分支井论文.doc

摘要 (直井、定向井、水平井)中钻出若干进入油（气）藏的分支井眼。分支井在海上油田和陆上油田在垂直方向上有多个产层，薄油藏及稠油油藏等方面应用越来越普遍。由于分支井一般都是三维井身剖面，并且分支井的起点位置位于主井筒上，其设计方法不同于普通定向井和水平井，有必要研究新的轨迹设计模型和设计方法。 分支井筒的设计需要确定分叉口处的坐标和井斜方位的井身参数，本文推导了用于井眼轨迹上任意一点确定井身参数的插值方法。分支井轨迹设计中涉及到主井筒和分支井筒的设计，本文在分析总结现有的各种定向井设计方法的基础上，对三维分支井轨迹设计做了详细的研究，并应用空间斜平面上的圆弧轨道设计方法，进行了详细的模型分析和理论推导，最终得出了一套实用的三维分支井的设计理论和方法。在理论设计的基础上，运用VB编程语言编制了分支井轨迹设计软件。 运用此方法和编制的软件用油田实例参数进行了验算，得到该井主井筒和一组分支井筒的轨迹分段数据，并对结果进行了离散，运用Excel作图得到了三维轨迹的垂直剖面图和水平投影图，由此验证了该方法的可靠性。 关键词：分支井； 轨迹设计； 最小曲率法； 斜平面法 Abstract Multilateral Wells is a kind of wells that are drilled several branches into the reservoirs from the main borehole which refers to vertical wells, directional wells, horizontal wells and etc. Multilateral Wells are widely used in the offshore oilfields and onshore fields to develop particular reservoirs such as the reservoir with several layers in the vertical direction, thin and heavy oil reservoirs. Since the well profiles are generally 3D and the kop locates in the main borehole, the well profile plan process is different from the ordinary directional wells and horizontal wells, it is necessary to study the new trajectory planning model and methods. The well plan of branches needs to determine the coordinates, inclination and azimuth of the tie-on point firstly. In this paper, the interpolation method for determining the trajectory parameters was developed. Well trajectory plan involved to the design of the main borehole and the branches. This paper summarized the various existing directional wells design methods based on the 3D trajectory design, a detailed study and application of space oblique plane circular orbit design method for a detailed analysis and theoretical model derived, finally a practical 3D multilateral well design theory and method were gained. On the basis of theory of well plan, multilateral well trajectory plan software was developed using VB programming language. Using this method, and software, a multilateral well form oilfield were planed, trajec