绳索取心钻进技术在松散盐岩地层中的应用探讨          下载免费PDF全文

李金锁  张少林  刘江  张佳文 《探矿工程》2015,42(7):5-9

地质岩心钻探中,岩心采取率一直是地质找矿、地学科研工作者重点关注的对象,也是岩心钻探重要的考核指标。传统的钻探取心方法在松散、软弱、含盐地层,特别是含易溶盐地层的取心质量不佳;绳索取心钻探在完整地层取心效果较为理想,同时可大大提高劳动生产率、降低劳动强度,而对于松散、软弱地层,其取心难度比起传统钻探有时更为复杂。通过柴达木盆地达布逊干盐湖科学钻探工程,对钻遇的地表层、松散地层如何采取技术方法提高岩心采取率进行了探索和研究。实践证明,通过改善冲洗液性能、改进取心卡簧特性及钻头出水方式3个方面技术措施,可大大提高绳索取心钻进在松散、软弱、弱固结、含盐地层的岩心采取率,由改进前的平均30%提高为平均96%。  相似文献   

绳索取心深孔偏心楔同径侧钻绕障技术实践          下载免费PDF全文

王红阳  罗永贵  腾新明 《探矿工程》2015,42(6):17-20

招远市栾家河金矿区 47ZK3孔设计孔深2570 m,于孔深2297 m处发生跑钻事故,处理至孔内事故底部时,处理难度增大。为加快事故处理进度,降低事故损失,采用偏心楔侧钻技术进行同径造斜的方法,绕开事故段。通过对偏心楔设计、偏心楔制作与安装、造斜钻头及分支钻进钻头选择等技术措施进行优化,较好地解决了偏心楔侧钻过程中偏心楔固定及过斜面工序的关键技术问题,顺利地将分支孔延伸至终孔。  相似文献   

基于LS-DYNA的贯通式潜孔锤反循环钻头强度的优化分析          下载免费PDF全文

李鹏  殷琨  彭枧明  罗永江  李丽佳 《探矿工程》2015,42(3):44-47

通体花键式贯通式潜孔锤反循环钻头在实际施工中尾部较易损坏,影响反循环钻头的使用寿命。为提高反循环钻头的使用寿命,对反循环钻头尾部结构进行了优化设计,并采用非线性动力学仿真软件LS-DYNA对改进前后的反循环钻头进行了仿真分析。分析结果表明：由于在冲锤的高频冲击作用下,反循环钻头尾部易出现较大的局部应力集中,导致钻头体出现疲劳破坏;通过对钻头尾部结构设计优化后,与通体花键式反循环钻头相比,新结构钻头在无泄风槽情况下,应力集中值减小44%,在有泄风槽的情况下,应力集中值减小19%。数值模拟分析表明,优化后能大幅度提高钻头寿命。  相似文献   

高模数水玻璃钾基抑制冲洗液在蠕变坍塌地层中的应用          下载免费PDF全文

张波  郑秀华  汪传武 《探矿工程》2015,42(9):42-45

在青海埃坑南矿区钻遇含角砾石的断层泥地层,孔壁坍塌、掉块,卡钻事故时有发生,几乎无法继续钻进,使用水玻璃与相关钻井液处理剂配合使用制备水玻璃钾基抑制冲洗液,用来平衡地层压力保护孔壁,并且加大金刚石钻头及扩孔器外径,解决了钻孔坍塌、缩径以及卡钻等问题,使施工顺利进行,为后续施工提供了参考方法。  相似文献   

PDC钻头切削齿布齿设计的新思路          下载免费PDF全文

金永男  陈宗涛  由昌英  段隆臣 《探矿工程》2015,42(5):72-76

切削齿布齿设计是PDC钻头设计的关键。为提高PDC钻头的钻进效率,综合考虑PDC钻头切削齿的设计特点和切削先后顺序等因素,并且通过对PDC钻头单切削齿实验结果进行分析,提出了以冠部轮廓法线为基准的切削齿布齿设计方法。  相似文献   

Application of linear and nonlinear techniques in river flow forecasting in the Kilombero River basin,Tanzania / Application de techniques linéaires et non-linéaires à la prévision des débits dans le bassin de la Rivière Kilombero,en Tanzanie     

