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1.
井眼形成是通过钻头牙齿破碎岩石形成岩屑来实现的,对钻头牙齿侵入破岩机理的认识有助于优化钻头结构,提高工
具破岩效率。阐述了钻头牙齿与岩石相互作用机理的复杂性,分别从弹性力学、裂纹扩展、数值模拟等几个方面,综述了钻头牙齿
与岩石相互作用机理的研究进展,指出了今后的研究重点。虽然前人开展了众多的物理实验与数值模拟研究,但是由于钻头牙齿
破岩过程及井底环境的复杂性,目前为止其机理并没有被完全认识清楚。理论与实验研究证明,井底压力是影响机械钻速的重要
因素之一,针对钻头牙齿与岩石相互作用机理的复杂性,建议采用先进实验和数值模拟技术,将物理实验和数值模拟结合开展研
究,揭示井底复杂应力环境下钻头牙齿的破岩机理将成为未来的研究重点。   相似文献   

2.
单齿破壤机理的研究是太空取样钻头研发非常重要和迫切的任务,是实现中国三期探月工程的月表钻进取样要求的重
要研发基础。分析了反映月壤物理力学特性的主要参数及其之间的相关性及变化趋势,初步确定了2.5m深度内月壤物理力学
的参数范围;基于月壤物理力学特性和月表钻进的钻进工艺分析,得出表层钻进和浅层钻进时月壤的破坏形式不同于土的掘削失
效模型,主要是回转剪切破坏;提出了土的回转剪切力学模型,推导回转切削土阻力矩公式;得出阻力矩主要与钻头直径和切削刃
宽度、月壤的容重和钻进深度等相关,并对其相关性进行了分析说明。   相似文献   

3.
鞍子山超单元由四个单元组成,各单元叶理构造极为发育,闪长质包体剪切压扁强烈,钾长石斑晶总体按优选方位定向,三者产状一致,平行接触带分布。从早期单元到晚期单元随着叶理构造发育强度减弱,闪长质包体数量减少,剪切压扁程度降低;钾长石斑晶从按优选方位定向到杂乱分布。将其划分为强侵位变形、中等侵位变形、弱侵位变形及基本无侵位变形四个侵位变形带。通过对各单元闪长质包体测量,计算弗林指数K值为0<K<1,属压扁型应变椭球体,即形成L<S岩组类型。根据超单元分布的构造位置及形态。各单元群居关系特征,结合野外包体旋转指向及镜下定向薄片资料分析,认为该超单元岩浆就位受区内北东向吴炉—郑家山—上腰岭左旋剪切带控制,属剪切楔形侵入膨胀式岩浆就位机制。  相似文献   

4.
针对普光气藏储层普遍具有储层厚度大、层间非均质性强、生产井段长、产量高、生产压差小特点,导致二项式产能分析的直线段斜率对井底流压非常敏感,巨厚气藏的井底流压的取值深度不再能简单地选取地层的中部深度,产能试井解释出现异常(负斜率),综合考虑储层的巨厚、非均质性对井筒压力分布影响,利用数值模拟,分析井底压力计位置对产能方程影响,给出长井段合采产能方程出现异常(负斜率)原因,建立考虑地层系数影响的消除长井段合采产能方程异常的方法,即将压力计放在地层系数为总地层系数1/2的位置.该方法能有效避免二项式产能分析过程中出现负斜率的现象.  相似文献   

5.
开鲁盆地陆东凹陷原油包括轻质油、中质油和重质油,原油物性特征复杂.采集陆东凹陷30个烃源岩岩心样品、12个油砂样品和10个原油样品,进行饱和烃色谱质谱测试,分析原油和烃源岩母质类型、成熟度等地球化学特征,研究原油物性分布规律及油藏保存条件.结果表明:陆东凹陷烃源岩不具备生成规模原生稠油的条件,稠油为次生成因,具有生物降解和氧化的特征;纵向上,原油物性随埋藏深度增大而逐渐变好;平面上,原油物性自断阶带向洼陷带逐渐变好.在稠油油藏区,白垩世末至第四纪发育的断裂和火山运动、地表水下侵,导致断阶带地层水矿化度异常偏低,油藏保存条件变差,加剧原油生物降解、氧化等次生变化.该结果为研究区下一步勘探开发指明方向.  相似文献   

