Effect of the gas–solid two-phase flow velocity on elbow erosion

• A new method to predict particle erosion was proposed considering effects of gas pressure, gas velocity and solid velocity.
• Results calculated by the method were verified by comparing with an inspection report and test results.
• The results of the proposed method were compared with those of API-14E and Salama's methods.
• Effects of different gas and particle velocities on particle erosion under high and low pressure were compared.

Because of the rapid development of oil and gas pipelines and the increasing number of pipeline accidents, pipeline safety has garnered more attention around the world. Erosion on the inner diameter of pipes is one of the main factors in pipeline failure. Since experimental methods for wall thickness inspection of pipelines are expensive, an accurate model for predicting erosion rate of pipelines under working conditions is needed. A new erosion prediction model is proposed in this research which combines the theoretical and Lagrange discrete phase models for erosion. The model considers effects of gas–solid multiphase velocity and gas pressure. It is applied to elbows under the working conditions of a gas station of the Daqing Oil and Gas Company in China. The results are considerably closer to measured erosion of elbows than the results calculated using existing models. The comparison between erosion under high and low gas pressures shows that the effect of gas-phase velocity on erosion rate is more significant in elbows under high-pressure conditions.