A self-circulation helium liquefaction system with five 4 K G-M cryocoolers

A self-circulation helium liquefaction system (SCHLS) with five 4 K G-M cryocoolers is developed to supply liquid helium (LHe) for SECRAL (a superconducting ECR ion source used in Lanzhou city, China). LHe is vaporized in SECRAL and warmed up to room temperature. SCHLS will re-liquefy the helium gas at a rate of 83.2 L/day under normal atmosphere pressure. With SCHLS, SECRAL system can run online without any interruption of refilling LHe.

Research highlights
► A self-circulation helium liquefaction system (SCHLS) with five 4 K G-M cryocoolers is developed.
► Helium gas is re-liquefy at a rate of 83.2 L/day under normal atmosphere pressure.
► With SCHLS, SECRAL system can run online without any interruption of refilling LHe.
► SCHLS is suitable for a lot of the devices whose consumption of LHe is lower than 80 L/day.