In drilling high angle deviated holes , friction is the main factor affecting the effective wob 在大斜度定向井钻井过程中，摩擦阻力是影响有效钻压的主要因素。
Well trajectory for non - straight wells , which includes directional wells , horizontal wells , siedtracking and / or horizontal wells , long - reach wells and multibranches , is one of key techniques in non - straight drilling . the main results , obtained in this dissertation , may be summarized as follows 本文以石油工程中的非直井(定向井、水平井、侧钻井、侧钻水平井、大位移井、分支井)轨迹控制为背景，研究了一类约束优化与最优控制问题。
The results of reserch work show that the area of ca012 , ca031 , ca060 and the area near the shi - cun faultage are adventage exploratory targets . the succeed possibillity is bigger . but it has the high venture in all . it is suggested to frac - pack , to drill directional well to test oil in steam stimulation 研究结果表明：位于火山口附近的草12井区和草31井区、草60井区、石村断层附近是比较有利的勘探目标，勘探成功的可能性较大，建议利用压裂引效、钻定向井的方法进行热采试油，并开展全区测井约束地震反演，对油气成藏进行更全面的评价。
