Apparatus and method for supporting tubes in extrusion lines. A tube support mechanism is adaptable to a respective tube diameter being transported, and includes at least one articulated link chain configured to rest against at least part of a circumference of a tube, and comprises chain links having end faces directed toward the tube. The chain links are disposed in at least two planes, and overlap one another from plane to plane in overlap zones. The chain links are pivotably connected to one another in such overlap zones. Facing ends of the chain links of a given plane of chain links have identical gear wheel contours that mesh with one another. Adjustment of the tube support mechanism from one nominal diameter to another is effected by a pressure effect, onto the tube support mechanism, of a conical tube transition piece that results during the change in diameter during continuing operation. An angle of contact of the tube support mechanism against a tube successively changes.