Oil extraction type thin oil lubrication vertical seawater lift pump

The invention discloses an oil extraction type thin oil lubrication vertical seawater lift pump which comprises an overflowing assembly, a rotor assembly, a bearing box assembly, a sealing assembly and a motor support. The flow passage component is composed of a lower sliding bushing, a suction section, a suction section opening ring, a flow guide shell, a sliding bushing, a flow guide shell rear opening ring, a flow guide shell front opening ring, a final-stage flow guide shell, a connecting pipe, an upper sliding bushing, an upper sliding bushing seat and an outlet section. An independent oil extraction type self-circulation and self-lubrication mode is adopted in a large oil storage chamber of the bearing box body, the bearing can be effectively lubricated, the oil temperature can be reduced in the circulation process, the service life of the bearing can be prolonged, meanwhile, the impeller is located between the two sliding bushes, the whole rotor is well supported through the multi-point supporting slid