Motion Regular Analysis and Its Simulation of the Rodless Drilling Unit's Guiding & Positioning Board

To analyze the stress of the guiding & positioning board and the effectiveness of the guiding & positioning device,according to guiding & positioning device's operational principle and structure,the guiding & positioning board's motion regular was analyzed by diagrammatical method based on 2 postulated conditions.Considering about the working conditions' change,simulations in 5 different kinds of working conditions were done to check the correctness of the motion regulars obtained by diagrammatical method.Simulation results prove that the motion regulars are right,the postulated conditions have no effect on the obtained motion regulars.According to the simulation results,the motion processs's characters were drawn out at the same time.

Modeling of Micropores Drilling Force for Printed Circuit Board Micro-holes Based on Energy Method

The quality of printed circuit board(PCB)micro-hole processing directly determines the stability of the inner and outer circuit connections.Micro-hole drilling technology is a typical method for PCB micro-hole processing.The problem of optimal control of its drilling force is one of the main factors affecting the quality of micro-hole machining.To address this problem,the thrust forces and torques in PCB drilling were first modeled and analyzed,and the corresponding prediction models were established.The drilling force analysis was carried out through the micro-hole drilling experiment,the specific cutting energy under different feed rates was calculated,the influence of the size effect was clarified,and the accuracy of the prediction model was verified.The result shows that during the drilling of glass fiber cloth,changes in the material removal mechanism are induced as the feed per revolution is varied.When the feed per revolution is less than the tool edge radius,the glass fiber is not cut by the main cutting edge,but is crushed and broken.When the feed per revolution is greater than the radius of the tool edge,the glass fiber is cut by the main cutting edge.At the same time,the established analytical model can accurately reflect the influence of the size effect on the drilling torque in PCB micro-hole drilling,and the error is within 10%.This method has certain practical application value in controlling PCB micro hole processing quality.

Investigations into the coiled tubing partial underbalanced drilling (CT-PUBD)technique for drilling hard formations

To improve the rate of penetration(ROP) in drilling deep and hard formations, this paper proposes a new drilling method called coiled tubing partial underbalanced drilling(CT-PUBD). As a preliminary investigation into the new drilling method, this paper presents predictions of hole cleaning efficiency, drilling speed, cuttings migration and pressure loss in the drilling process with CT-PUBD. Based on numerical simulation and full-scale experimental studies, we conclude that using CT-PUBD, an underbalanced drilling condition can be achieved near the bit while maintaining wellbore safety at the same time. This condition can be achieved using a cuttings discharge device, a rotary packer and a backflow controller.According to the numerical simulations performed in this study, CT-PUBD can achieve high efficiency of hole cleaning.Along the cuttings migration process, the fluid velocities can reach the maximum values in the backflow holes. A full-scale laboratory experimental system was used to test the hydraulic characteristics and obtain the drilling performance of the new technology. The result shows that CT-PUBD significantly improves the ROP compared to the conventional drilling method.

A Predictive Model of Enhanced Oil Recovery by Infill Drilling and Its Application

Infill drilling is now recognized as a viable improved recovery process. However, the reliable prediction of incremental recovery by infill drilling cannot be readily and accurately determined by present techniques. This paper proposes a hybrid predictive model of stream tube simulation and numerical simulation by using the contemporary theory of fluid flow in porous media. The model calculates the geometries of stream tubes, remaining oil distribution and water cut at different development stages in the near future, and uses a three-dimensional simulation to track fluid movement in each stream tube slice. This will help reservoir engineers to determine the feasibility of infill drilling. This predictive model is used to forecast the degree of control of well pattern, the ultimate incremental recovery of infill wells within an inverted 5-spot case in an oilfield and the economic benefit is also analyzed.

