高密度油基钻井液在小井眼钻井中存在环空循环压耗、抽汲压力、激动压力高等现象,致使压力敏感地层钻井时溢、漏频繁,严重影响作业安全.文章以TF2井?149.2 mm井眼火山岩地层钻井为例,针对高密度油基钻井液内摩擦力大和井眼小、井深的特点,分析了在不同工况下井底压力骤变而带来的工程技术风险,提出了变密度控压钻井的技术思路:在不同工况下因循环压耗、抽汲压力、激动压力的变化影响而调整对应的钻井液密度和控制一定的井口压力来实现全作业过程中的井底压力略大于地层压力、保持井筒不溢不漏或微漏的一个状态,确保作业全过程的井控安全.文章对钻进循环、停泵、起钻、下钻4种工况下钻井液密度确定和井口附加压力调节给出了原则和控制条件,并在应用中对TF2井的地层压力、漏失压力、不同工况下的密度值进行了求取.该井应用变密度控压钻井技术,实现了在?149.2 mm小井眼中239.83 m的安全进尺,该项技术为类似复杂井的处理积累了宝贵经验.

随着工艺技术的不断成熟,卧龙河区块水平井钻探的工艺技术水平也有了明显的提高,但在钻井提速方面仍有一定的提升空间。本文通过对卧044-H2井钻井提速进行深入分析,详细阐述了卧044-H2井提速成果,并对下一步卧龙河区块钻井提速的对策进行了探讨。

页岩气藏为致密的非常规气藏,国外在页岩气钻采上取得了较好成绩一我国的页岩气资源丰富,开发利用页岩气资源具有广阔的前景,但国内页岩气藏的研究程度和认识程度都很低,目前仅在四川的长宁、威远地区进行了页岩气实验性勘探.由于页岩气资源多属于低渗透致密地层,常规钻进产能低,经济效益差,不能形成工业规模开发利用,为了提高产能,将以大斜度、长段水平井勘探方式为主.文章通过对威远、长宁区块地质特点的研究,采用了以理论为基础,与实钻资料统计分析相结合的研究方法,对蜀南区块页岩层大斜度水平井钻井技术进行研究,形成包括直井段快速钻进技术、钻井液体系研究及性能控制、防垮塌技术等相关技术体系,有效减少威远、长宁区块页岩气井钻井的事故复杂,缩短了页岩气钻井周期,有助于安全钻进和提高钻井速度,降低钻井成本,对开发利用页岩气等低效资源具有现实意义.

Due to the wellbore trajectory changes caused by directional drilling for Well Long 114,the tripping frictional resistance was increased,and it was difficult to draw the BHAout,resulting in the BHAexpansion and dropping into the well bottom during back reaming the wellbore.The fish length was 3 205.21 m,and the internal thread swelled and was deformed.Through analyzing the difficulties during accident treatment,the fishing tool was selected and improved.According to the handling program for the accident,the active stuck freeing strength was controlled within the force of thread making position of the fishing tool,and the fish was successfully tripped out finally.The idea and technical treatment can be helpful to the similar type of accident treating.

Highly deviated and horizontal wells are the key factor in the successful development of shale gas.The shale gas reservoirs in Weiyuan region form is in very complex conditions.Several situations exist at the same time,such as leakage,blowout and borehole collapse.And they make the drilling cycle too long.Because most of shale gas resources are low permeability tight formations,compared with conventional gas reservoirs,there is more difficult and challenging in development work.How to optimize the drilling casing program,and effectively reduce the risk of the shale gas drilling in Weiguan region,is currently a difficult problem.So,based on the original theoretical design,combined statistical analysis with the actual drilling research method,this paper puts forward the optimization design of casing program for Weiyuan structure.

Managed pressure drilling technique with mud-cap which normally takes water as the drilling fluid is usually used to solve challenging drilling job with harsh problems such as lost circulation, blowout and collapse. This requires that the formation to be drilled would be stable. Severe lost circulation has been encountered during the drilling in Well Wei 201-H3 at the depth of 1044.24m. And this severe lost circulation caused the drilling fluid height in annulus dropped down and caused severe overflow show. Because the well section in Longtan group drilled and Long-ma-xi group to be drilled are both collapse formation, the following drilling job would face complex situation such as lost circulation, blowout and collapse problems. In order to make the drilling success under so complex situation, two techniques have been used successfully. The first one is taking the mud-cap and "hangs mudding off" techniques to keep drilling fluid level, to balance gas formation pore pressure in upper well section and stabilize the prone-to-collapse formation. The second one is using composite-salt macromolecule anti-collapse drilling fluid to drill to the cementing depth. Mud-cap managed pressure drilling technique had the advantages of safe, rapid and low cost, and extended its application scope.

Shale gas resource is becoming the focus of oil & gas resource development because of the depletion of conventional resources. Several factors are the obstacle to the industrialized development for shale gas such as long production cycle, low per-well production, rapid depletion of output, slow fund recycle and environmental pollution. Horizontal well technologies are one of the key factors of successful shale gas development and accelerate the development process. Based on the field experiences in Well Wei 201-H1, the first shale gas horizontal well in Longmaxi formation in Weiyuan structure, some key relative technologies have been discussed in this article and would supply technique backup for the drilling planning and technology development in the area.

微泡钻井液是把某些表面活性剂与聚合物结合在一起产生的一种由各种组分组成、具有高强度气核壁、稳定性好的电子壳状空气气核微泡,这种微泡具有“一核二层三膜”结构.这种非聚集、可循环使用的均匀刚性气核体系在使用时,不仅可以维持钻井液的连续相特性、实现钻井液密度的还原,还能阻止或延缓钻井液进入地层,建立起一个真正非侵入、近平衡环境.该钻井液连续相特性能保证井下无线随钻仪脉冲信号的正常传输,密度范围可控制在0.80 ～1.50 g/cm3之间,使其成为低压低渗、易漏地层和储层保护的理想钻井液.磨80 -C1井是川渝地区第一口采用微泡钻井液技术并取得成功的水平井.文章介绍了微泡钻井液的配制和性能特点,分析了对井下无线随钻信号脉冲的影响程度.现场应用标明,该钻井液连续特性强,性能稳定,配伍性好,不会在井壁形成外滤饼,抗温达100℃,特别适用于低压低渗和易漏地层.

Rotating casing cementing technology can increase effectively the displacement efficiency of slurry,thus raising the cementing quality.But there exists high risk.The casing hanger may be worn in rotation leading to ineffective seal.Casing of Ф177mm is adopted for cementing of LG163 well at the depth of 2370m of Xujiahe Formation.By this technology,the drifting and casing string design,casing running can be completed successfully.By a centralizer installed between landing joint and casing hanger,the hanger and casing head can be effectively sealed.By the control of casing rotating torque,the construction safety can be ensured.Its first application to LG163 well indicates that the cementing is qualified and the high quality ratio reaches 73.5%.It has been widely used in Sichuan and Chongqing areas.

Network database used for the data management in each industry in China has gained widespread popularity and application, and greatly promote the industry's technological progress. The drilling field also was developed a number of databases, but remained on the simple inquiry and output part statistical reporting level, and the role of the database wasn't really played. Through the analysis of the problems existing in the application of drilling database at present, this article put forward the ideas that built drilling remote decision-making system by using the drilling database and advanced drilling engineering calculation software at home and abroad, as well as drilling knowledge base concordance. So, the drilling database and the introduced the engineering calculation software could fully give play to their functions, improve the level of management and operation of the drilling company, it provided a better service for the petroleum and natural gas exploration and development research.