水平井油管柱射孔振动的有限元分析

FINITE-ELEMENT ANALYSIS OF TUBE STRING VIBRATION ON HORIZONTAL WELL

练章华 林铁军 刘健 乐彬 陈举芬 徐月霞 杨涛

Lian Zhanghua Lin Tiejun Liu Jian Le Bin Chen Jufen Xu Yuexia Yang Tao

西南石油学院, 四川 成都 610500 CNPC东方地球物理公司, 新疆 库尔勒 841001 西南油田公司, 四川 广汉 618300

射孔时产生的高压气体会使油管柱产生振动,使管柱受力处于恶劣状态。对于水平井,因管柱较长,用解析方法求解其动力学过程非常困难,因此,根据井眼轨迹参数数据,建立了水平井油管柱射孔振动的有限元模型,在水平井造斜段采用了变坐标系统,使油管柱沿轴向方向有位移,在径向受井筒约束。射孔时的冲击波载荷施加于水平井射孔段部位的油管柱纵向方向。以此为基础详细分析了射孔时油管柱的纵向振动位移和速度随时间的变化关系,结果表明,射孔时对油管柱产生纵向振动载荷远高于对油管柱产生的横向载荷,即纵向(轴向)振动起主要作用。同时,分析了油管内等效应力随时间的变化关系,并得出:在射孔后1.0~1.5 s时间范围内,油管柱内将会出现最大等效应力峰值,此应力发生在造斜段,其最大应力峰值载荷的确定为合理设计油管柱和选择减震器个数提供了理论数据。

The finite model of tube string vibration on horizontal well was established according to the data of wellbore trajectory,and adopted variable coordinate system to make the tube string displacement along axial orientation and restriction along radial orientation.The tube string of perforated section on horizontal well was vertically loaded by shock wave while it was perforated.The variety relation with time during perforation between axial direction vibration displacement of tube string and velocity was analyzed in detail and obtained that the vertical vibration load of tube string generated by perforation was much more than radial,that was the axial direction vibration took mostly effect.Meanwhile,the variety relation between equivalent stress of tube and time was analyzed and had a conclusion that during the time about 1.0 to 1.5 seconds after perforation the peak equivalent stress value of tube string was generated and sat in deflecting section.It provided the theory data for reasonable designing tube string and how many vibration absorbers were selected.

10.3969/j.issn.1000-7393.2006.01.015