Safety assessment of large-scale tanks

The safety assessment of large-scale tanks containing defects is quite important for production. The failure assessment curve (FAC) of SPV490Q steel used for 100000m(3) large-scale tanks was built based on engineering assessment method, which provides technical support for assessment of pressure vessels containing defects made of SPV490Q steel. The critical crack sizes for 100000m(3) large-scale tanks made of SPV490Q steel were obtained through stress analysis and defect assessment. The critical crack sizes were 9.44mm in toe of large fillet weld of tank and 8.84mm in the joint between bottom plate and inner annular plate. The results offer reference for the inspection in service and defect assessment of large-scale tanks.