摘要
研究平均拉应力条件下的疲劳行为及疲劳寿命估算方法。对应力幅值进行归一化处理,推导出适用于非零平均应力的、更有普遍性的疲劳寿命计算公式;进行平均应力为0的小样疲劳试验,拟合了X65Q钢级管线管的应力-寿命曲线方程,并分析疲劳断口形貌。发现,用Gerber建立的平均应力等效公式计算出来的疲劳寿命与实际试验的疲劳寿命吻合度较高。建议用拟合的平均应力为0的应力-寿命曲线以及Gerber建立的平均应力等效公式估算平均拉应力条件下的管线管疲劳寿命。
Studied are the methods for estimating the fatigue behavior and fatigue life under the average tensile stress conditions.A more universal fatigue life formula suitable for non-zero average stress is derived by means of normalizing the stress amplitude.The S-N curve equation of X65Q linepipe is fitted via the small sample fatigue test with average stress of 0 MPa,and the fracture morphology is analyzed.As a result,it is identified that the fatigue life calculated by the average stress equivalent formula as established by the Gerber is in full agreement with the fatigue life value from the actual test.Therefore it is suggested to estimate the fatigue life of the said linepipe under the condition of average tensile stress by means of the S-N curve with the fitted average stress of 0,and the Gerber-established average stress equivalent formula.
作者
陈燕
黄兆力
刘江成
张哲平
张传友
李艳
张国柱
CHEN Yan;HUANG Zhaoli;LIU Jiangcheng;ZHANG Zheping;ZHANG Chuanyou;Li Yan;ZHANG Guozhu(Tianjin Pipe Corporation,Tianjin 300301,China;CNOOC(China),Hainan Branch,Haikou 570100,China)
出处
《钢管》
CAS
2021年第6期16-20,共5页
Steel Pipe
基金
中海石油(中国)有限公司重大攻关项目“深水钢悬链立管管材国产化研制”(编号CCL2021HNFN0027)。
