CAJ | 학술논문

针对钻井过程中钻柱工作载荷或钻压超过某一临界值导致钻柱失稳现象,建立了钻柱非线性稳定性问题的分析模型,用数值分析的方法对整个钻柱系统的非线性屈曲过程进行了有限元仿真分析,解释了钻柱的失稳机理以及钻柱自重、钻压、转速、扭矩和井斜角等因素对钻柱屈曲的影响规律,研究了钻柱在井筒中发生屈曲时的位移、受力状况和各种工况下的失稳临界载荷.结果表明,在相同条件下钻柱螺旋屈曲临界载荷随井斜角增大而增大,呈非线性变化;临界载荷随扭矩的增大而减小,井斜角较大时临界载荷减小的幅度较小.对钻柱在井筒中的非线性屈曲行为研究和钻具组合设计的优化具有一定的参考价值.
침대찬정과정중찬주공작재하혹찬압초과모일림계치도치찬주실은현상,건립료찬주비선성은정성문제적분석모형,용수치분석적방법대정개찬주계통적비선성굴곡과정진행료유한원방진분석,해석료찬주적실은궤리이급찬주자중、찬압、전속、뉴구화정사각등인소대찬주굴곡적영향규률,연구료찬주재정통중발생굴곡시적위이、수력상황화각충공황하적실은림계재하.결과표명,재상동조건하찬주라선굴곡림계재하수정사각증대이증대,정비선성변화;림계재하수뉴구적증대이감소,정사각교대시림계재하감소적폭도교소.대찬주재정통중적비선성굴곡행위연구화찬구조합설계적우화구유일정적삼고개치.
Aiming at the instability phenomena of drill string in the process of drilling operation,the nonlinear drill string helical bucking model is set up.Also,the finite element analysis is presented with numerical method.The theory and the rule of drill string bucking influenced by dead load,rotating speed,weight on the bit and the well deviation are explained.It is shown that under the same conditions,the helical buckling load increases nonlinearly with the increase of the well deviation and decreases nonlinearly with the increase of torsion and the reduction decreases with the increase of deviation angle.From the analysis,the displacement and stress are objectively reflected when drill string buckling occurs in the well.The critical buckling load of drill string under various conditions is forecasted.For the study on nonlinear buckling of drill string,the optimization of BHA design and the reduction of drilling cost,there are both the theoretical and project practical significance.