Compression Strength of Composite Tubular Struts for Superconducting Magnetic Energy Storage
Large radial forces are generated during operation of a superconducting magnet used for energy storage. Filament wound glass reinforced epoxy tubular struts have been proposed for transmitting the magnetic loads from the magnet which operates at 1.8 K to the outside wall of the vacuum chamber which is at 300 K. High strength, low thermal conductivity and cost were the drivers in selecting a composite strut design. An extensive test program was performed to provide a data base for developing a design method for composite cylinders in axial compression. Studies included determination of ultimate loads, ultimate strains and modulus of elasticity, the effects of end cap configurations, creep tests, fatigue tests and a life cycle test on a full size strut under simulated operating conditions. Ultimate compressive strength of 862 MPa was achieved at room temperature on 152.4 mm diameter struts.
KeywordsUltimate Load Vacuum Vessel Composite Cylinder Superconducting Magnetic Energy Storage Filament Wound
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