De-Cumulative Aggregate Weighing Concrete Batch Plant
October 14, 2021There are two styles of de-cumulating aggregate batchers. A multi compartment batcher mounted on a single scale system or individual independent batchers for each material. Unlike accumulative weighing that begins with an empty batcher, the de-cumulating batching system begins with the batcher full of material. When the material is discharged, the scale reads the weight as it decreases. Therefore, the batchers (aggregate bins) cannot be charged during the weighing process. A primary benefit of a decumulative plant is that each material can be batched at the same time, increasing speed, and facilitating the staging of materials into the truck. Utilizing feed conveyors, the loader operator charges the aggregate batcher(s) utilizing a receiving hopper and conveyor for each individual material. The material in the receiving hoppers becomes “live” storage. The front-end loader operator only needs to keep the receiving hoppers full. The receiving loader hoppers will not have discharge gates. The loader hopper’s opening onto the belt is furnished with a slide gate to adjust material flow. The feed conveyors will be designed with adequate horsepower to start the fully loaded belt. The reducers will be furnished with backstops.
The following explains operations utilizing receiving hoppers and conveyors. For batch plants with computerize automatic batching controls, an automatic conveyor start / stop “keep full” system is used.
The control completes the batching process for a material.
The control will automatically start the feed conveyor for that batcher.
The control will automatically stop the feed conveyor when a preset weight is reached.
The control will provide an internal interlock that will not allow the batcher discharge gate to open until the filling is complete.
A batcher discharge gate “closed” limit switch will not allow the feed conveyor to start during the batch cycle.