Labyrinth seal is adopted for both ends of the bowl of the standard type of the LW series, which is simple yet efficient. After separation, the solid phases are pushed to the solid discharge outlet through a spiral and then discharged out of the bowl under the action of the centrifugal force generated from high-speed revolution, and the clarified liquid is discharged out of the overflow port at the big end of the bowl. Featuring simple operation, stable operation, high efficiency and high automation, and continuous working of 24 hours, this type is widely applied.