Isogrid Vacuum Shell for Large Superconducting Solenoid

An aluminum isogrid outer shell of an annular vacuum vessel for a superconducting solenoid has been designed. The shell was about 4 m in diameter and 9 m long. Isogrid was used to reduce the effective or weight average thickness of the shell. The design requirement was a calculated collapse pressure of 2 atm. If solid aluminum plate were used, the shell would be 27 mm thick; using isogrid lowered the thickness to 10.5 mm. An isogrid shell 4.12 m OD by 2.34 m long was designed, fabricated, and tested as the outer shell of the vacuum vessel for a prototype of the solenoid.