Abstract: A vibration-decoupling flange connection in an exhaust gas pipeline of motor vehicles includes flanges pretensioned by means of a tensioning device with springy means so as at least to swivel and to seal on a position, corresponding to a precalculated position of pipe members to be connected. The tensioning device is mounted when the exhaust gas pipe is closed and forms a clamp. The clamp legs of the clamp overlap under pretension the opposite flange sides with clamp curves of the clamp legs and extend over a circumferential angle of more than 180 degrees. The clamp curves exhibit supports, spaced in the circumferential direction. The clamp legs are separate components, which, when fitted together, can be fixed in position relative to each other by locking.