A mechanical sealing and flushing method and device of a seafloor mud lifting pump comprises a
seawater pump, a pump outlet, a pump inlet, an
impeller, an O-type ring and a
seawater flushing
pipe. The
seawater pump is arranged in seawater and is coaxial with a motor, the pump outlet is formed in the seawater pump, the pump inlet is formed in a front end cover of the seawater pump, the
impeller is arranged inside the seawater pump and is connected with a
motor shaft through keys, the O-type ring is arranged between the seawater pump and the front end cover of the motor, and the seawater flushing
pipe is connected with the pump outlet and a sealing and flushing opening. The seawater pump is immersed in the seawater, the pump inlet is directly communicated with the seawater, the seawater is boosted through the effect of the
impeller inside the seawater pump, and seawater flowing and flushing to a sealing face are achieved. The mechanical sealing and flushing method and device of the seafloor mud lifting pump is simple in structure, sealing liquid does not need to be drawn from a sea surface to flush a circulation pipeline, the problem of sealing
face flushing of the seafloor mud lifting pump of a seafloor mud lifting drilling well can be effectively solved, meanwhile, the mechanical sealing and flushing method and device of the seafloor mud lifting pump can be applied to ocean mining and other seafloor
solid-liquid two-phase conveying pumps, and the demands for mechanical sealing and flushing of
deep sea seafloor
solid-liquid two-phase conveying pumps are met.