Patent ID: 7608151

Claim:
A system for uniformly coating the internal surfaces of a section of a conductive workpiece comprising: first and second members configured for insertion into said section of said workpiece and dimensioned to isolate a localized interior section of said workpiece there between, said localized interior section being a cross sectional region of section into which said first and second members are inserted; wherein said first and second members include a sealing means for physically and electrically isolating said conductive workpiece from said first and second members and for sealing said localized interior section from a remainder of said section of said workpiece; a biasing system connected to said first and second members such that said first and second members are at a same voltage, said biasing system being connected to said workpiece such that said workpiece functions as a counter-electrode to said first and second members; a gas source inlet connected to one of the said first and second members for flowing a gas containing a coating material into said localized interior section of said workpiece such that exposure of said workpiece to said gas is limited to said localized interior section; a vacuum source outlet connected to the other of said first and second members for evacuating said gas from said localized interior section; and a means for varying the position of said first and second members along a length of said workpiece.