Method and apparatus for reforming a container

This invention provides a method for expanding at least a portion of a cylindrical sidewall of a generally cylindrically shaped, electrically responsive, metallic body. This method comprises the steps of retaining at least a first portion of the metallic body, disposing a coil of electrically conductive material inside the metallic body, and energizing the coil to create an electromagnetic force sufficient to expand at least a portion of the generally cylindrical sidewalls of the metallic body outwardly of the original generally cylindrical shape. During such expansion, a fluid is introduced between the coil and the inside surfaces of the container to maintain positive gauge pressure as the sidewalls expand. This invention also provides an apparatus for expanding at least a portion of a cylindrical sidewall of a generally cylindrically shaped, electrically responsive, metallic body. The apparatus comprises a retaining mechanism for holding the metallic body, a coil of electrically conductive material, structure for disposing the coil inside the metallic body, and structure for energizing the coil sufficient to expand at least a portion of the sidewall of the metallic body. Means for maintaining positive gauge pressure during expansion is also included in the apparatus.