Marine underwater rotary-digging-type harvesting device

The invention relates to a marine underwater rotary-digging-type harvesting device, wherein a rotary digging device is fixedly connected with a front fixing plate; an outlet at the rear part of a mud absorption bucket is connected with the front end surface of a rotary steel sleeve through a front connecting pipe; the front end of the rotary steel sleeve and the front fixing plate are welded into a whole; the middle of the rotary steel sleeve is provided with a protruding shoulder; the periphery of the protruding shoulder is provided with a shaft sleeve and a fixed steel sleeve; a Haff flange is installed on the front end opening of the fixed steel sleeve; a front baffle ring is arranged between the front end faces of the shaft sleeve and the protruding shoulder and the Haff flange; the rear end opening of the fixed steel sleeve is welded on the rear fixed plate; a rear baffle ring is arranged between the rear end surfaces of the shaft sleeve and the protruding shoulder and the rear fixed plate; the rear fixed plate is fixed on a bridge rack; a seal ring is arranged between the rotary steel sleeve and the rear fixed plate; the center of the rear end surface of the rear fixed plate is provided with a rear connecting pipe; the outlet of the rear connecting plate and an absorption opening of a mud pump are connected; and the rotary steel sleeve and the center of the rear fixed plate are respectively provided with through holes extending along the axes of the rotary steel sleeve and the rear fixed plate. The device can adjust the angle of the underwater harvesting device, and the dredging efficiency is improved.