Erosion prediction model for super 13Cr tubing during large-scale hydraulic fracturing

Sand-carrying fracturing fluid flowing at high-speed during large-scale hydraulic fracturing can erode inner walls of tubing, resulting in thinning of tubing sidewall and reduction of tubing loading capacity. To predict erosion rate of tubing during large-scale hydraulic fracturing accurately, the impacts of erosion angle and fluid flow speed on erosion rate of the super 13Cr tubing have been tested with an erosion testing unit made by ourselves, solid-liquid dual-phase fluid made of 0.2 % guar fracturing fluid and quartz sand of 40/70 meshes, and an erosion prediction model for fracturing with large discharging rate and high sand proportion has been constructed. By using the newly constructed model, impact of total fluid volume and discharging rate on wall thickness loss of the super 13Cr tubing can be predicted accurately. Case study results show the super 13Cr tubing may lose sidewall thicknesses of 0.2-1.3 mm during large-scale fracturing. Therefore, cares shall be taken to control discharging rate and sand content properly to maintain necessary safety performance of tubing sidewalls in case of erosion.