TUBE EXPANDING AND FLANGE-FORMING TOOL

A tool for expanding a tube into engagement with a wall of a hole in a plate and simultaneously forming a flange on the end of the tube has a mandrel having a tapered distal portion. The mandrel receives for rotation and axial displacement a tubular cage. The cage carries expanding rolls, each of which is supported for rotation in a slot in a distal portion of the cage, is displaceable radially, is in rolling engagement with the tapered portion of the mandrel and the tube when the tool is in operation, and is skewed at a small angle to the mandrel axis so as to impart traction to the cage and the mandrel and draw them distally into the cage upon rotation of the mandrel. A forming roll is supported for rotation and for displacement radially with respect to the mandrel axis in an opening in the cage and has: at least one conical following surface that is in rolling engagement with the tapered portion of the mandrel; a conical expanding surface that is in rolling engagement with the tube; a forming surface immediately adjacent the expanding surface proximally that is in rolling engagement with the tube; and a conical thrust-receiving surface at a proximal end. Axial force is transmitted from the cage to the thrust-receiving surface by an annular two race axial thrust bearing, which is supported on and surrounds the cage proximally of the forming roll.