Method for surface-finishing plastically-deformed metal liner and metal liner surface-finished by the method

A method for surface-finishing one or more metal liners, each of which is formed by plastic deformation to be axially symmetric in shape, comprising a body section shaped to be a generally hollow cylinder with a predetermined wall thickness elongated in an axial direction;

• at least one dome section formed seamlessly contiguous to one end of the body section;
• and at least one neck section that is extruded seamlessly contiguous to the at least one dome section to form a generally narrow tube having a passage therein to channel a content, wherein the surface has wrinkled textures generated during the plastic deformation, the method comprising:
• chemical milling,
• wherein the method comprises:
• housing the one or more metal liners in a rack to hold and secure the one or more metal liners therein to have a unit of the rack and the one or more metal liners housed therein;
• first immersing the unit in a bath of an etching solution for the chemical milling for a length of immersion time;
• showering with water the one or more metal liners of the unit while the unit is being lifted from the bath;
• first washing with water the one or more metal liners of the unit placed outside the bath of the etching solution;
• measuring wall thicknesses at predetermined locations of the one or more metal liners;
• repeating the first immersing through the measuring until a predetermined smoothness is obtained, wherein the length of immersion time is adjusted according to the measured thicknesses;
• second immersing the unit in a bath of a deoxidizing solution;
• second washing with water the one or more metal liners of the unit placed outside the bath of the deoxidizing solution;
• rinsing with deionized water the one or more metal liners of the unit;
• and
• taking out the one or more metal liners from the rack.