含错边缺陷悬空管道的安全研究

Security Research of Pipeline with Unfitness Defect in Suspended State

以涩宁兰一线管道为工程背景,根据GB50236-2011《现场设备、工业管道焊接工程施工规范》确定不同壁厚下标准允许的错边量。基于应变失效判据,建立了输气管道在不同地区的失效判别标准,以错边量、错边缺陷在管道悬空段位置为变量,研究管道上的受力特点及不同变量对悬空管道失效悬空长度的影响,结果表明错边量的大小对管道的失效影响很大,当错边量Δ≥2 mm时,管道的安全悬空长度和极限悬空长度急剧减小,管道极易发生失效。

Taking a segment of Se-ning-lan first line's gas pipeline as the engineering background,according to GB50236-2011 《Code for construction of field equipment,industrial pipe welding engineering》,the size of unfitness of butt joint in the different wall thicknesses was determined. Based on strain failure criterion,gas pipeline failure criterion in different regions was established. Pipeline mechanical characteristics and different variables' influence on dangling length of suspended pipeline failure were discussed with unfitness of butt joint and unfitness defect in pipe dangling position as variables. Results show that the size of unfitness of butt joint has great influence on pipeline failure. After unfitness of butt joint Δ is more than 2 mm,the safety and limit suspended length decreases sharply,and pipeline is prone to fail.