基于泥包最小化的PDC钻头水力参数优选  

Selection of PDC Bit Hydraulic Parameters based on Minimal Balling

作　　者：陈修平 邹德永 

机构地区：[1]中国石油大学,山东青岛266580

出　　处：《特种油气藏》2014年第4期142-144,158,共3页Special Oil & Gas Reservoirs

基　　金：国家"十二五"科技重大专项"胜利油田薄互层低渗透油田开发示范工程"子课题"薄互层水平井导向PDC钻头优化设计及导向特性研究"(05Z12020300)

摘　　要：PDC钻头在泥页岩地层中钻进时,如果水力参数选择不当,极易形成泥包,严重影响钻井效率。现有水力参数优选标准并不适用于PDC钻头,且对特殊工况(如钻头泥包)没有针对性。为此,在对PDC钻头泥包机理及井底水力性能对其影响规律分析的基础上,推导了井底岩屑输运率公式,建立了基于泥包最小化(井底岩屑输运率最大化)的PDC钻头水力参数优选标准,给出了水力参数优选步骤,并进行了实例应用分析。研究发现:输运岩屑的能量主要来源于井底漫流水功率;无论是原始泥包还是二次泥包,提高井底岩屑输运效率,都能够预防或减少PDC钻头泥包现象。PDC bit balling may easily occur when drilling in mud shale formation if hydraulic parameters are not selected properly,thereby greatly affecting the drilling efficiency. Current standards for selecting hydraulic parameters are not applicable for PDC bit,and have not address some special work conditions,such as bit balling. Therefore,through analysis on PDC bit balling mechanism and the influence of bottomhole hydraulic performance,a formula for bottomhole transportation rate of cuttings is derived,standard for selection of PDC bit hydraulic parameters based on minimal balling(or maximal bottomhole transportation rate of cuttings) is established,and the selection procedures for hydraulic parameters are given. Case study is made,indicating that the energy for cuttings transportation mainly comes from overflow water power at the bottomhole; the increase of transportation efficiency of bottomhole cuttings can prevent or reduce the PDC bit balling,either primary balling or secondary balling.

关 键 词：PDC钻头 水力参数优选 泥包 岩屑输运 漫流水功率 

分 类 号：TE21[石油与天然气工程—油气井工程]