The demand for lightweight, high-current-density electrical power on U.S. Navy ships is driving development of superconducting technologies including motors, generators, and degaussing cables. Vacuum insulation systems work in concert with these devices to minimize heat leak into the cryogenic space. Typically, vacuum spaces are maintained manually every 5-10 years, at an average cost of $550,000 over the life of a ship.

Air Squared proposes to combine a turbomolecular backing pump with two-stage scroll vacuum pump acting as a roughing pump.Air Squared proposes to combine a turbomolecular backing pump with two-stage scroll vacuum pump acting as a roughing pump.To minimize the maintenance costs associated with shipboard vacuum-insulation systems used in cryogenic and superconducting applications, the U.S. Navy has initiated a project with Air Squared to demonstrate a small, autonomous vacuum-maintenance device. The Phase I project, awarded Small Business Innovation Research (SBIR) funding, is expected to result in development of a system that will replace the relatively large autonomous vacuum systems currently in use.

Using SBIR funding, Air Squared says it intends to demonstrate the use of a compact, robust vacuum-pumping setup that combines a two-stage scroll vacuum pump with an integrated turbomolecular backing pump. The vacuum pump will act as a roughing pump, delivering 50-mTorr vacuum to the backing pump. The backing pump then delivers 0.1 mTorr. The result, says Air Squared, is a compact and cost-effective autonomous vacuum system that does not sacrifice performance or reliability.

The Navy has identified more than a dozen critical performance metrics (CPMs) fir the vacuum system. The Phase I effort aims to accomplish six of these:

· Provide a vacuum below 0.1 mTorr

· Allow for system pump-down from 0.1 Torr to 0.001 mTorr

· Discharge to atmospheric pressure

· Have a size less than 35 cubic inches

· Cost less than $2,000

· Weigh less than 5 lb.

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