水平井钻井合理环空返速的确定方法

DESIGN METHOD OF REASONABLE ANNULAR VELOCITY IN HORIZONTAL DRILLING

根据我国水平井钻井水力参数设计与施工中存在的问题，提出了以有效携岩为目的来确定水平井三个洗井区合理环空返速的方法．在第一洗井区，利用垂直二相流控制方程式作为依据来确定用于安全携岩的环空返速；在第二洗井区，采用环空止动返速作为合理的环空返速，并对影响环空止动返速的诸因素进行了分析，在第三洗井区，运用理论研究成果提出了确定合理环空返速的一般步骤，最后利用本文所述方法列举了一口水平井水力参数的设计实例．

A method for determining annular velocity in three regions of hole cleaningfor solving some problems emerged in design and operation in horizontal drilling hydraulicparameters with the purpose of effective transporting cuttings is presented. In the firstregion,the control equation for Isolid- liquid flow in annulus is used to determine the annularvelocity for transporting cuttings safely,In the second region,annular unslided velocity isused as reasonable annular velocity and the factors affecting the annular unslided velocity isanalysed.In the third region,the paper gives the steps to determine reasonable annularvelocity by the use of the achievements in theoretical research.Finally,an example fordesigning horizontal drilling hydraulic parameters is introduced.