含沟槽缺陷铜镍合金管爆裂压力计算

Burst pressure calculation of Cu-Ni alloy pipeline with groove defect

摘要:

为了准确评价铜镍合金管存在沟槽缺陷时的爆裂压力,建立了爆裂压力预测公式,进行了爆裂过程的数值模拟,确定了修正函数,进行了静水压爆破试验。数值模拟与试验结果均表明:DNV标准与数值模拟结果误差随腐蚀深度增加先减小后增大,依靠含缺陷深度参数的修正函数建立的预测公式可以有效预测铜镍合金管爆裂压力,试验证明公式准确性较高；对比爆破试验裂口形貌,管道在仅受内压状况下爆裂过程的数值模拟效果较好；管道在剩余壁厚较薄时表现为塑性断裂,剩余壁厚较厚时表现为脆性断裂。爆裂压力的研究可为科学维修舰船管路提供理论依据,对指导管路状态评估有重要意义。

Abstract:

In order to accurately evaluate the bursting pressure of Cu-Ni alloy tube with groove defect, the prediction model of burst pressure was established and the bursting process was simulated, the correction function was determined by the least square method, and the hydrostatic blasting test was carried out. Both the numerical simulation and test results show that the error between DNV standard and numerical simulation results decreases first then increases with the increase of corrosion depth. The prediction formula established by the correction function containing defect depth parameter can effectively predict the burst pressure of the Cu-Ni alloy pipe, and the test proves that the formula has a high accuracy. Compared with the crack morphology of blasting test, the numerical simulation of pipe bursting process under the condition of only internal pressure is better. The ductile fracture occurs when the residual wall thickness is thin, while the brittle fracture occurs when thick. The study of burst pressure can provide theoretical basis for scientific maintenance of ship pipeline and has great significance to guide pipeline condition assessment.