库车山前地区抗钻特性及钻头优选技术研究

发布时间：2018-06-10 06:57

本文选题：山前构造 + 地层抗钻性参数　；参考：《长江大学》2015年硕士论文

【摘要】：库车山前构造是中石化的重点勘探开发区块,作为加快中国西部油气建设的重要生力军,具有广阔的开发前景。但随着我国在西部油气的勘探开发力度不断增大,开发难度和工况也日益复杂。实践表明,在新疆塔里木盆地区块的钻井过程中遇到的困难较多,主要表现为地层抗钻性高、机械钻速低、钻井周期长等。因此,努力提高机械钻速、提高钻井效率、缩短施工周期,对山前构造地区能源的高效动用具有重大现实意义。本研究依托中石化石油工程先导和推广项目“库车山前地区安全优快钻井技术研究”,立足于库车山前地区复杂地质条件,针对山前构造在勘探过程中普遍存在的钻头失效快、钻井速度慢等难题,深入研究了山前构造地区的地层抗钻特征,总结出了地层抗钻性规律；从力学角度出发,细化分析破岩工具的力学行为,结合现场实践,对破岩工具进行了优化选型；并引入针对性设计概念,结合理论模型研究,设计出了适应山前构造复杂地层的破岩工具,最终形成了一套适合山前构造地区的提速方案。其主要的研究成果如下：(1)在用常规室内微钻头法建立地层可钻性级值计算模型的基础上,利用地层岩石硬度的测试仪分析了声波测井与岩石硬度之间的数学关联,考虑了岩石硬度在分析库车山前地区地层抗钻性研究中的影响,建立了适合库车山前构造地层岩石抗钻性的计算模型,通过试验测试分析了库车地区整体地层抗钻性规律,并以此绘制了库车山前地区的地层抗钻特征规律分布图。经分析库车山前地区地层可钻性级值和地层岩石硬度整体上是随着地层深度的不断加深而不断增大,但是在第四系地层和吉迪克组地层以及以下白垩系地层的可钻性级值和硬度的变化波动幅度较大,第四系地层的可钻性级值变化范围在1-6之间,地层岩石硬度在10-500MPa之间,吉迪克组及以下白垩系地层可钻性级值变化范围在3.5-6之间,地层岩石硬度在250-1000MPa之间。(2)从力学角度研究分析了牙轮钻头和PDC钻头的受力情况和破岩机理,结合对地层抗钻特性规律的研究及对库车山前地区的地质情况,总结出了库车山前构造地区钻头的应用范围及使用特点,并以此深入分析适用于库车山前地区的钻头选型理论,立足此理论完成了对库车山前地区的钻头选型,形成了一套适合库车山前构造地区的钻头序列。第四系地层由于砾石层较厚,地层抗钻性强,多采用牙轮钻头；库车组及吉迪克组地层,地层多以泥岩为主,地层抗钻性较好,适合底部动力钻具配合PDC钻头进行钻进,推荐使用刀翼数少,布齿密度低的钻头；吉迪克组以及苏维依组地层由于地层含有大段盐膏岩,在实际的钻头使用中,效果并不理想,但由于该地层整体硬度较上部地层差异不大,且在刚进入吉迪克组时地层硬度有明显的降低趋势,则在钻头的选用上依旧选用5刀翼钻头,以保证钻头的攻击性,考虑到地层可钻性的较差,则降低钻头的切削齿尺寸,由19mm降为16ram,以提高切削齿的使用寿命；白垩系地层由于地层抗钻性差,地层的研磨性明显提高,地层夹层较上部地层明显增多,地层岩性变化大,在钻头的选用上应选用有高耐磨齿的钻头,如深远DFS1605U钻头在该层位有较好的表现,平均机械钻速为2.05m/h,较普通PDC钻头机械钻速提高了49%。(3)根据已钻井复杂地层的钻头使用情况,综合分析了第四系巨厚砾石层以及吉迪克组大段盐膏层的钻头使用特点,对上述复杂地层的钻头进行了优化设计：第四系地层主要采用牙轮钻头,通过改良钻头喷嘴,强化掌背、优化齿形,以提高钻头在第四系地层的破岩能力；分析研究PDC钻头设计理论,针对PDC钻头在吉迪克组及以下地层的使用过程中普遍存在牙齿攻击性不强,抗冲击性差等问题,从切削齿、刀翼、冠部、保径这几个方面入手,设计出了一个16mm切削齿,5刀翼,中等抛物线冠型,中等密度布齿的T1653钻头,在库车2井现场使用,并取得了较好的应用效果。通过以上研究取得的成果,对库车山前构造及地层特性有了一定的认识,形成了一套钻头优选方案,为以后该地区的钻井施工提供一定的指导作用。
[Abstract]:The construction of Kuqa mountain front is the key exploration development zone block of Sinopec , which is an important force for accelerating the oil and gas construction in western China . It has broad prospects for development . However , as China ' s exploration and development of oil and gas in the west is increasing , the development difficulty and working condition are more complicated .
Based on the mechanical angle , the mechanics behavior of rock breaking tool is analyzed , and the rock breaking tool is optimized and selected in combination with the field practice .
Based on the analysis of the influence of rock hardness between 1 and 6 , the rock hardness of the formation is varied from 1 to 6 , the rock hardness of the formation is between 1 and 6 , and the rock hardness of the formation is between 10 and 500 MPa .
The strata of Kuqa Formation and Jik Formation are mostly mudstone , and the stratum has better anti - drilling property . It is suitable for drilling with PDC bit in the bottom dynamic drilling tool , and it is recommended to use a bit with low number of blades and low tooth density .
Because the formation contains large - segment salt paste , it is not ideal in the actual drill bit . However , because the overall hardness of the formation is less than that of the upper stratum , and the formation hardness is obviously decreased when it comes into the Godik group , 5 - blade bit is still used in the selection of the drill bit , so as to ensure the aggressive of the drill bit , and the cutting tooth size of the drill bit is reduced , and the cutting tooth size of the drill bit is reduced from 19 mm to 16 ram , so as to improve the service life of the cutting tooth ;
In this paper , the characteristics of the bit used in the strata with high wear - resistant teeth , such as the deep DFS1605U bit , have been improved obviously , the average mechanical drilling speed is 2.05m / h , the mechanical drilling speed of the common PDC bit is improved by 49 % .
This paper analyzes the design theory of PDC bit , and designs a 16 mm cutting tooth , 5 blade , medium parabola crown type , medium density cloth tooth T1653 drill bit , which is used in the field of Kuqa 2 well and obtains better application effect from several aspects such as cutting tooth , knife wing , crown and keeping diameter .
【学位授予单位】：长江大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TE921.1;TE24

【参考文献】