Pipeline buckling is one of the failure modes of oil and gas pipelines, including local buckling and global buckling.The buckling and deformation of buried pipelines are complicated. The factors include the internal and external pressures, bending moment, axial force and so on.The pipeline is affected by its structural characteristics, and is prone to buckling when the stress and deformation conditions are slightly worse than its design tolerance. A comprehensive analysis and study of a local buckling failure of a refined oil pipeline was conducted. This was carried out by tensile testing, Charpy impact and pipe fracture mechanical tests to get the parameters of the conventional mechanical properties of the pipe. A finite element simulation method was used and a buckling pipe model was established to analyze the stress and deformation of the pipeline under different loads and influencing factors. The results show that under some conditions, the impact of the material tends to increase with an increase of the test temperature. The local buckling failure of a pipeline is caused by the combined effect of axial stress, bending moment and internal pressure. The axial load is mainly caused by the instability of pipeline buckling to reduce the internal pressure. Increasing the wall thickness can enhance the ability to resist deformation. The corresponding measures and suggestions for pipeline maintenance are put forward to reduce the risk to pipeline operation.
Key words：
product pipelines ; buckling deformation ; axial load ; finite element analysis ; material test ; landslide
