A Simon-Type Helium Liquefier with Transfer Siphon

Abstract

A helium liquefier utilizing the Simon expansion process is described. The liquefier is provided with a transfer siphon, so that the liquid produced is delivered into an external cryostat. By locating the expansion valve at the end of the transfer siphon, the cold gas released during the expansion is utilized in precooling the receiver, so that rather high yields are obtained. From the expansion chamber of 400-cm3 capacity, 310 cm3 of liquid are collected in the receiver.