The stress concentration in the imbalanced section of plastically imbalanced casing resulted from uniform load can easily make the casing bending,deforming or breaking out.

• 套管受到非均匀载荷的作用易产生塑性变形,在应力集中区,易造成套管弯曲、变形或错断,用金属磁记忆技术可有效判断套管应力集中区域。