In the sand and gravel aggregate production line, the 200 tons/hour crushing system needs to take into account both capacity matching and finished product quality. In view of the needs of hard rock crushing and diversified discharging, it is recommended to adopt the combination of "jaw crusher + hammer crusher" to form an efficient and energy-saving secondary crushing process.
For primary crushing, it is recommended to use a jaw crusher. Its sturdy movable jaw plate and wedge-shaped adjustment device can handle hard materials such as granite and basalt with a compressive strength of less than 250MPa. It is recommended to choose a model with a feed size of 600×900mm or more, the maximum feed particle size is controlled within 500mm, the discharge port adjustment range is 80-180mm, and it is equipped with a 132-160kW motor. The equipment achieves stable coarse crushing through the principle of extrusion crushing, and the crushing ratio can reach 6-8. It is suitable for raw materials with high mud content. The unique toggle plate overload protection system can reduce the equipment failure rate.
For secondary crushing, a hammer crusher is recommended. The impact crushing force generated by the high-speed rotating hammer head can effectively handle medium-hard materials. It is recommended to choose a model with a rotor diameter of more than 1300mm, equipped with 4 rows and 16 groups of hammers, the maximum feed particle size is controlled within 300mm, and the finished product with less than 35mm is screened by grate bars, accounting for more than 80%. This model has a "stone-beating-iron" crushing mode, and the discharge particle size can be quickly adjusted by replacing the grate plate. When processing materials such as limestone and bluestone, the single machine capacity can reach 220-250t/h, and the pulse dust removal system can be used to achieve environmentally friendly production.
When the two machines work together, the jaw crusher completes the primary crushing and is pre-screened by the vibrating screen. The materials with a diameter of more than 80mm are returned, and the materials with a diameter of less than 80mm enter the hammer crusher for shaping and fine crushing. This configuration saves 30% of equipment investment compared to the traditional three-stage crushing, and the content of polyhedral particles in the finished product is less than 15%, which is suitable for aggregate processing in commercial mixing stations. When laying out the production line, the center distance between the two machines should be kept ≥15 meters, and a buffer silo should be equipped to ensure continuous feeding. The comprehensive power consumption can be controlled at 1.8-2.2kWh/ton.
