冷热交替输送管道适用性评价

Fitness for Service Assessmenton a Pipeline for Cold-hot Oil Alternating Transportation

通过对某管道钢管进行壁厚检测、无损检测、钢管材料适用性评价、含缺陷管道剩余强度评价和疲劳寿命预测等工作,评价了该管道冷热交替输送钢管材料的适用性和安全性,为管道检测、维修、更换周期的确定提供技术依据。评价结果表明:该管道在材质上满足相关标准要求;检测发现的裂纹型缺陷,在运行压力6.27 MPa,输送温度在20℃~60℃范围内变化时均可接受;疲劳裂纹扩展评估和寿命预测结果表明,取样管段检测到的最大缺陷在交变载荷作用下会发生扩展,管道剩余循环周次为3691次,按波动频率70次/年计算,管道剩余寿命为52年,取疲劳安全系数为6,则建议管道的检测周期不超过8年。

Fitness for service and safety assessment on a pipeline for cold-hot oil alternating transportation were carried out through wall thickness inspection, nondestructive detection, fitness for service assessment of steel pipe material, remaining strength evaluation and fatigue life prediction, which can provide technical support for making decision for inspection and maintenance of the pipelines. The assessment re- suits indicate that the material of pipeline can meet the requirement of the standard, and the detected crack defects are acceptable ureter the pressure of 6.27 MPa and the temperature ranges at 20~C to 60~C, and the detected maximum crack will propagate under alternating loads and the safety operating circle of the pipeline is 3 691. According to the fluctuation frequency 70 times/year, the fatigue life is 52 years under the safety factor of 6, the recommend detection period of the pipeline is not more than eight years.