to the pulling in direction 15 which fundamentally contributes to the stabilization of the spatial position of the bundle 1 of tubes in still more precisely described form in the fig2 is now once again to recognize more exactly in a cut top view the construction of a flange 3 the flange 3 is here arranged in a drilling channel 9 which has resulted of the expansion by the expanding head 5 and pulling in through the expansion cone 4 the largest dimensions of every flange 3 are essentially identical with the dimensions of the walls 16 of the drilling channel 9 so that every flange 3 at least in sections fits closely to the walls 16 of the drilling channel 9 the flange 3 is built up essentially three partly in which a central middle part 20 is plugged in between the great upper and the smaller below arranged tubes 2 in the middle part 20 respectively semicircular openings 23 are provided in which the tubes 2 can be inserted respectively on the upper side of the upper tubes 2 and sub sided of the lower tubes 2 further parts of the flange 3 formed like clamps are to be seen namely a upper part 21 und a lower part 22 in this upper part 21 und the lower part 22 corresponding also semicircular openings 23 are let in which corresponds with the semicircular openings 23 of the middle part 20 and complete these to a full circle the diameters of these openings 23 correspond essentially to the diameter of the respective tube 2 in which the dimensions are chosen so that the tubes 2 are friction lockedly held by means of.