Mobile trommel washer is a kind of equipment used to wash ores in industries such as ferrous metal, nonferrous metal, metallurgy and mining. The washing process is: Add clear water to such equipment and remove impurities such as mud and sand of the raw core dissolved in water. After such washing process, the ores can meet technological requirements. Drum sand and gravel washers are suitable to wash ores with the size of below 80mm. Take manganese ore for example, if the silt content of manganese ore is 80%, this figure can become smaller than 15% after they are washed by sand and gravel washer so that the ores can meet technological requirements and hit the economic target.