A solids-free brine drilling fluid system for coiled tubing drilling

There are many problems associated with coiled tubing drilling operations, such as great circulation pressure loss inside pipe, difficulties in weight on bit(WOB) transferring, and high probability of differential sticking. Aiming at these problems, solids-free brine drilling fluid system was developed on the basis of formulation optimization with brine base fluid experiment, which was evaluated and applied to field drilling. Based on the optimization of flow pattern regulator, salt-resisting filtrate reducer, high performance lubricant and bit cleaner, the basic formula of the solids-free brine drilling fluid system was formed: brine +(0.1%-0.2%) Na OH +(0.2%-0.4%) HT-XC +(2.0%-3.0%) YLJ-1 +(0.5%-2.0%) SDNR +(1.0%-2.5%) FT-1 A +(1.0%-5.0%) SD-505 + compound salt density regulator. Lab evaluation showed that the fluid had satisfactory temperature resistance(up to 150 ℃), excellent cuttings tolerance(up to 25%), and strong inhibition(92.7% cuttings recovery); Moreover, its lubrication performance was similar to that of all oil-based drilling fluid. The wellbore could be fairly cleaned at annular up-flow velocity of more than 0.8 m/s if the ratio of yield point to plastic viscosity was kept above 0.5. This fluid system has been applied in the drilling of three coiled tubing sidetracking wells in the Liaohe Oilfield, during which the system was stable and easy to adjust, resulting in excellent cuttings transportation, high ROP, regular hole size, and no down hole accidents. In summary, the solids-free brine drilling fluid system can meet the technical requirements of coiled tubing drilling.

考虑“筒中筒”耦合作用的深水隔水管柱与钻柱碰摩运动规律

深水钻井时,旋转钻柱与海洋环境力作用下发生振动的隔水管柱易发生接触,造成钻柱与隔水管柱的碰撞或者摩擦。为了解隔水管柱与钻柱间的运动状态,减轻两者间碰摩,保证作业安全性,提出了一种模拟深水隔水管柱-钻柱组成的“筒中筒”耦合系统模型,通过分析二者间的位移与接触力,实现海洋深水钻井作业时隔水管柱与钻柱的耦合动力学模拟的建立。模拟结果表明,考虑隔水管柱与钻柱接触的情况下,海流作用和涡激作用对钻柱的动力学特征具有较大影响;海流速度增加,隔水管柱弯曲程度变大,隔水管柱的振动特征会限制钻柱运动;井口转速增加对钻柱的涡动特征影响小,但会增大钻柱与隔水管柱内壁的接触力,增大钻柱与隔水管柱的失效风险。该理论为海洋深水钻井摩阻分析提供了新的借鉴。

钻井平台Tube管优化设计

钻井平台D90-Alfa是中集来福士为挪威D90深水公司建造的第七代钻井平台,是海工界先进产品的代表。Tube管是建造过程中施工最晚的管路部分,在船上的分布位置广、涉及区域多,其设计的合理性决定着施工的效率,制约着管路系统完整性的进度。文章通过该钻井平台的Tube管设计进行分析,总结出其设计过程的优点,为今后Tube管的设计提供参考。

岩心钻探振动拔管器的研制及在卡埋钻处理中的应用

卡埋钻事故是矿产资源勘查岩心钻探最难处理的事故,传统的强拉、强顶、强扭、反丝钻杆反取等处理方式,处理成功率均极低,且程序繁琐,耗时、耗力、耗成本。为解决卡埋钻事故处理难题,研制了振动拔管器。使用时,将该机具安装在孔口钻杆上,通电即产生高频高压振动,然后用钻机主卷扬向上提拉振动拔管器+钻杆连合体,通过提拔+振动联合作用,实现解除卡阻。振动拔管器坚固耐用、操作方便、成本低廉,在钻探现场应用处理卡埋钻事故数十次,成功率达90%以上,具有极大的推广应用价值。

垂直井内上击器解卡过程中钻柱振动数学模型的建立与求解及动态解卡力分析

对于油气井内解卡过程中的钻柱振动情况及动态解卡力,目前还没有有效的分析方法。该研究建立了垂直井内上击器解卡过程中考虑钻井流体阻尼的钻柱振动数学模型,并进行了求解,分析了几个主要因素对动态解卡力的影响。首先,介绍了上击器解卡过程中钻柱振动的三个阶段:(1)拉伸储能阶段,对钻柱进行静力学分析;(2)泄压阶段,结合拉伸储能阶段的计算结果,通过特征函数展开法与拉普拉斯变换求解了泄压阶段的钻柱振动数学模型;(3)撞击阶段,引入了将钻柱-钻柱轴向撞击的强非线性问题转化为多段钻柱振动的线性问题的求解思路,通过紧差分方法对撞击阶段的钻柱振动数学模型进行求解,获得了钻柱中的弹性波传播规律以及动态解卡力。其次,建立了与三个阶段相应的数学模型并求解。然后,采用该模型计算了无阻尼情况下的荷载场与动态解卡力,经低通滤波处理后的计算结果与相应条件下的解析解以及ABAQUS软件所得结果均有较好的吻合,验证了该工况下解法的准确性。最后,分析了震击启动拉力、上击器位置、钻井流体黏度、以及芯轴有效距离对动态解卡力的影响。所得结论对使用震击解卡的作业过程具有一定的指导意义。

