Erosion-corrosion Behavior Of X65 Pipeline Steel In Simulated Formation Water

In the process of oil and gas exploitation and transportation,the seabed oil and gas pipelines have long suffered the impact of the erosion-corrosion of the transmission medium.As is known to all,the contact environment of underwater structural components is a multiphase flow medium containing oil and gas.The influence parameters include CO₂ content,type and content of solid particles,flow rate and temperature.At the same time,commonly used for subsea oil and gas pipelines,such as the elbow,three links,reducer,corrosion condition of different types are not the same.So the research of deepwater oil and gas transportation structure in oil and gas transmission medium erosion corrosion behavior and failure mechanism for prolonging the service life of the structure under water,prevent leakage accidents and fracture of underwater structures has an important guiding role.In order to clearly understand the corrosion behavior of submarine oil and gas pipeline,this paper takes the X65 pipeline steel as the experimental material,and mainly studies the following two aspects:?1?Firstly,the erosion and corrosion rules of X65 pipeline steel were studied by various factors such as flow rate,fluid temperature,sediment concentration and impact angle.Then the main factors of these factors were found by orthogonal experiment and variance analysis.Finally,combined with the experimental data,verify the numerical simulation of the calculation results.The temperature is the main controlling factor,and the sand concentration ranks second.From qualitative and quantitative point of view,the results of numerical simulation are consistent with the experimental results.?2?In order to study the fluid trajectory distribution and corrosion rate of the three-way pipe fittings,the most important parts of the three-way pipe used in the process of submarine oil and gas transportation are studied by using the combination of experiment and numerical simulation.?1?The erosion-corrosion rate at the bottom of the pipe is larger than that at the top of the pipe;?2?No matter whether the bottom of the pipe or the top,the erosion-corrosion rate before the split is greater than the erosion-corrosion after the split;?3?The maximum erosion-corrosion position is at the bottom of the pipe before the shunt.The results of numerical simulation are in agreement with the experimental results.