River pebbles with a diameter of no more than 630 mm are sent to the NK75J jaw crusher mobile station for preliminary crushing by a forklift. After that, after careful screening by the feeder, small and medium-sized materials slide smoothly onto the main belt conveyor through the special grate hopper, merge with the materials processed by the jaw crusher, and enter the next stage of the crushing process together. After that, the NK300HS cone crusher mobile station plays a key role in the second stage of crushing with its pre-screening function. After the material is processed by the station, it will go through the pre-screening link again, and the larger particles will be automatically returned to the cone crusher for further crushing until the established particle size requirements are met. After that, the qualified aggregates will be transported to the finished product screening car for further processing. Finally, in the NK200S-3 screen washing car, these aggregates are thoroughly cleaned and screened, separated into a variety of clean finished products with different specifications, and then sent to their respective finished product piles in an orderly manner.