小靶前距水平井反位移轨道设计方法

The reversal displacement orbital design method of short pre-target distance horizontal well

为解决小靶前距水平井一次造斜造斜率高所造成的技术难题,采用小靶前距水平井反位移井眼轨道设计方法。使用该方法,在不移动井口位置的情况下,通过第一次反方向造斜,增大水平井的靶前距,再采用常规造斜率设计小靶前距水平井轨道,降低施工难度。主要方法是先按常规造斜率设计计算水平井所需的靶前距,此靶前距与原小靶前距的差值即为所需的反位移量,再根据反位移段的造斜率、降斜率及造斜点深度,计算出反位移井段的最大井斜角和稳斜段长度,在此基础上设计出井眼轨道的其他参数。

The reversal displacement orbital design method can solve the technical problems of high once build-up rate in pre-target distance horizontal well.In the case of unmoving the well head,through the first time reversal building angle,the pre-target distance of horizontal well was increased by this method.Then,the trajectory of short pre-target dis-tance horizontal well was designed by the general build-up rate to reduce the drilling difficulty.The main method should be divided into three parts.Firstly,the pre-target distance should be designed by the general build-up rate,and the difference between one and original short pre-target distance is the required reversal displacement.Secondly,according to the build-up rate,drop-off rate,kick off point of reversal displacement well section,the maximum deviation angle and the maintain angle section can be calculated.Finally,based on the above calculation,other parameters of well trajectory could be designed.