Steel-lined Plastic PipeInternal pitting requires not only high-intensity impact from coarse abrasive particles but also the use of fine abrasive particles to remove erosion products for effective cleaning. A reasonable blending design not only reduces the wear on the PTFE-lined pipes and nozzles (blades) caused by abrasives but also significantly improves the utilization rate of the abrasive material in the steel-lined machine. Typically, the particle size of steel shot ranges from 0.8 to 1.3 mm, while steel grit ranges from 0.4 to 1.0 mm, with 0.5 to 1.0 mm being the main component. The ratio of sand to shot is generally 5 to 8. It should be noted that in practice, achieving the ideal ratio of steel grit to steel shot in the abrasive mixture is challenging due to the higher breakage rate of the hard and brittle steel grit compared to steel shot. Therefore, during operation, continuous sampling and testing of the mixed abrasive should be conducted, and new abrasive should be added to the descaling machine based on the particle size distribution. Moreover, the number of steel grits should be predominant in the new abrasive added.