A sleeve containing an explosive charge which is explosively welded along a tapered end to the inner surface of a tube for repairing a damaged section of the tube. No mechanical support is needed along the outer surface of the tube despite the explosive expansion and welding of the sleeve. The explosive charge is tapered at the end of the sleeve. A charge assembly for carrying the explosive charge includes a flange for centering the sleeve in the tube and for establishing a stand-off distance between the sleeve and the tube.