In-cabin dredging pump applying water seal structure at water inlet end

The utility model relates to an in-cabin dredging pump applying a water seal structure at a water inlet end, in particular to a large-size in-cabin dredging pump. The in-cabin dredging pump comprises a bracket body, wherein a bearing assembly is fixedly arranged on the bracket body, a pump shaft is supported by the bearing assembly, a pump body is fixed at the front end of the bracket body, a pump cover is arranged at the front end of the pump body, an impeller is arranged in the pump body and is arranged at the front end of the pump shaft, an impeller water inlet is arranged at the front end of the impeller and is coaxial to the pump shaft, the inner wall of the pump cover is matched with a front lining plate, a water inlet pipe cavity is arranged at the center of the pump cover and is coaxial to the pump shaft, the in-cabin dredging pump is characterized in that the water inlet pipe cavity is a step hole with a large internal part and a small external part, the step hole is matched with the inner wall of a