钻具组合对扩眼器振动的影响

已有研究表明扩眼器的横向振动是引起扩眼钻具失效的主要原因,而合理的扩眼器与领眼钻头的钻压分配与井下钻具组合则可以改善扩眼器的横向振动。以前在计算钻头与扩眼器的钻压比时常采用几何面积法,但这种方法影响因素单一。在PDC单齿受力模型的基础上,通过求出每个齿的受力,进而求出领眼钻头和扩眼器所受的钻压,再求得钻压比; 通过有限元仿真,分析了钻具组合对扩眼器振动的影响。结果表明:领扩眼钻具间的距离对扩眼器的振动有一定的影响,适当的距离可以有效降低扩眼器钻进时振动强度; 在本文工况下,领扩眼钻具间钻铤数量为2根时振动最小; 稳定器数量的增加可以减缓扩眼器的振动强度。研究结果可为随钻扩眼作业的提速提效给予技术支持。

Influence of BHA on Vibration of Reamer

According to the existing study results, the lateral vibration of the reamer is the main reason for the failure of the reamer, and the reasonable WOB distribution between the reamer and the pilot bit, and the BHA can improve the lateral vibration of the reamer. The geometric area method was often used geometric area method to calculate the WOB ratio between the drill bit and the reamer, but this method has a single influence factor. Based on the PDC single-tooth force model, the weight on the pilot bit and the reamer by calculating the force on each tooth, and the weight-on-bit ratio were obtained. Through finite element simulation, the influence of the drill tool assembly on the vibration of the reamer was analyzed. The results show that the distance between the collar reaming tools has a certain effect on the vibration of the reamer, and a proper distance can effectively reduce the vibration intensity of the reamer during drilling. When the number of collars is two, the vibration is the smallest; the increase in the number of stabilizers can slow down the lateral and longitudinal vibration of the reamer. The research results can provide effective technical support for improving the speed and efficiency of reaming while drilling.