Volute structure and centrifugal compressor

The invention relates to a volute structure. The volute structure comprises a box body, wherein the box body is provided with an air supplementing joint, and a volute is arranged in the box body; thevolute structure further comprises a first partition and a second partition which are detachably connected with the box body, wherein the first partition plate, the second partition plate and the volute are arranged at intervals along the axial direction of the box body, and the first partition plate, the second partition plate and the box body define an air supplementing cavity; and the air supplementing joint communicates with the air supplementing cavity, the second partition plate and the box body define a diffuser communicating with the volute, the first partition plate and the second partition plate are both ring-shaped, and the inner edge of the second partition plate extends to form a bushing attached to the first partition plate and used for mounting an impeller. The volute structure is convenient to disa