模拟下套管技术在河坝区块大斜度井中的应用

为解决河坝区块大斜度定向井在实钻过程中由于井眼轨迹不规则、盐膏地层缩径，大斜度井段下套管作业的实际难题，在调研大斜度井下套管方法的基础上，结合河坝区块大斜度井特点，建立了井眼、套管相容性模型并总结出下套管过程的模拟步骤：①依据收集的实钻井眼资料，计算套管串和井眼两种最小曲率半径，分析无接箍套管能否下入井眼；②针对实际套管接箍或扶正器尺寸，以实钻井眼数据反算出允许通过的套管串的不变形长度；③分析不同管串所对应的不变形长度与井眼曲率的关系，然后确定出与套管柱刚度相当的通井管柱结构。模拟下套管技术在HB1 1D等井的成功应用，为大斜度井现场模拟下套管提供了理论依据。

Application of casing running simulation in highly deviated wells at the Heba block

When drilling high angle directional wells at the Heba block, the casing running operation often becomes problematic at high angle sections due to the irregular trajectory and undergauged gypsum section. Based on the investigation of the casing running methods for high angle wells, and in combination with the features of high angle wells at the Heba block, a wellbore casing compatibility model is set up, and the casing running simulating procedures are summarized as follows: a. to calculate the minimum radium curvature of casing string and the wellbore according to the collected drilling data, so as to determine whether the no coupling casings can be run downhole smoothly or not; b. to get the maximum allowable length of undistorted casing string through reverse calculation from the actual drilling data, with the sizes of the casing couplings and centralizers to be actually used considered; and c. to decide the drifting assembly configuration which has a rigidity equivalent to that of the casing string, based on the analysis of the relationship between the undistorted length and the welbore curvature. The successful application of this simulation at the well HB1 1D has provided a theoretic evidence for the simulation of casing running in high deep wells.