6.
胶南-威海造山带基底主要由新元古代变质花岗岩组成,另有少量变质表壳岩、浅变质碎屑岩、基性-超基性岩及榴辉岩.变质花岗岩可分为同造山花岗岩及后造山花岗岩.造山带之上曾经有过古生代盖层,造山带中侵入有三叠纪闪长岩及花岗岩体.在榴辉岩及其围岩中发现了许多高压、超高压变质矿物;确认高压、超高压变质作用分早期的超高压榴辉岩相变质作用和晚期的高压绿片岩相变质作用;变质地层、超镁铁质岩及部分片麻岩等围岩与榴辉岩经历了相同的超高压变质作用,大部分花岗质片麻岩是在超高压变质作用发生后或发生过程中侵入榴辉岩中的.苏鲁造山带是一条以韧性剪切带为格架,穹窿构造、褶皱构造相伴随的“无山“的造山带;造山带可分为南、北二部分,北带主体属于华北板块南缘带,而南带主体则属于扬子板块北缘带.南、北带的界线大致与连云港-嘉山断裂及近岸断裂一致.造山带南界与响水-淮阴断裂一致,北界位于五莲-王台-朱吴-牟平一线,西侧被郯庐断裂带切割.  相似文献   

7.
胶南-威海造山带研究进展及重要地质问题讨论   总被引:1,自引:0,他引:1  
胶南-威海造山带基底主要由新元古代变质花岗岩组成,另有少量变质表壳岩、浅变质碎屑岩、基性-超基性岩及榴辉岩.变质花岗岩可分为同造山花岗岩及后造山花岗岩.造山带之上曾经有过古生代盖层,造山带中侵入有三叠纪闪长岩及花岗岩体.在榴辉岩及其围岩中发现了许多高压、超高压变质矿物;确认高压、超高压变质作用分早期的超高压榴辉岩相变质作用和晚期的高压绿片岩相变质作用;变质地层、超镁铁质岩及部分片麻岩等围岩与榴辉岩经历了相同的超高压变质作用,大部分花岗质片麻岩是在超高压变质作用发生后或发生过程中侵入榴辉岩中的.苏鲁造山带是一条以韧性剪切带为格架,穹窿构造、褶皱构造相伴随的"无山"的造山带;造山带可分为南、北二部分,北带主体属于华北板块南缘带,而南带主体则属于扬子板块北缘带.南、北带的界线大致与连云港-嘉山断裂及近岸断裂一致.造山带南界与响水-淮阴断裂一致,北界位于五莲-王台-朱吴-牟平一线,西侧被郯庐断裂带切割.  相似文献   

8.
Air down-the-hole(DTH)hammer drilling has long been recognized to have the potential of drilling faster than conventional rotary drill,especially in some hard rocks such as granite,sandstone,limestone,dolomite,etc.with the same weight on bit(WOB)and rotations per minute(RPM).So,it has been widely used in many drilling fields including mineral resource exploration drilling,oil and gas drilling and geothermal drilling.In order to reduce drilling cost by selecting optimal drilling parameters,rate of penetration(ROP)should be estimated accurately and the effects of different factors on ROP should be analyzed.In this research,ANN model with several multi-layer perception back propagation(BP)networks for predicting ROP of air DTH hammer drilling was developed using controllable parameters such as impact energy,impact frequency,WOB,RPM and bit operating time for the formations with a certain drillability index of rock.Several BP neural networks with the different neurons in hidden layers were developed and compared for selecting optimal architecture of ANN.The effects of the drilling parameters such as impact energy,impacting frequency,WOB,RPM and bit operating time on the ROP of air DTH hammer drilling were investigated by trained ANN.From the analyses,the optimum range of drilling parameters for providing high ROP were determined and analyzed for a formation with a certain drillability index of rock.The methodology proposed in this study can be used in many mathematical problems for optimization of drilling process with air DTH hammer.  相似文献   

