钻探参数数据智能采集系统的研制

详细介绍了最新研制成功的智能钻探测控数据采集系统的设计原则、技术特点、结构、参数设置方法以及测试应用情况.     

空气定向水平井钻进注气量试验研究

通过对空气正循环水平井的注气量进行实验研究,得出实际注气量应是满足关键点处最小动能时,将井底理论计算压力扩大17倍以后所对应的注气量,这对实际钻井前的设计有很好的指导作用。     

天津地区地热钻井及成井技术

多年来,天津地热钻井技术不断发展。天津市地热井施工最深达4041 m,最高井口温度105 ℃,自流水量300 m3/h。针对天津地区不同热储层的钻井工艺技术进行简要介绍,并总结了一些经验教训。     

黄金坪水电站深厚覆盖层跟管钻进工艺研究

结合大渡河黄金坪电站深厚覆盖层帷幕灌浆试验项目需要,对深厚覆盖层跟76 m深套管护壁钻进这一高难度技术进行攻关研究,并提出两级跟管的钻孔结构,圆满实现了试验灌浆孔非灌段跟76 m深套管的目标,为今后类似工程跟管施工提供了重要的参考借鉴作用。     

陕北浅层石油钻井的固控问题

通过计算对比，说明钻井过程的钻屑量，泥浆泵与钻杆的级配问题及钻井过程团相含量高的危害，对固相含量的要求，提出控制固相含量的措施等。     

南极冰层电缆式机械取芯钻进

介绍了南极冰钻的科学意义以及世界各国如原苏联、美国、法国、丹麦等国家施工冰钻的情况；重点阐述了俄罗斯南极冰钻的先进技术以及所采用的КЗМС－１１２型电缆式机械取芯钻具的结构和施工工艺。     

复合片钻头钻进时机械钻速和碎岩功耗的研究

关于复合片钻头钻进大理岩和花岗岩时机械钻速和碎岩功率消耗同规程参数的关系,用实验设计方法进行了试验研究,得出了机械钻速和碎岩功耗与钻压、钻头转速及冲洗液量关系的数学模型;提出了碎岩绝对功耗和相对功耗的概念,而相对碎岩功耗是个更为重要的概念,求出了大理岩相对碎岩功耗最小时的最优钻进规程参数值。     

群库恰克地区井壁失稳影响因素的研究

群库恰克地区钻井复杂事件统计表明,群6、群601及群7井中共发生各类复杂事件129次,严重影响了钻井工程安全和工程进度。对此问题,通过分析失稳井段岩石矿物组分与岩石理化的情况并结合实际钻探中遇到的问题,研究了井壁失稳的主要影响因素,并分析了钻井液在钻探过程中所起的作用及其重要性,为该地区井壁稳定技术的研究提供了合理的依据。     

Response of rigid piles during passive dragging

This paper develops a three‐layer model and elastic solutions to capture nonlinear response of rigid, passive piles in sliding soil. Elastic solutions are obtained for an equivalent force per unit length p_s of the soil movement. They are repeated for a series of linearly increasing p_s (with depth) to yield the nonlinear response. The parameters underpinning the model are determined against pertinent numerical solutions and model tests on passive free‐head and capped piles. The solutions are presented in non‐dimensional charts and elaborated through three examples. The study reveals the following:

• On‐pile pressure in rotationally restrained, sliding layer reduces by a factor α, which resembles the p‐multiplier for a laterally loaded, capped pile, but for its increase with vertical loading (embankment surcharge), and stiffness of underlying stiff layer: α = 0.25 and 0.6 for a shallow, translating and rotating piles, respectively; α = 0.33–0.5 and 0.8–1.3 for a slide overlying a stiff layer concerning a uniform and a linearly increasing pressure, respectively; and α = 0.5–0.72 for moving clay under embankment loading.
• Ultimate state is well defined using the ratio of passive earth pressure coefficient over that of active earth pressure. The subgrade modulus for a large soil movement may be scaled from model tests.
• The normalised rotational stiffness is equal to 0.1–0.15 for the capped piles, which increases the pile displacement with depth.

The three‐layer model solutions well predict nonlinear response of capped piles subjected to passive loading, which may be used for pertinent design. Copyright © 2016 John Wiley & Sons, Ltd.