六段制三维水平井轨道优化设计与应用

三维水平井技术有利于解决油气藏地面条件限制，提高井网部署质量，提高油气藏综合开发效率，具有明显的优势。通过对4种常见三维轨道计算模型进行分析，优选出斜面圆弧法作为三维水平井计算模型，并对三维水平井轨道形式进行优化，提出六段制水平井设计方法，以克服油藏垂深和造斜率2个不确定因素。该设计方法在JH17P25井进行了应用，完钻井深2 235 m，偏移距425 m，扭方位井段347 m，扭方位49.30°，现场施工顺利，轨迹符合率高，克服了油藏垂深的不确定性，取得了较好的应用效果，为后续三维水平井设计和施工提供了经验。

Optimization design and application of six-stage 3D horizontal well trajectory

3D horizontal well technology is obviously predominant in solving the limited surface conditions of oil and gas reservoirs, improving the quality of well pattern arrangement, and increasing the overall development efficiency of oil and gas reservoirs. In this paper, four common 3D trajectory calculation models were analyzed, and accordingly the inclined plane circular arc method was selected as the 3D horizontal well calculation model. Then, the form of 3D horizontal well trajectory was optimized and the six-stage horizontal well design method was put forward to overcome two major uncertainty factors, i.e., the vertical depth of oil reservoir and the buildup rate. This method was applied in Well JH17P25, whose total depth is 2 235 m, offset 425 m, adjusting azimuth length 347 m and offset azimuth 49.30°. Its field construction is smooth with high trajectory coincidence rate and the uncertainty of oil reservoir vertical depth is overcome. Obviously, its application effect is good. It provides the valuable experience for the subsequent design and construction of 3D horizontal wells.