针对非均匀载荷下套管磨损后抗挤强度降低的问题,将磨损简化为套管的壁厚不均度和内壁不圆度几何缺陷。在此基础上,建立了非均匀载荷下磨损套管抗挤强度计算方程。该方程计算值与试验值的对比表明,该方程计算结果是可靠的,可为复杂地层磨损套管柱设计提供理论依据。研究表明,当载荷不均匀程度较小时,磨损对套管抗挤强度的影响较大;当载荷不均匀程度较大时,磨损对套管抗挤强度的影响较小。
Non-uniform loading can reduce the collapse resistance of worn casings.For the purpose of finding an algorithm to compute it, worn casings are looked at as geometry imperfections such as ovality and eccentricity. Hence new equations for computing the collapse resistance of crescent-shaped worn casings under non-uniform loading are established. The comparison of different equations with experimental data that the new equations are more reliable and provides theoretical basis for the design of casings in ultra-deep wells. The research indicates that wear has much key factor for its reduction when the non-uniform loading smaller effects on the collapse resistance. larger effects on the collapse resistance and is a coefficient is smaller and that wear has much smaller effects on the collapse resistance.