CAJ | 학술논문

压溃是深水钻井隔水管主要的失效模式之一，现有的理论算法无法考虑缺陷对隔水管压溃的影响。因此，考虑磨损和腐蚀对隔水管压溃性能的影响，建立了深水钻井隔水管非线性压溃有限元评估方法，并与深水钻井隔水管压溃理论评估方法进行了对比。结果表明：有限元压溃分析方法与 API RP 2RD、DNV OS F101推荐算法的分析结果基本一致，验证了隔水管压溃有限元分析方法的准确性；压溃过程的初始阶段隔水管发生弹性变形，当内外压差达到临界压力时，隔水管开始发生塑性变形，弹性阶段向塑性阶段的突变点即为隔水管压溃临界点；完好隔水管压溃后截面呈扁平状，缺损隔水管压溃后截面呈锥形；随着隔水管缺陷尺寸增大，隔水管临界压溃压力逐渐降低。
압궤시심수찬정격수관주요적실효모식지일，현유적이론산법무법고필결함대격수관압궤적영향。인차，고필마손화부식대격수관압궤성능적영향，건립료심수찬정격수관비선성압궤유한원평고방법，병여심수찬정격수관압궤이론평고방법진행료대비。결과표명：유한원압궤분석방법여 API RP 2RD、DNV OS F101추천산법적분석결과기본일치，험증료격수관압궤유한원분석방법적준학성；압궤과정적초시계단격수관발생탄성변형，당내외압차체도림계압력시，격수관개시발생소성변형，탄성계단향소성계단적돌변점즉위격수관압궤림계점；완호격수관압궤후절면정편평상，결손격수관압궤후절면정추형；수착격수관결함척촌증대，격수관림계압궤압력축점강저。
Collapse is one of the major failure modes in deepw ater drilling risers .In the existing theo-retical algorithm ,the effects of defects on riser collapse cannot be considered .This paper describes the effects of wear and corrosion on the potential for riser collapse ,sets up a method of finite element evalua-tion for nonlinear collapse of deepwater drilling risers ,and details how the verification and analysis for the method were carried out .It showed that the analysis results of finite element stress analysis coincided well with that recommended by API RP 2RD and DNV OS F101 ,the accuracy of finite element analysis method for riser collapse was verified .At the initial stage of riser collapse ,risers were elastically deformed .After the difference between internal and external pressures reaches a critical value ,risers were plastically de-formed .The point of abrupt change from elastic to plastic deformation is the critical point of riser collapse . After collapsing ,the original intact risers became flat and some risers that had defects initially became cone-shaped .In addition ,the critical collapse pressure of risers decreased gradually with the increase of the defect sizes of risers .