输气管道运行压力循环特征的雨流计数分析  

Rain Flow Counting Analysis on Operating Pressure Cycle Characteristics of Gas Pipeline

作　　者：帅健[1] 张怡[1] Shuai Jian;Zhang Yi(College of Safety and Ocean Engineering,China University of Petroleum(Beijing))

机构地区：[1]中国石油大学(北京)安全与海洋工程学院

出　　处：《石油机械》2022年第3期115-122,共8页China Petroleum Machinery

基　　金：国家自然科学基金项目“基于应变的管道环焊缝断裂评估方法研究”(51874324)。

摘　　要：对管道运行压力的循环特征进行分析是预测管道疲劳寿命的重要研究基础。鉴于此,基于雨流计数法统计了随机载荷谱中的压力循环,对某管道两个站点出站压力的变化历程进行统计,分析了站点内管道压力循环的幅值、均值、频次占比与损伤占比等。分析结果表明:输气管道压力比大于0.8的压力循环次数均占总循环的90%以上;采集周期对大幅压力循环的计数影响较小,对小幅压力循环计数影响较大;管道压力循环以不损失大幅循环为原则选择采集周期;大幅循环的频次占比越高,对管道造成的损伤占比也就越大,但当循环次数较多且循环幅值较小时,大量小幅循环是造成管道损伤的主要原因。所得结论可为油气管道的疲劳寿命预测提供理论支撑。The analysis on the operating pressure cycle characteristics of gas pipeline is an important research basis for predicting the fatigue life of the pipeline.Based on the rain flow counting method,the pressure cycle in the random load spectrum was counted,the outlet pressure change history of two stations in a pipeline was counted,and the pressure cycle amplitude,mean value,frequency proportion and damage proportion of the pipeline in the stations were analyzed.The analysis results show that the number of pressure cycles with pressure ratio greater than 0.8 in the gas pipeline accounts for more than 90%of the total cycles;the acquisition cycle has little effect on the counting of large pressure cycles,but has great effect on the counting of small pressure cycles;the acquisition cycle is selected for pipeline pressure cycle based on the principle of no loss of large cycle;the higher the frequency proportion of large cycle,the greater the proportion of damage to the pipeline is,but when the number of cycles is large and the cycle amplitude is small,a large number of small cycles are the main causes of pipeline damage.The analysis conclusions provide a theoretical support for the fatigue life prediction of oil and gas pipelines.

关 键 词：输气管道 压力循环 雨流计数 载荷谱 疲劳损伤 

分 类 号：TE973[石油与天然气工程—石油机械设备]