一种月球熔岩管钻进的超声波钻探器

提出一种采用多点驱动旋转的螺旋槽圆锥复合型变幅杆结构,并研制了适用于熔岩管内壁钻进的高性能超声波钻探器;为预测超声波钻探器响应特性,利用等效阻抗网络模型对超声波钻探器进行了建模与分析。通过低重力多角度模拟钻进试验与数据分析,验证了该钻探器在熔岩管复杂地况应用中的可能性。结果表明,钻杆直径为3 mm、钻压力为10 N时,钻进速度随开孔角度的增加而增加,垂直钻进时钻探器最大空载回转速度为506 rad/min,钻进速度为6.4 mm/min,钻进时回转转速为259 rad/min。

C型开口聚能管爆破机理与隧道光爆优化效果研究

超欠挖是钻爆法隧道施工的常见问题,与光面爆破效果密切相关。为有效解决隧道掘进超欠挖及常规聚能管不利于光爆层岩体破碎的问题,以优化调节爆轰能量为思路,采用理论分析和数值模拟方法研究C型开口聚能管的裂岩机理。研究结果表明采用C型开口聚能管与采用常规聚能管和常规药包的光面爆破相比具有以下显著优势:1)聚能管开口能显著提高光爆层岩体应力,使光爆层岩体率先损伤,引导岩体充分破碎;2)开口的存在间接增大了聚能方向上的拉应力,裂纹沿聚能方向定向扩展,超欠挖控制效果良好;3)与常规聚能管相比,非聚能方向的岩体应力降低更多,裂纹拓展更少,这更易于保护开挖轮廓线外侧围岩;4)C型开口聚能管可提高周边孔孔距和光爆层厚度,有利于提高光面爆破的效果;C型开口聚能管与常规爆破相比,超挖量降低83%,欠挖量降低68%,半孔率更高且开挖轮廓更平整,并可在一定程度上降低钻孔量和炸药单耗。总体上,C型开口聚能管的应用有利于提高隧道钻爆法施工的效率和质量。

深水海底连续管钻机起升系统设计与仿真研究

以深水连续管钻机为对象,针对连续管钻机不能下套管的问题,设计了一种以液压绞车、钢丝绳和滑轮组合且与连续管钻机集成的起升系统。该系统在保证深水连续管钻井作业的同时,还能够实现下套管作业。构建了起升系统的三维模型,建立了深水连续管钻机的作业流程;给出了关键部件的设计参考并进行验证,以保证系统的安全性;并针对不同作业工况,基于ADAMS进行了起升系统的动力学仿真,分析了连续管钻机的运动特性及钢丝绳的受力,验证了起升系统的运动和动力学特性。设计的深水连续管钻机起升系统具有结构紧凑、连续起下的特点,相比传统钻机在深水浅层作业时更有优势,对后续深水钻机的研究具有实际意义和参考价值。

非开挖拖拉管在市政污水处理中的施工与应用

基于市政污水管道的特点采用非开挖法,并对非开挖技术进行深入分析后选用非开挖拖拉管的方式进行污水管道施工,根据对拖拉管线定位探测方法分析最终选择了水平定向钻技术,最后对非开挖拖拉管在施工过程中容易出现的问题进行技术分析,并提出相应的控制措施。

城市轨道交通隧道综合岩溶勘察技术创新应用

为控制岩溶发育地区城市轨道交通工程施工过程中的地质风险,准确查明隧道洞身区域岩溶发育程度及特点至关重要。若仅采用在隧道结构线外侧实施钻探的方法,存在隧道范围内岩溶无法准确查明等不足。针对此问题,以贵阳市城市轨道交通3号线一期工程区间隧道为例,针对不同平面位置、深度岩溶的发育特点,在调查获取相关勘察资料基础上,采用地质雷达、微动、高精度瞬变电磁等地面物探方法,逐步圈定岩溶发育的重点区域,再通过在隧道中线位置实施钻探进行验证,并对溶洞充填物进行原位测试及室内试验,最后利用钻孔开展跨孔CT和管波测试。物探推断197处岩溶发育,有34处与钻孔揭露溶洞相吻合,70%的洞径小于2 m;94%溶洞分布于底板埋深以上,其中29%分布于隧道洞身范围内;55%以上钻孔揭露溶洞为无充填类型。本次岩溶勘察查明了岩溶类型及形态、岩溶空间分布特征、岩溶与隧道结构关系、溶洞充填情况等信息,为该项目设计施工提供翔实、准确的地质资料。

