Use of neural networks for the prediction of frictional drag and transmission of axial load in horizontal wellbores     

Tanvir Sadiq  Ridha B. Gharbi  Hans C. Juvkam‐Wold 《国际地质力学数值与分析法杂志》2003,27(2):111-131

The use of mud motors and other tools to accomplish forward motion of the bit in extended reach and horizontal wells allows avoiding large amounts of torque caused by rotation of the whole drill string. The forward motion of the drill string, however, is resisted by excessive amount of friction. In the presence of large compressive axial loads, the drill pipe or coiled tubing tends to buckle into a helix in horizontal boreholes. This causes additional frictional drag resisting the transmission of axial load (resulting from surface slack‐off force) to the bit. As the magnitude of the frictional drag increases, a buckled pipe may become ‘locked‐up’ making it almost impossible to drill further. In case of packers, the frictional drag may inhibit the transmission of set‐up load to the packer. A prior knowledge of the magnitude of frictional drag for a given axial load and radial clearance can help avoid lock‐up conditions and costly failure of the tubular. In this study a neural network model, for the prediction of frictional drag and axial load transmission in horizontal wellbores, is presented. Several neural network architectures were designed and tested to obtain the most accurate prediction. After cross‐validation of the Back Propagation Neural Network (BPNN) algorithm, a two‐hidden layer model was chosen for simultaneous prediction of frictional drag and axial load transmission. A comparison of results obtained from BPNN and General Regression Neural Network (GRNN) algorithms is also presented. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   

大力开展直接找油找气技术研究     

陆邦干 《地球物理学进展》2002,17(2):277-280

提出了直接找渍气的必要性和可能性,回顾了以往失误的原因,推荐了百灵软件,并期望各石油公司经理层能使用该软件,化较小的代价对地震资料进一步解释利用而提高钻井成功率,并最终降低油气成本。  相似文献   

浅议地质录井技术在煤田地质勘探中的运用     

王高科 《中国煤田地质》2007,19(5):72-73,81

地质录井作为石油地质的一项必需技术已为地质界所公认,在石油钻探中,录井技术可以较准确地判定油砂层的位置,将地质录井技术运用到煤田、水文钻探中,可以在取心失败或者无心钻进中有效判定目的层层位。地质录井资料,也是测井解释的重要依据。  相似文献   

绳索取心钻进技术在复杂地层的应用     

彭步涛 《中国煤田地质》2007,19(A01):9-11

福建煤田地质121队在福建、云南、贵州、四川等省份的复杂煤田勘探区推广应用绳索取心金刚石钻进技术，取得了较好的应用效果。通过分析云、贵、州、闽地区的地层特点，介绍了该类地区钻孔结构、冲洗液技术及护壁堵漏技术。在钻具配套、硬岩钻进等方面也进行了有效的探索，并以实例和大量数据说明121队在绳钻技术方面的应用水平。  相似文献   

煤炭TK-3型液压钻机回转器技术改造研究     

黄俊才 《中国煤田地质》2007,19(A01):12-13,28

根据TK-3型液压立轴式岩心钻机结构分析产生液压卡盘失灵、主动钻杆卡死等故障的原因．提出了两套改造方案。通过车间空载试车及野外现场钻进验证，改进方案可行，完全符合煤炭地质钻探金刚石钻进、绳索取心技术工艺要求。  相似文献   

米104盐井对接施工工艺实例     

王增海王永全  崔秀忠吴国强 《中国煤田地质》2007,19(A01):24-26

米104井位于陕西省榆林市米脂县，与米103井相距350m，设计对接靶点垂深2536．05m，造斜点垂深2330m．水平段124．79m。该井设计为三开井身结构，在施工中，根据不同的岩性采用了不同的的施工工艺及不同的钻井液。米104井钻进深度至2789m时，泥浆全部漏失，达到了一次对接成功。  相似文献   

长螺旋混凝土压灌桩在地基处理中的应用     

陈志亮 《中国煤田地质》2007,19(A01):70-71,77

茂名石化100万t/a乙烯改扩建工程场地位于破碎带上，场区地质条件复杂。在厂区地基处理中，采用长螺旋混凝土压灌施工方法。施工过程中严格对正桩孔，控制转速，按比例合理配制混凝土，并针对该类型桩施工中常见的7种质量缺陷提出了相应解决方案和控制措施。  相似文献   

