Abstract: A tube expander includes a housing, a generally cylindrical cage and a mandrel movably disposed within the bore of said cage. The expander further includes an indexing system to automatically axially advance the cage relative to the housing in a step by step manner.

Abstract: A roller tool having material-deforming rollers the axis of rotation of which extends lengthwise of and forms an angle with the longitudinal axis of a tube to be secured, is inserted into that portion of the tube which is located within the confines of a passage of the support. The roller tool is then rotated in contact of its rollers with the inner circumferential surface of the tube, so as to form at one axial location of the tube a corresponding outward face deformation of the tube in the passage. During this time, axial displacement of the roller tool relative to the tube is prevented until the outward deformation has reached a desired dimension in direction radially outward of the tube. When this dimension is reached, the rotation of the roller tool is continued but the roller tool is now also permitted to advance axially of the tube so as to form a second outward deformation in the latter axially adjacent the first one. An apparatus for carrying out the method is also disclosed.