《水文科学杂志》2013,58(5)

Abstract

Modelling of the rainfall–runoff transformation process and routing of river flows in the Kilombero River basin and its five sub-catchments within the Rufiji River basin in Tanzania was undertaken using three system (black-box) models—a simple linear model, a linear perturbation model and a linear varying gain factor model—in their linear transfer function forms. A lumped conceptual model—the soil moisture accounting and routing model—was also applied to the sub-catchments and the basin. The HEC-HMS model, which is a distributed model, was applied only to the entire Kilombero River basin. River discharge, rainfall and potential evaporation data were used as inputs to the appropriate models and it was observed that sometimes the system models performed better than complex hydrological models, especially in large catchments, illustrating the usefulness of using simple black-box models in datascarce situations.  相似文献   

Flood forecasting and infiltration modeling/Prévision de crue et modélisation de l’infiltration     

《水文科学杂志》2013,58(2)

Abstract

Abstract The role of accuracy in the representation of infiltration on the effectiveness of real-time flood forecasting models was investigated. A simple semi-distributed model of conceptual type with adaptive estimate of hydraulic characteristics included in the infiltration component was selected. Infiltration was described by a very accurate approach recently formulated for complex rainfall patterns, or alternatively through a simpler formulation known as an extension of the classical time compression approximation. The results indicated that, for situations involving a significant rainfall variability in space, the inaccuracy in the representation of infiltration cannot be corrected by the adaptive component of the rainfall–runoff model. A preliminary analysis of the role of an approximation of saturated hydraulic conductivity to be used in each homogeneous area of the semi-distributed model used both in non-adaptive version and in real-time is also presented.  相似文献   

Trend detection in river flow series: 1. Annual maximum flow / Détection de tendance dans des séries de débit fluvial: 1. Débit maximum annuel     

《水文科学杂志》2013,58(5)

Abstract

Results of a study on change detection in hydrological time series of annual maximum river flow are presented. Out of more than a thousand long time series made available by the Global Runoff Data Centre (GRDC) in Koblenz, Germany, a worldwide data set consisting of 195 long series of daily mean flow records was selected, based on such criteria as length of series, currency, lack of gaps and missing values, adequate geographical distribution, and priority to smaller catchments. The analysis of annual maximum flows does not support the hypothesis of ubiquitous growth of high flows. Although 27 cases of strong, statistically significant increase were identified by the Mann-Kendall test, there are 31 decreases as well, and most (137) time series do not show any significant changes (at the 10% level). Caution is advised in interpreting these results as flooding is a complex phenomenon, caused by a number of factors that can be associated with local, regional, and hemispheric climatic processes. Moreover, river flow has strong natural variability and exhibits long-term persistence which can confound the results of trend and significance tests.  相似文献   

Pulse generation models for daily intermittent streamflows / Modèles de génération d’impulsions pour des débits journaliers intermittents     

《水文科学杂志》2013,58(3)

Abstract

Abstract Generating pulses and then converting them into flow are two main steps of daily streamflow generation. Three pulse generation models have been proposed on the basis of Markov chains for the purpose of generating daily intermittent streamflow time series in this study. The first one is based on two two-state Markov chains, whereas the second uses a three-state Markov chain. The third model uses harmonic analysis and fits Fourier series to the three-state Markov chain. Results for a daily intermittent streamflow data series show a good performance of the proposed models.  相似文献   

NP6-1井PDC钻头断落处理与认识     

褚道余  郝和伢 《海洋地质译丛》2012,(2):87-89

随着PDC钻头的广泛使用,因PDC钻头选型与钻遇地层的不匹配,或PDC钻头本身质量问题,也遇到一些井下复杂情况。此文介绍NP6-1井在311．2mm井段使用PDC钻头钻至井深2878．76m时,PDC钻头从公扣根部折断留在井底,加工公锥和采取适当措施成功地打捞出落鱼,避免侧钻,挽回了经济损失。该井成功打捞出PDC钻头,为同类型的井下落鱼或小落鱼提供参考与借鉴。  相似文献