定向井井眼轨道预测方法研究及其应用

对定向井片眼轨道进行预测是实现井眼轨道定量控制的关键.本文提出了井眼轨道预测控制的力-位移模型.在此基础上,建立了描述侧向切削问题的多元幂积模式,推导了预测井斜、方位及其变化率的基本预测公式,形成了井眼轨道预测控制系统,并进一步研制了适于井场快速预测的自适应信号跟踪顶测软件,针对IBM-PC微机,开发了定向井井眼控制预测软件包DTCPS.多例预测实践表明,使用该软件包预测井眼轨道,精度较高,相符程度较好.

AN ANALYSIS AND VERIFICATION OF FORMATION FORCE FOR CONTROLLING BIT TRAJECTORY IN DIRECTIONAL DRILLING

Predicting the inclination and azimuth is a key issue of the bit trajectory quantitatively controlling in directional drilling.A new model of predicting and controlling the bit trajectory,named as Force-Displacenlent.Model,is presented in this paper.A mathmatical model for side cutting is established in terms of a product of powers of several related parameters,including side force on the bit,pene.traticam rate,penetration interval,bit r.P.m and rock strenghth index,etc.A set of basic equations for predicting the changes of inelinatiom azimuth build-up rate and walk rate are derived.Futhermore,a prediction and control system is formed.A prediction program with self-correcting,feedback and tracking ability is studied.The DTCPS,a directional drilling software package for predicting and controlling the bit trajecti}ry,is developed for an IBM-PC computer.Examples of field prediction of inclination and azimuth in directional drilling are 9iven in this paper.They indicate good agteement between theotetical predietion curves and the measured data.