More than 8600 Superconducting magnets will equip the SSC (Superconducting Super Collider) accelerator and about 3000 will be used for the LHC (Large Hadron Collider). Those magnets require a specific piping system with about 10 different lines ranging in diameter from 43 to 150 mm which are meant to provide ultra-high vacuum and helium cooling down to 1.8 K. One of the joining methods under consideration is welding. We have developed another solution which allows a quick and ultra-clean joining method, using a chain-clamp on tapered flanges sealed with a HELICOFLEX® resilient metal seal.