Abstract: There is provided apparatus (100) for forming a tube (9) by bending a metal sheet (11). The apparatus (100) comprises a forming station (102) comprising a forming pin (101) around which a metal sheet (11) can be wrapped and a plurality of form fingers (110, 120, 130, 140) radially spaced around the forming pin (101) and moveable relative thereto. Also provided are electrode emission source components (1) The components (1) comprise an open ended tube (9) and a-cap (13), wherein the tube (9) is formed from* a metal sheet (11) which is formed into a tubular configuration. Further provided are electrodes, electrical apparatus and methods of forming tubes.

Abstract: There is provided an electrode apparatus (1) comprising an emission source component (12) and a reservoir (4) of active material for replenishing active material of an emission surface of the source component (12) and/or for providing active material to the source component (12). Also provided are electrode assemblies, electrical apparatus comprising these and methods of manufacturing them.