Heat source: If the heat source is different when drying sand, the temperature inside the furnace is different, resulting in a varied-temperature airflow in the dryers. If the temperature is too low, the drying time will be long, and the output of the equipment will also be affected. Rotation speed of barrel: In general, the rotation speed of the barrel determines the drying time of the product. The faster the rotation speed is, the faster the materials move inside, and discharged from the barrel. Evaporation intensity of materials: Different materials have different evaporation intensity, which will affect the drying efficiency. The more evaporation intensity of material has, the more efficiently the dryers are. Degree of moisture: Generally, the fluid material is inadvisable to conveying into the dryer equipment, or it will cause the waste of heat resources.