套管开窗侧钻技术在水井施工中的应用     

王永全王玉春  梁凤河张书平 崔秀忠 《中国煤田地质》2007,19(A01):78-80,91

套管开窗侧钻技术是处理井内复杂情况的一种有效手段，某地热井在完井抽水后，因取水段岩层垮塌造成取水井段堵塞，采用冲、扫、捞、等方法处理均无效，地热井几近报废，后采用该技术手段，使该井顺利竣工。  相似文献   

Oceanic basalt continuous thermal demagnetization curves     

Jürgen Matzka  David Krása 《Geophysical Journal International》2007,169(3):941-950

The palaeomagnetic standard technique of stepwise thermal demagnetization (STD), long regarded as unreliable for oceanic basalts that have undergone low temperature alteration, has recently been applied in a number of studies to characterize the natural remanent magnetization (NRM) of such rocks. In order to better understand STD data of oceanic basalts, and to possibly identify the magnetominerals that are carrying the NRM, we have carried out a number of continuous and STD experiments on seven oceanic basalt samples. During continuous thermal demagnetization (CTD), a sample is heated to a certain temperature and its NRM is measured during heating and subsequent cooling. Even when CTD reveals only titanomaghemite unblocking at 400°C as the remanence carrier, STD behaviour can be very complex and unblocking is observed at temperatures of up to 500°C and higher. CTD also allowed to identify a partial or full self-reversal of NRM due to interaction between two types of magnetominerals in one sample. The higher degree of maghemitization of smaller titanomaghemite grains with respect to larger ones, which are less efficient in carrying the remanence, was seen for three samples by a shift of 80°C between the strong field thermomagnetic curve and the NRM measured at elevated temperature. In several cases, the identification of the NRM-carrying magnetomineral was not possible from CTD data due to the ambiguity of Curie temperatures in the titanomagnetite/titanomaghemite system.  相似文献   

中国大陆科学钻探工程卫星孔CCSDPP6钻孔橄榄岩岩石学研究   总被引：1，自引：0，他引：1       下载免费PDF全文

任玉峰杨经绥  张仲明李天福 《地质学报》2007,81(7):1004-1016

中国大陆科学钻探工程卫星孔PP6钻孔位于苏鲁超高压变质带的山东荣成滕家集马草夼橄榄岩体中。该橄榄岩出露于元古代花岗闪长片麻岩中,面积为300m×130m。地表岩石风化强烈,钻孔内岩石新鲜,劈理发育。孔深196m,橄榄岩厚度约110m,下部为花岗闪长片麻岩。橄榄岩主体呈块状构造,边缘呈条带状构造,靠近片麻岩的橄榄岩蛇纹石化强烈。除了10cm厚的岩脉原岩为岩浆分异的产物外,岩石主元素、微量和稀土元素地球化学显示,原岩为极亏损的地幔方辉橄榄岩。岩石主要矿物组成为橄榄石(85%~95%) 斜方辉石(3%~5%) 角闪石(3%~5%) 尖晶石(约0.5%) 镍硫化物(<0.1%),个别部位含有石榴石、单斜辉石和白云石。根据矿物的结构和成分,大体分为三个期次的组合。早期残余地幔矿物组合,由镁橄榄石、富铝顽火辉石、铬尖晶石和透辉石组成,具残余斑状结构,常含有包体,为高温低压组合;超高压变质期矿物组合,由镁橄榄石、镁铝榴石(Pyr=62~66)、低铝顽火辉石、铬尖晶石组成,具细粒变晶结构,无包体,变质温压为840~940°C、3.0~4.1GPa;麻粒岩相─角闪岩相变质期矿物组合,包括韭闪石、镁铝尖晶石、铬尖晶石、白云石、透闪石、蛇纹石,变质温度和压力为650~780℃、<1.8GPa。马草夼橄榄岩作为地幔楔,在印支期发生了超高压变质作用,并在折返过程中叠加了麻粒岩相-角闪岩相的变质作用。  相似文献