钻杆接头缺陷影响使用寿命的试验研究

针对钻杆接头反台肩处存在的外加厚过渡不全及几何缺陷 ,在静态纯弯曲条件下 ,用电阻应变片测试了所引起的应力集中系数 .通过弯曲疲劳试验对钻杆使用寿命的影响规律进行了试验研究 .结果表明 ,这种缺陷对钻杆寿命影响很大 ,在台肩深度相同时 ,缺陷半径越小 ,钻杆寿命越短 .对钻杆接头缺陷的检验标准与钻杆的分级管理提出了合理建议 .

Effect of the Defect of Drill Pipe Joint on the Service Life of Drill Pipe

There are geometric defects at the shoulder of drill pipe joint. Their effect on the service life of drill pipe was studied. The stress concentration factor caused by the defects was measured by electric resistance strain foils under static complete bending. And the effect law on the service life was obtained by bending fatigue test. The result of the test shows that the effect is serious, and when the depth of the shoulder is definite, the smaller are the radii of the defects, the shorter is the service life.Some suggests are put forward on the check standard of the defect and the graded management of drillpipe.