The gas shielded screen is aimed at some materials that cannot be in contact with air during the screening process, otherwise oxidation or explosion will occur. Therefore, in the screening process, the sieve machine, silo, and receiving hopper are completely sealed, and at the same time, they need to be filled with inert gas protection. Before screening, the gas is replaced in the sieve machine, receiving bin and pipeline, and the oxygen content is lower than the set value, and the feeding production can be carried out. Start the rotary vibrating screen, turn on the ultrasonic power supply at the same time, open the opening valve, and put the material into the ultrasonic vibrating screen at a constant speed for fine screening.