耦合振动对钻柱疲劳的影响

INFLUENCE OF COUPLING VIBRATIONS ON DRILLING STRING FATIGUE

从钻柱在耦合振动时各截面的应力变化规律出发，运用金属非比例循环概念及特性，讨论了双轴非比例循环对钻柱疲劳的影响．结果表明，金属耦合振动引起双轴非比例循环的应力明显高于单轴振动及比例循环的应力；振幅是影响非比例循环损伤的重要因素之一。

The concept of non-proportional cycling is introduced and applied to inspect the fatigue characteristic of drilling string when longitudinal and torsional vibrations occur simultaneously. The study shows that the non-proportional and double-longitudinal cycling stress resulted from the metal cupping vibration is higher than that of single-longitudinal and proportional cycling- The amplitude is an important factor for resulting in fatigue wear of drilling string.