Protective device of steam turbine

The utility model provides a protective device of a steam turbine. The protection device of the steam turbine comprises a protection device body, and the protection device body comprises an industrial sound absorption and insulation cover, an air extractor protection shell and a motor protection cover; the dust removal shell is detachably arranged on the air inlet side, away from the industrial sound absorption and insulation cover, of the air extractor protection shell through screws. The air flow sensor is arranged on the dust removal shell, and the sensing end of the air flow sensor extends into the dust removal shell; the assembly shell is detachably arranged in the dust removal shell and located on the air inlet side of the air flow sensor; and the flow guide edge is fixedly mounted on the air inlet side of the assembly shell. The protection device of the steam turbine has the advantages that cooling air can be subjected to dust removal treatment, and the influence on wave type sound absorption cotton is