Annular blowout preventer for drilling and workover

The invention discloses an annular blowout preventer for drilling and workover. The annular blowout preventer comprises a shell; a top cover is arranged at the upper end of the shell; a piston is arranged in a cavity in the shell; a spherical rubber core is arranged at the upper end of the piston; the outer wall in the middle of the piston extends horizontally to form a circular boss; a fender ring is arranged between the upper part of the piston and the inner wall of the shell; a rectangular seal ring is arranged between the outer wall of the fender ring and the inner wall of the shell; a claw block is radially arranged between the top cover and the shell; one end of the claw block is connected with a claw block supporting screw; a claw block screw sleeves the periphery of the claw block supporting screw; the claw block serves as a connection load bearing part between the shell and the top cover; the radial position of the claw block in the shell can be adjusted by rotating the claw block screw and the claw