Abstract: One end of a metal tube is joined tightly to a plate by locating the end portion loosely within an aperture in the plate and, in a single pressing operation, expanding the tube wall into engagement with the periphery of the wall of the aperture, buckling the tube wall to form a double-walled flange or collar against the side of the plate opposite the free end of the tube and crimping the free end of the tube radially outward to form a flange against the other side of the plate. Apparatus for carrying out the method includes a device for clamping the tube from the sides and a die which enters the free end of the tube for carrying out the expanding, buckling and crimping steps.