This proposal for an SBIR project is to design and develop a simple system to assemble and seal the vacuum joints of SRF Cavities. The System substitutes highly sprung,C shaped spring clamps for bolts and nuts for applying sealing force on the metallic gaskets of cavity flanges. The system minimizes particle generation during assembly in the clean room by avoiding the rubbing/shedding contact experienced during torquing lubrication-free bolts. The highly-stressed spring clamps produce the high force necessary to suitably crush metallic seal rings and to maintain the resulting seal through handling and cryogenic cycles. Phase 1 accomplishes the engineering design of a clamp and its clamp opener, makes developmental clamp and clamp opener prototypes and finally validates that the spring clamps can establish and maintain the vacuum seal on flange joints of an existing research cavity through handling, cryogenic cycles, superfluid challenges and powering cycles.Phase 2further optimizes the clamp design, flange design (perhaps fewer clamps and thicker flanges) and assembly tooling to assemble and seal the flanges of multiple cavities in a clean room, validates any changes and commercializes the system purchase or for licensing.The Phase II work would be in coordination with a partner organization where the first High Force Spring Clamp sealed Cryomodule would be assembled and test
