A method for the extrusion of preforms, which, on the underside of an extrusion die, emerge vertically from an annular nozzle gap of the extrusion die, and are expanded by blow moulding to form hollow plastic bodies, wherein the geometry of the nozzle gap is altered during the extrusion of the preforms, wherein at least one elastically deformable sleeve is used for purposes of altering the nozzle gap geometry, which sleeve is arranged within the extrusion die such that it can be adjusted horizontally, and forms an inner peripheral surface or an outer peripheral surface of the annular gap, wherein at least two program-controlled actuators (8, 8') are used for the horizontal adjustment and the elastic deformation of the sleeve, which actuators (8,8') act on the perimeter of the elastic sleeve at force application points (9, 9') that are offset by 180°, and wherein the sleeve is horizontally adjusted by movements of the force application points (9, 9') in the same direction, and is elastically deformed by movements of the force application points (9, 9') in opposite directions, and/or by differing magnitudes, - wherein the adjustment paths of the actuators (8, 8') are controlled using a program controller, which runs synchronously with the extrusion of the preforms, and which determines the movements of the force application points (9, 9') by the superposition of two movement components (14, 15), - wherein the first movement component enables a symmetrical deformation of the sleeve, and consists of opposing, and, in terms of magnitude, equally large, adjustment paths of the force application points (9, 9'), - wherein the second movement component enables a horizontal positional displacement of the position of the sleeve and consists of adjustment paths of the force application points (9, 9') in the same direction and of the same magnitude, characterised in that - the available adjustment path of the actuators is greater than a permissible deformation stroke for the deformation of the sleeve, and - wherein for the first movement component a limiting value for the maximum permissible adjustment path is specified by means of the program controller. - wherein the adjustment paths of the actuators (8, 8') are controlled using a program controller, which runs synchronously with the extrusion of the preforms, and which determines the movements of the force application points (9, 9') by the superposition of two movement components (14, 15), - wherein the first movement component enables a symmetrical deformation of the sleeve, and consists of opposing, and, in terms of magnitude, equally large, adjustment paths of the force application points (9, 9'), - wherein the second movement component enables a horizontal positional displacement of the position of the sleeve and consists of adjustment paths of the force application points (9, 9') in the same direction and of the same magnitude, - the available adjustment path of the actuators is greater than a permissible deformation stroke for the deformation of the sleeve, and - wherein for the first movement component a limiting value for the maximum permissible adjustment path is specified by means of the program controller.