依照英国BS7448和挪威船级社DNV-OS-F101标准对管壁厚18.0 mm的X70级气体保护焊环焊管热影响区进行断裂韧度CTOD(crack tip opening displacement)试验,并应用数理统计方法对试验结果进行了分布拟合检验.文中分别采用了柯尔莫哥洛夫检...依照英国BS7448和挪威船级社DNV-OS-F101标准对管壁厚18.0 mm的X70级气体保护焊环焊管热影响区进行断裂韧度CTOD(crack tip opening displacement)试验,并应用数理统计方法对试验结果进行了分布拟合检验.文中分别采用了柯尔莫哥洛夫检验法和A2-W2检验法对试验结果进行了拟合检验和对比分析,得到了该X70钢焊接接头热影响区CTOD分布规律.结果表明,应用A2-W2检验法进行拟合检验的敏感度较高,且断裂韧度数据拟合较好的统计分布函数为Weibull分布函数,可结合欧洲工业完整性评定程序(SINTAP)的可靠性评定方法,计算得X70钢焊接接头热影响区CTOD断裂韧度概率密度分布函数.展开更多
The recently developed European flaw assessment procedure, structural integrity assessment procedure（SiNTAP） is applied to assessment for welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw ...The recently developed European flaw assessment procedure, structural integrity assessment procedure（SiNTAP） is applied to assessment for welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw and surface flaw at the weld toe. As one of the basic input data, fracture toughness crack tip opening displacement （CTOD） tests are conducted at 0℃ and performed according to the requirements of the standard of BS7448. For the heat affected zone （HAZ） specimens, the microstructure observation is performed to insure that the tip of the crack is located in the coarse grain zone. The result explains the dispersity of the test values. In structural integrity assessment procedure-fracture assessment diagram（SINTAP FAD） method, the failure curves of welded joints at level 1 and 3 are derived from the tensile test results. The results of the assessment show that all assessment points are located within the failure lines of analysis level 1 and 3. So the welded joint of the pipeline is safe. This study laid the foundation of application of SINTAP to pipeline structure assessment.展开更多
The European Structural Integrity Assessment Procedure（SINTAP） was applied to the assessment of welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw and surface flaw at the weld toe. At defau...The European Structural Integrity Assessment Procedure（SINTAP） was applied to the assessment of welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw and surface flaw at the weld toe. At default level（ level 0）, the assessment point was established by esti- mating fracture toughness value K1c conservatively from Charpy energy test data. At the same time, the analysis level 1 （basic level）was applied based on the fracture toughness CTOD. Then the two assessment levels were compared. The assessment results show that all assessment points are located within the failure lines of analysis levels 0 and 1. So the welded joint of the pipeline is safe. It can be concluded that the assessment based on Charpy absorbed energy is practicable when other fracture toughness data are not available, or cannot be easily obtained. The results are conservative.展开更多
文摘依照英国BS7448和挪威船级社DNV-OS-F101标准对管壁厚18.0 mm的X70级气体保护焊环焊管热影响区进行断裂韧度CTOD(crack tip opening displacement)试验,并应用数理统计方法对试验结果进行了分布拟合检验.文中分别采用了柯尔莫哥洛夫检验法和A2-W2检验法对试验结果进行了拟合检验和对比分析,得到了该X70钢焊接接头热影响区CTOD分布规律.结果表明,应用A2-W2检验法进行拟合检验的敏感度较高,且断裂韧度数据拟合较好的统计分布函数为Weibull分布函数,可结合欧洲工业完整性评定程序(SINTAP)的可靠性评定方法,计算得X70钢焊接接头热影响区CTOD断裂韧度概率密度分布函数.
基金This project is supported by National Natural Science Foundation of China(No.50375109).
文摘The recently developed European flaw assessment procedure, structural integrity assessment procedure（SiNTAP） is applied to assessment for welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw and surface flaw at the weld toe. As one of the basic input data, fracture toughness crack tip opening displacement （CTOD） tests are conducted at 0℃ and performed according to the requirements of the standard of BS7448. For the heat affected zone （HAZ） specimens, the microstructure observation is performed to insure that the tip of the crack is located in the coarse grain zone. The result explains the dispersity of the test values. In structural integrity assessment procedure-fracture assessment diagram（SINTAP FAD） method, the failure curves of welded joints at level 1 and 3 are derived from the tensile test results. The results of the assessment show that all assessment points are located within the failure lines of analysis level 1 and 3. So the welded joint of the pipeline is safe. This study laid the foundation of application of SINTAP to pipeline structure assessment.
基金Supported by National Natural Science Foundation of China(No. 50375109)
文摘The European Structural Integrity Assessment Procedure（SINTAP） was applied to the assessment of welded joints of the API 5L X65 pipeline steel with an assumed embedded flaw and surface flaw at the weld toe. At default level（ level 0）, the assessment point was established by esti- mating fracture toughness value K1c conservatively from Charpy energy test data. At the same time, the analysis level 1 （basic level）was applied based on the fracture toughness CTOD. Then the two assessment levels were compared. The assessment results show that all assessment points are located within the failure lines of analysis levels 0 and 1. So the welded joint of the pipeline is safe. It can be concluded that the assessment based on Charpy absorbed energy is practicable when other fracture toughness data are not available, or cannot be easily obtained. The results are conservative.
