Erosion damage mechanism of buckled tubing in high pressure and high production gas wells

The high-speed gas flow in tubing causes erosion damage to the string for high pressure and high production gas wells, and the erosion threats the security of gas production and operation seriously. The tubing string with packers tends to be buckled, making the erosion more damaging, which is prone to cause downhole string failure or even well field accidents. Therefore, considering the flow channel features in the tubing string of sine buckling and helical buckling, based on the theory of the natural gas flowing dynamics, the CFD model and sand erosion model were established for a high pressure and high production gas well in Kela 2 gas field. Numerical simulation was conducted on the flow performance of natural gas in sine and helical buckled tubing string, and the erosion velocity and shear stress of sand flowing in the tubing was studied. The force and erosion law of natural gas to buckled tubing were obtained. It provided a reference for real-time prediction of erosion damage in high pressure and high production gas wells, and a theoretical basis for the proposal of erosion damage prevention measures.