Novel built-in double-eccentric inclined clack check valve and using method thereof

The invention discloses a novel built-in double-eccentric inclined clack check valve which comprises a valve body installed in a medium pipeline so that a medium can flow; the valve clack is rotationally installed in the valve body through the valve clack shaft so as to control on-off of media in the valve body. The valve seat is installed in the valve body, and when the valve clack is in a closed state, the outer edge of the valve clack is connected with the valve seat in a sealed mode. The torsion spring has a slow opening state and a seat returning state, when the valve clack is opened under the action of medium pressure, the torsion spring assists the valve clack in slow opening, and vibration caused by medium pressure fluctuation is eliminated; and when the valve clack loses the medium pressure, the torsion spring assists the valve clack to return to the seat and enables the valve clack to be hermetically connected with the valve seat. According to the novel built-in double-eccentric inclined clack check