A slide valve for chemical and/or petrochemical plants, in particular of the round, oval or flat slide valve type, having a locking device (11) which is movable by a slide rod (12) into an open and closed position, and a drive which has an electric motor (13) for adjusting the slide rod (12), the locking device (11) having two lock plates (14, 15), between which a wedge arrangement (16) for pressing the lock plates (14, 15) against body seal seats (17) of the slide valve is arranged and connected to the slide rod (12), wherein the drive has a spindle drive (18) which is aligned with the slide rod (12) and connected thereto for transmitting an actuating force.