in another direction at a 2 a similar connection is shown between the inner cylinder shell 2 and the outer cylinder shell 1 the only difference is that here lying opposite the radial projection 24 in each case one tangentially milled seat 26 is provided on the outer circumferential face 10 of the inner cylinder shell 2 as a result improved support can be achieved at a 3 a connection is shown which largely corresponds to the connection of a 2 the only difference is that the diameter of the screw holes 22 and the screws 23 is smaller here than the corresponding diameters at a 2 for example screws of the size m 10 can be used at a 2 and screws of the size m 8 can be used at a 3 the smaller screws save weight in comparison with the larger screws a further variant of the connection of a 3 is shown at a 4 the difference is that the seat 26 here is not milled tangentially but at an angle of 2 u00b0 with respect to the tangential direction the milling serves to clamp the outer cylinder shell 1 with respect to the inner cylinder shell 2 for this purpose after it has been fed onto the inner cylinder shell 2 the outer cylinder shell is rotated in the direction of the rising.