Abstract: A chromium regeneration apparatus (10) is disclosed for regenerating spent chromium solution by oxidizing trivalent chromium to hexavalent chromium. The apparatus is provided with a tank (42) forming a reservoir full of spent chromium solution. A number of anode assembles (46) are supported on the tank within the reservoir with each assembly including two frame sections (70, 72) bolted together along their sides and bottom with two separate cation selective membranes (100, 102) secured therebetween. Membrane tensioners (104) are inserted between the membranes to separate them and urge them against the frame sections over openings in the frame sections to define an anode chamber. An anode and cathode are provided to a generate a current flow therebetween to regenerate the solution.

Abstract: An improved method for forming an assembly of laminated materials is provided. The method eliminates an necessity to evacuate a package or position the assembly in an autoclave for forming. In the method, the assembly (14, 70) is positioned against the die face of a rigid die (12, 72). A cavity of essentially constant volume is formed about the die and assembly and encloses the side of the assembly opposite that in contact with the rigid die. The cavity is filled with expandable spheroids (56). The spheroids are expanded to provide the necessary force on the assembly to urge the assembly against the rigid die to form the completed assembly. Preferably, the expandable spheroids (56) are thermally expandable and can comprise, for example, silicone rubber having a coefficient of thermal expansion of about 50.times.10.sup.-5 inches per inch per degree Fahrenheit.

Abstract: Disclosed is a method and apparatus for joining a metal skin to an internal structure comprising forming the metal skin to a permanent desired contour; assembling a lattice of ribs and spars and bonding the lattice to the contoured skin and subsequently forming the completed structure by bonding a pair of skin-superstructure assemblies together. Also disclosed is a diaphram designed to apply pressure to the skin only along structurally supported area of the skin to prevent damage.