1. Before loading, one feed port is opened and the other feed port is closed;
2. Close the unloading disc valve and the external air source interface;
3. Open the exhaust valve;
4. Choose one of the bins to load, and after loading one bin, close the inlet of the bin;
5. Open the feed port of another warehouse and load it;
6. After the filling of the two warehouses is completed, close the exhaust valve and the feeding port;
7. Tighten the feed port.