Fan shell with good dustproof effect

The utility model relates to the technical field of fans, in particular to a fan casing with a good dustproof effect, which comprises a mounting frame body and two semicircular casings forming a circular cavity, and the semicircular casings are symmetrically arranged, detachably connected with the mounting frame body and suitable for adjusting the semicircular casings to move eccentrically in thereverse direction. The mounting frame body comprises a mounting plate, four U-shaped plates and L-shaped connecting plates connected to the two ends of the mounting plate. The U-shaped plates are arranged in a rectangular array mode and connected with the back face of the installation plate, kidney-shaped holes located in the installation plate are formed over the U-shaped plates, the U-shaped plates are suitable for forming T-shaped grooves, and the T-shaped grooves are connected with the semicircular shells through T-shaped bolt assemblies. By means of the mode, the draught fan shell with the good dustproof effect i