Ball valve with double-sealing structure

The invention discloses a ball valve with a double-sealing structure, which comprises a valve body, a left end cover and a right end cover which are arranged on the two sides of the valve body and connected with the valve body to form a cavity, and a valve shaft assembly mounted on the valve body, and further comprises a valve seat assembly used for being mounted on the left end cover and the right end cover, the sealing ring is in contact with a ball body in the valve shaft assembly to form a sealing pair; the valve seat assembly comprises a sealing ring and a valve seat of a step-shaped structure, the left end cover and the right end cover are provided with step holes matched with the valve seat, the valve seat is provided with an arc-shaped face used for being matched with the ball body, an installation groove is formed in the arc-shaped face, and the sealing ring is installed in the installation groove and then makes contact with the ball body to form a first sealing structure. According to the valve, a d