均由地面机器人按指令自动完成;通过通信网络技术,实现全球钻井协同工作.因此,智能钻井将大幅度降低钻井成本,大大提高钻井速度,减少钻井事故的产生,实现井眼轨迹的精确控制,进一步提高石油天然气勘探开发技术水平.     

Simulation and optimization of machining parameters in drilling of titanium alloys

The present study attempts to analyse the effect of various drilling parameters such as spindle speed, feed rate and drill bit diameter on performance characteristics such as thrust force, torque and circularity at entry and exit of the holes in drilling of titanium alloy using coated drill bit. A three dimensional machining model based on Lagrangian approach is developed using DEFORM-3D software. The performance characteristics obtained through simulation model is compared with experimental results. The simulation model closely agree with the experimental results as percentage relative error of 4.93, 9.01, 6.04 and 3.0 is observed for thrust, torque circularity at entry and circularity at exit respectively. The experimental data is used to develop valid empirical models to relate performance characteristics with drilling parameters using non-linear regression analysis. The empirical model helps to predict various performance characteristics without resorting to rigorous analysis through the numerical model. The values of various performance characteristics predicted from empirical models are compared with experimental results and the percentage relative error within 10% is observed. Finally, an improved version of latest evolutionary approach known as Harmony Search (HS) algorithm has been proposed to obtain favorable machining conditions through optimization of each performance characteristic. The optimal value of circularity at entry is obtained as 0.985 (approaching towards ideal value of one) when spindle speed, feed rate and drill bit diameter are set at 530.86 (≈531) RPM, 44.8 (≈45) mm/min and 7 mm, respectively. Similarly, optimal value of circularity at exit reaches 0.979 with same spindle speed and drill bit diameter but feed rate of 50 mm/min.     

深水表层钻井随钻压力与温度监测装置设计

深水表层钻井随钻压力与温度监测装置是监测深水表层钻井过程中井底当量循环密度（ECD）和循环温度的重要工具。通过深水表层钻井随钻压力与温度监测装置,现场技术人员可以实时掌握井下环空压力、钻柱内压和温度等工程参数,进而了解和分析井下工况,为深水表层钻井作业和动态压井钻井技术提供指导。设计的深水表层钻井随钻压力与温度监测装置以ARM为核心,利用数据采集技术和通信技术,实现了随钻压力与温度的采集传输。完成的深水表层钻井随钻压力与温度监测装置具有体积小、功耗低、抗振动和抗高温和低温的优点。监测装置已经在我国南海第一口深水井LW6—1—1井的领眼井中成功进行应用试验,验证了其在深水无隔水管钻井条件下的机械强度、稳定性、可靠性,测量得的数据能真实反映钻井工况。     

基于双处理器架构的地层压力测控系统设计

针对地层压力随钻测量困难、耗时等问题,以及工具下入困难、工具遇卡等潜在风险,提出了一种基于双处理器的随钻地层压力测量控制系统。在随钻过程中通过压力传感器测量井下压力,由主处理器TMS320F2812对地层压力值进行采集与处理;从处理器ATMEGA8对电磁阀进行智能控制,实现分流器、换向器与执行机构的协调配合,从而获得实时地层压力数据。实验结果表明：该系统实现了在井下高温、高压和强干扰的恶劣环境下对压力信号进行采集、分析、传输和存储,系统设计合理并具有较好的抗干扰性与实用性。     

Development of a monocular vision system for robotic drilling

Robotic drilling for aerospace structures demands a high positioning accuracy of the robot, which is usually achieved through error measurement and compensation. In this paper, we report the development of a practical monocular vision system for measurement of the relative error between the drill tool center point （TCP） and the reference hole. First, the principle of relative error measurement with the vision system is explained, followed by a detailed discussion on the hardware components, software components, and system integration. The elliptical contour extraction algorithm is presented for accurate and robust reference hole detection. System calibration is of key importance to the measurement accuracy of a vision system. A new method is proposed for the simultaneous calibration of camera internal parameters and hand-eye relationship with a dedicated calibration board. Extensive measurement experiments have been performed on a robotic drilling system. Experimental results show that the measurement accuracy of the developed vision system is higher than 0.15 mm, which meets the requirement of robotic drilling for aircraft structures.     

