A corrugator device for shaping thermoplastic corrugated pipes from a tube of molten plastics material emerging from an extrusion device may include molding jaws, grippers for returning the molding jaws from the end of a molding section to the start of the molding section, and a mold release device. The mold release device is arranged at the end of the molding section, and has a motor-driven rotary disk for interacting with the pair of molding jaws. The pair of molding jaws, which has reached the end of the molding sections, is moved apart by means of first and second drivers formed on the motor driven rotary disk.