9.
The authors tested the percussion-extruding Down-the-hole (DTH)hammer bit with five different structures and mainly analyzed the drilling mechanism between conical bit and stepped bit. In addition, aiming at "the pile effect" in combination with the advantage' of stepped bit, we design a new cam spinning bit and test it outdoors. The result shows that using cam spinning bit can solve the problem of "the pile effect", which can also obtain higher drilling efficiency than using conical bit in high confining pressure strata. It is characterized by novel structure and high drilling speed as well as good guiding, and it is significant for improving efficiency in percussion-extruding drilling technique.  相似文献   

10.
顶进力是顶管工程设计和施工中最重要的参数之一, 顶进力计算的精确性将直接影响顶管的工程的成败。随着顶管施工工艺越来越多的应用于岩石地层, 但鲜有关于岩石地层中顶管顶进力的计算模型。为了更加准确地计算岩石地层中的迎面阻力, 假设掌子面稳定, 通过分析岩石顶管机刀盘滚刀破岩机理、受力模型和影响规律, 在此基础上推导出岩石地层顶管迎面阻力计算公式。结果表明: 岩石顶管中, 岩石抗压强度和抗剪强度以及顶管机滚刀切入深度直接决定了迎面阻力的大小, 实测迎面阻力除个别点在计算值上下限以外, 其余与公式预测值相一致, 证明其具有适用性。   相似文献   

11.
The authors tested the percussion-extruding Down-the-hole(DTH)hammer bit with five different structures and mainly analyzed the drilling mechanism between conical bit and stepped bit. In addition, aiming at "the pile effect" in combination with the advantage of stepped bit, we design a new cam spinning bit and test it outdoors. The result shows that using cam spinning bit can solve the problem of "the pile effect", which can also obtain higher drilling efficiency than using conical bit in high confining pressure strata. It is characterized by novel structure and high drilling speed as well as good guiding, and it is significant for improving efficiency in percussion-extruding drilling technique.  相似文献   

12.
青岛市黄岛区拟建设海底地下油气储藏库,前期地质勘察工作要求施工倾角45°、深220m的取心钻孔4个,并在孔内分段进行压水试验.本文介绍了如何利用XY-4型金刚石小口径钻机施工基岩深斜孔及压水试验技术.  相似文献   

13.
A survey was conducted in the equatorial area of Indian Ocean for a better understanding of the dynamics of hook depth distribution of pelagic longline fishery.We determined the relationship between hook depth and vertical shear of current coefficiency,wind speed,hook position code,sine of wind angle,sine of angle of attack and weight of messenger weight.We identified the hook depth models by the analysis of covariance with a general linear model.The results showed that the wind effect on the hook depth can be ignored from October to November in the survey area;the surface current effect on the hook depth can be ignored;the equatorial undercurrent is the key factor for the hook depth in Indian Ocean;and there is a negative correlation between the hook depth and vertical shear of current and angle of attack.It was also found that the deeper the hook was set,the higher hook depth shoaling was.The proposed model improves the accuracy of the prediction of hook depth,which can be used to estimate the vertical distribution of pelagic fish in water column.  相似文献   

14.
Drilling operations in polar regions and mountainous areas are complicated by nature of the extreme environment. Yet conventional rotary drilling technologies can be used to drill ice for scientific samples and other research. Due to such reasons as power consumption and weight complications,it is hard to apply a conventional rotary drilling rig for glacial exploration. Use of small,relatively lightweight,portable engine-powered drilling systems in which the drill lifting from the borehole is carried by the winch. It is reasonable enough for near-surface shallow ice-drilling down to 50 m. Such systems can be used for near-surface ablation-stakes installation,also temperature measurements at the bottom of active strata layer,revealing of anthropogenic pollution,etc. The specified used in this research is an auger ice drill powered by a gasoline engine. At this stage,it is crucial to choose effective drilling parameters such as weight on bit( WOB) and drill bit rotation rate. Sensors equipped on the rig have measured the main parameters of the drilling process,such as drill speed,WOB,drill rotation speed,torque and temperature. This paper addresses research on drilling parameters of engine powered auger ice drill and supplies some recommendations for optimization of any ice-core drilling process.  相似文献   