A new test bench system for hammer drills: Validation for handle vibration

Workers' can be exposed to high levels of hand vibration when drilling into concrete or rock using hammer drills; exposures that can cause hand arm vibration syndrome. Exposure levels may be reduced by different drill and bit designs and drilling methods, but these interventions have not been systematically evaluated. The purpose of this project was to develop a robotic test bench system for measuring handle vibration on drills in order to compare differences in drill designs, power sources, bit designs and drilling methods. The test bench is a departure from the ISO method for measuring drill handle vibration (ISO 28927-10), which requires drilling by humans. The test bench system was designed to repeatedly drill into concrete blocks under force control while productivity and handle vibration were measured. Handle vibration levels with different drills and bit sizes were similar to those collected following ISO methods. A new robotic test bench system for measuring handle vibration is presented and validated against ISO methods and demonstrates dynamic properties similar to human drilling.     

一种用于井下电源质量监测的EMI采集与处理电路

随钻测井仪器工作于高温、高压等恶劣环境下,对电源质量进行监测可避免电子系统因供电问题而死机。由于钻铤内部空间狭窄且传输带宽有限,使得测量电流电压的传统方法并不适用。根据电磁干扰(EMI)信号的设备独立性和导体传播等特点,设计了一种电源线上的EMI信号在线采集与处理电路,适用于井下电源质量监测。该电路设计了低通、放大、抗混叠滤波等完整信号调理链路,并研制了高速模数转换模块,使用FPGA+STM32的运算架构将EMI信号实时转换为频谱。在FPGA中实现了模数转换器(ADC)的时序控制和可变静态存储控制器(FSMC)总线驱动,使得系统能够自主配置ADC的采样率和采样数目,采样率可达40 MHz。实验结果表明本电路具有良好的信号调理性能,通频带纹波低于0.1 dB,能够可靠地完成随钻测井仪器电源线上EMI信号的频谱采集。     

Nonlinear output‐feedback control of torsional vibrations in drilling systems

This paper considers the design of a nonlinear observer‐based output‐feedback controller for oil‐field drill‐string systems aiming to eliminate (torsional) stick–slip oscillations. Such vibrations decrease the performance and reliability of drilling systems and can ultimately lead to system failure. Current industrial controllers regularly fail to eliminate stick–slip vibrations under increasingly challenging operating conditions caused by the tendency towards drilling deeper and inclined wells, where multiple vibrational modes play a role in the occurrence of stick–slip vibrations. As a basis for controller synthesis, a multi‐modal model of the torsional drill‐string dynamics for a real rig is employed, and a bit–rock interaction model with severe velocity‐weakening effect is used. The proposed model‐based controller design methodology consists of a state‐feedback controller and a (nonlinear) observer. Conditions, guaranteeing asymptotic stability of the desired equilibrium, corresponding to nominal drilling operation, are presented. The proposed control strategy has a significant advantage over existing vibration control systems as it can effectively cope with multiple modes of torsional vibration. Case study results using the proposed control strategy show that stick–slip oscillations can indeed be eliminated in realistic drilling scenarios in which industrial controllers fail to do so. Moreover, key robustness aspects of the control system involving the robustness against uncertainties in the bit–rock interaction and changing operational conditions are evidenced. Copyright © 2017 John Wiley & Sons, Ltd.     

复杂变时滞作用下的钻头纵扭耦合非线性振动

油气探采中的钻柱是一个纵扭耦合的超大柔性转子系统,该系统在钻头-岩层切削界面的时滞、非光滑效应作用下极易产生破坏性的黏滑振动失稳并造成钻柱失效.研究围绕钻柱纵-扭耦合动力学及时滞稳定性问题展开,考虑钻柱内部结构阻尼、外部阻尼、重力、钻井液浮力以及更一般的顶部边界,建立了钻柱4自由度缩减模型.同时,基于井底钻头存在跳钻与扭振的实际工况,在钻头-岩层界面引入了多重再生切削效应,建立了复杂变时滞作用下的钻柱纵扭耦合非线性动力学模型.随后,基于半离散法,得到了该系统的线性派生时滞系统的稳定性判据,并在转速-钻压参数平面得到了稳定钻进的参数包络线.通过参数研究,分析了顶部边界条件、岩层强度等因素对钻柱参数空间稳定性包络线的影响.同时,通过对系统的时域非线性仿真,验证了稳定性分析的正确性并重现了井底钻头的黏滑运动、跳钻、钻头反转等多种强非线性运动.最后,对时滞引起的钻柱自激振动,通过优化的顶部柔顺边界实现了振动抑制,为钻柱纵扭耦合振动的抑制提供一种简单有效的思路.     

基于改进LS-SVM的随钻测量数据传输误码率预测

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