Abstract A resonant test rig aimed at fatigue tests on tubular elements is presented in this paper, showing the working principle and control strategy. Corroded drill pipe connections and pipe bodies with different sizes and different steel grades were tested. A relatively high stress amplitude was applied to all the specimens. The fatigue initiation was observed in the central region of the pipe specimens, where the stress amplitude is highest, and away from the tool joints of the connection specimens, mainly because of the different outer diameters. The fatigue crack was initiated at the pitting corrosion sites, which limited the potential fatigue strength of the drill pipes. Small-scale tests were also performed, showing a much higher base material strength. A comparison analysis was thus used to evaluate the fatigue size and surface condition effects, and to estimate the maximum fatigue stress concentration factors at the connections.

中文翻译：

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S140 和 S150 级腐蚀钻杆接头和管体的疲劳共振试验

摘要 本文提出了一种针对管状元件疲劳试验的共振试验台，展示了其工作原理和控制策略。对不同尺寸和不同钢种的腐蚀钻杆接头和管体进行了测试。对所有试样施加了相对较高的应力幅值。疲劳起始出现在管道试样的中心区域，应力幅最大，远离连接试样的工具接头，主要是由于外径不同。疲劳裂纹起源于点蚀部位，限制了钻杆的潜在疲劳强度。还进行了小规模测试，显示出更高的基材强度。