Innovative Fabrication Techniques for Aerospace Propellant and Pressurant Tanks

To be economically attractive, weight and performance for small earth-to-orbit launch systems and station keeping space vehicles must be improved at significantly lower costs, while maintaining required payloads. A major weight and cost factor in any of these devices is the tankage for propellants and pressurant gases. Innovative and proven manufacturing technologies such as electroforming have been overlooked as means meeting these needs. It offers the means to fabricate seamless tanks with no property degrading welds. In conjunction with filament winding, electroforming can produce improved tanks in greatly reduced time frams because it can produce the mat-erial and the net shape simultaneously. Nickel-low cobalt alloys are currently avail-able through electroforming with yield strengths in the 100 to 150 ksi range. Efforts to develop titanium electroforming are expected to enhance the competitiveness of electroforming to produce much lighter tankage by virtue of the low density of this metal. Capability to electrodeposit bonded liners in filament wound outer shells will provide further fabrication innovations for the tank designer.