B型套筒结构尺寸优化设计研究OA

A pipeline defect model and a B-type sleeve welding model were established to address issues such as unreasonable sleeve geometric dimensions,excessive design wall thickness,and cracking of fillet welds caused by the use of B-type sleeves.The distribution patterns of equivalent stress and residual stress in B-type sleeve repair welding for defects of different sizes were studied,and recommendations for key parameters of B-type sleeve design geometric dimensions were provided.Results indicate that the length,width,and depth of pipeline defects only affect the magnitude of defect stress and have little effect on the range of stress concentration.However,the size of the defect distance from the end of the sleeve provided in the standard is too small and does not consider the impact of defects on equivalent stress.The welding residual stress of B-type sleeve fillet weld will increase with the increase of sleeve length and sleeve thickness.As the sleeve wall thickness increases,the welding residual stress at the fillet weld gradually increases,but the maximum equivalent stress on the outer surface of the pipeline first decreases and then increases.The sleeve wall thickness should be controlled between 1 and 1.4 times the pipeline wall thickness.