基于ANSYS软件的钻柱横向振动分析

Lateral Vibration Analyses of Drilling String with ANSYS Software

采用ANSYS分析软件对2000m以内钻柱在垂直孔、不考虑接头影响和忽略钻头几何尺寸条件下的整体横向振动进行分析,得到钻铤长度、钻柱长度对固有频率的影响及具有意义的一些认识,同时获得钻柱横向振动的1、2、3、4、5阶固有振型。结果表明:钻柱的横向振动低阶固有频率随钻铤长度的增加而增加,而高阶固有频率随着钻铤长度的增加很快又降低;固有频率随着钻柱长度的增加而减小。为实际钻进工程提供理论依据。

The lateral vibration of the drilling string are analyzed by using software ANSYS, under following conditions-within 2000m straight borehole,ignoring the effects of tool joint, size of drill bits. The relationship between the inherent frequency of drilling string and length of drill collars, length of drill pipes are gained. Meanwhile one to five step inherent frequency of drilling string lateral vibration are gained. Results indicate that the lowlevel inherent frequency increases with a rise in the length of the drill collar, while the high-level inherent frequency soon decreases, and the inherent frequency reduces with a rise in the length of the drilling string. The results provides a theoretical basis for the actual drilling projects.