凹形地貌水下爆破减振技术研究

为深入探究凹形地貌水下爆破时减振孔的不同参数对地表震动所产生的影响,结合广州的某一沉管隧道基槽开挖工程,借助LS-DYNA对水下钻孔爆破展开模拟计算。着重研究了在凹形地貌水下钻孔爆破进程中,减振孔的位置、排数、深度以及距离对于河岸地表的质点峰值振速PPV(Peak Particle Velocity)和减振率的影响状况。研究结果表明,河岸地表振动是水击波和地震波协同作用的结果,水击波对河岸震动起主导作用;减振孔布置在爆源附近基本没有减振效果,布置在监测点周围时减振率为26.6%,被动隔离比主动隔离更适合凹形地貌水下爆破;地表测点的PPV随着减振孔排数的增大呈减小趋势;增加减振孔的深度能够显著提高减振率,但提升效果有限,建议工程上采用浅孔多排布置方式;减振率随着减振孔离河岸的距离的增加先增大后减少,减振孔距离河岸2.5 m时,减振效果最好。

连续管钻井个性化PDC钻头降扭机理及试验研究

由于连续管自身管径小、柔性大等特性,在进行井下钻进时容易导致摩擦自锁和管柱屈曲,存在钻压施加困难、进尺低下等问题。为提高连续管在低钻压情况下的钻进能力,个性化设计了连续管钻井专用小尺寸PDC钻头。通过单齿切削试验、水平井钻柱微钻头破岩试验、全钻头破岩试验开展小尺寸PDC钻头的降扭机理研究,对比不同齿形对破岩效果的影响。研究结果表明:在PDC切削齿前倾角较小时,破碎相同体积的岩石,宽刃齿所受切削力平均值比常规齿小10.35%~24.56%;同机械钻速情况下,宽刃齿钻头的扭矩小于常规齿钻头,最高降扭37.64%;同转速和钻压情况下,宽刃齿钻头最高降扭28.58%,钻压越大,降扭效果越显著。个性化设计的宽刃齿PDC钻头更适用于连续管实现低钻压、低扭矩、高转速破岩。研究结果可为改善连续管钻井技术在低钻压钻进时的适应性提供新的解决思路和理论支撑。

深层页岩气连续油管钻磨桥塞技术

随着川渝地区页岩气开发迈向深层,连续油管钻磨桥塞面临深层页岩气井口压力高、套变导致卡钻、频繁起下易导致油管失效等复杂工程,严重影响到连续油管在深层页岩气改造后钻磨的作业安全和时效。通过开展连续油管钻磨桥塞难点分析、适用于川南深层页岩气区块的变径连续油管结构优化、高温环境下循环用钻磨工作液体系优化、高压下钻磨桥塞工艺优化等方面的研究,形成了满足川南深层页岩气井的连续油管高压钻磨桥塞关键技术和配套工艺措施。经川南页岩气区块现场应用84井次,卡钻等复杂情况由前期5.3%下降至3.3%,钻磨桥塞由前期的3~5趟钻缩短至1~3趟钻,安全快速地实现了压裂后的井筒清理,缩短了钻磨桥塞的时间,提高了作业效率。该技术为川南深层页岩气安全高效开发提供了技术支撑。

钻机动力头芯管断裂失效分析

针对钻机动力头芯管在施工过程中易出现断裂失效的问题,对断裂芯管进行了化学成分检验、断口宏观分析、受力和有限元仿真分析、金相组织和扫描电镜微观组织分析研究。结果表明,断裂主要由于芯管受到来自主轴和配油套旋转运动产生的弯曲应力,芯管材料许用最大弯曲应力小于极限工况下受到的弯曲应力,产生纤维状裂纹、最终断裂。其他因素导致的频繁微小冲击也会降低芯管的使用寿命,导致疲劳断裂失效。试验通过优化热处理参数、更换新材料的方式,增加了芯管连续工作不出现断裂和变形的时间,提高芯管使用寿命。

某钻井工具探管开裂原因

某钻井工具探管发生横向开裂现象,采用宏观观察、化学成分分析、硬度测试、金相检验、扫描电镜和能谱分析等方法对探管的开裂原因进行分析。结果表明:探管材料为奥氏体不锈钢,服役环境中的氯离子为其应力腐蚀提供了腐蚀环境,探管在钻进过程中承受轴向应力,加上制造过程中探管产生的残余应力,这些因素均为探管发生应力腐蚀开裂提供了力学条件,最终导致其发生氯化物应力腐蚀开裂。

水平井连续油管带压钻塞技术的研究及应用——以HN油田XX凹陷为例

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