the length of the spacing pipe 10 structurally determines the length of the tie rods 13 14 the length of the tie rods 13 14 influences as mentioned their yielding or bending at right angles to the center axes 7 and or 8 so that thermal stresses between the vessel 1 and the annular support 2 are intercepted without the risk that the vessel might be displaced with a jolt in the annular support 2 during the tilting process the tie rods may in an extreme case adopt a slight s shape to this end the tie rods 13 and 14 are either rods of full cross section rods with tubular cross section or bundles of individual wires when mounting the vessel 1 in the annular support 2 the package consisting of the bearing extension 5c spacers 9a 9b abutment 6 and spacer pipe 10 is compressed with the desired initial stress force and this condition is fixed by means of clamp nuts still to be described at the clamp heads 11 and 12 by fastening such procedure is followed for each of the initial stress units in principle it is possible to execute a two or multi stage initial stress process either on the side of the clamp head 11 only or on the side of the clamp head.