15.
碳酸盐岩声波传播特征具有重要的应用价值,系统性地分析流体类型、流体压力、温度及围压对碳酸盐岩声波速度与频谱特性影响的研究仍需加强。选取四川盆地合川-潼南地区灯影组缝洞碳酸盐岩,开展了不同条件下的声波透射实验,分析了围压、孔隙压力、压力差、温度及流体类型对碳酸盐岩样品声波速度的影响及不同条件下透射声波的主频特征。研究结果表明:饱和地层水时声波速度对压力变化的敏感度较饱和氮气时低。压力变化过程中,声波速度变化幅度与岩样孔隙度为正相关关系。实验温度范围内,随着温度逐渐升高,饱和地层水、氮气岩心纵波速度、横波速度均小幅降低。当差应力较低时,通过改变孔隙压力来改变差应力的方式对应的声波速度大于通过改变围压来改变差应力方式对应的声波速度,当差应力较高时,结论相反。相同差应力条件下,声波速度对围压变化较孔隙压力变化更为敏感。定围压变孔隙压力与定孔压变围压曲线所对应的2条声波速度-差应力关系曲线的夹角及斜率差可定性反映岩样动态Biot有效应力系数相对大小。随着差应力增大,孔隙压力对有效应力的贡献逐渐降低。随着孔隙压力增大,纵波主频幅值、横波主频幅值均逐渐下降,随着围压增大,纵波主频幅值、横波主频幅值均逐渐增大,随着温度逐渐升高,纵波主频幅值、横波主频幅值均逐渐增大。研究结果有助于基于测井声波信息开展碳酸盐岩地层孔隙压力预测相关理论研究及工程应用。   相似文献   

16.
地震会对核电站安全造成影响。随着核电站的数量越来越多, 有必要关注在地震下核电站的安全。核反应堆厂房是核电站重要的组成部分, 研究其地震响应对核电站有着重要意义。基于直接法, 考虑了3种不同场地(中硬土、软岩、硬岩)在地震下的塑性变形和土的滞回阻尼, 使用FLAC3D对土-核反应堆厂房模型系统进行了三维建模。为了捕捉上部结构与下部岩石/土壤之间的分离与滑动, 在核反应堆厂房基础与岩石/土壤表面设置接触面单元。上层结构以集总质量模型模拟, 同时考虑土-结构相互作用下基岩深度对核反应堆厂房基础地震响应的影响, 最终得到核反应堆厂房结构杆件的加速度反应谱、剪力、基础的摇动和基础不均匀沉降以及侧向位移。结果表明: 在中硬土场地中, 位移、剪切力随基岩深度的增大而减小; 在硬岩场地中, 位移和剪切力响应的规律呈相反趋势; 在软岩场地中, 上部结构响应的规律较为复杂。对于基础摇动和基础不均匀沉降, 在中硬土场地中, 其呈现的规律随基岩深度增大而减小; 在软岩和硬岩场地中, 并无明显规律。基础不均匀沉降可直接反映结构的破坏情况。中硬土场地下基础不均匀沉降超过容许值, 所以基础不均匀沉降对核反应堆厂房的影响不容忽视, 这对核电站的安全设计十分重要。   相似文献   

17.
In recent years, air-foam combining the advantages of both liquid and air drilling has been utilized as a drilling medium. Air-foam drilling has proved its efficiency in numerous situations where serious problems were encountered, such as in fractured formations and depleted or high permeable zones. However, the major disadvantage of air-foam drilling system is that the foam can only be used once, so that an extremely large pit is required to contain the foam to allow sufficient room for cuttings and for the foam to dissipate. Moreover, it needs enormous volume prepared, consuming abundance of water and ingredient additives, which results in the high cost of foam drilling. The recycling foam fluid by using foam breaking technology is the only effective method to solve these problems associated with the known foam drilling. Various types of equipment and technique have been employed to suppress foam formation in biological and process equipment in foam drilling. The study described various methods of foam breaking technology, and the trend of the foam breaking technology for foam drilling is discussed.  相似文献   

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