CRYOGUY Education in Cryogenics
Light helium refrigeration
This session has been set up on demand of CERN’s operator team in order to give an overview of helium refrigeration. A very pragmatic session (no TS diagrams).
Whom for?
Beginners in helium refrigeration who might be “drowned” by the big amount of detailed information that is provided during the standard helium refrigeration session.
Some people who are not directly involved in the operation of a cryogenic system (as electrical, control or maintenance persons) but, however, need to know how such a system operates.
How long?
This educational session takes place within a two and a half-day period (total time is around 18 hours).
Theory, cycles
  • General reminders
  • Theory of heat exchangers
  • Basic cycles
  • Liquid nitrogen pre-cooling
  • Thermal shield cooling
  • High power cycles
  • Refrigeration cycles for temperatures lower than 4.5 K
Technology and operation of the main components
  • Helium compression with oil lubricated screw compressor
  • The oil management system
  • The heat exchangers
  • The cryogenic expansion turbine
  • Process control
  • Process control in helium refrigeration
  • Transient situations
Helium purity
  • Pollution of helium
  • Purification by adsorption
  • Purification by cryo-trapping
  • Helium analysis
Operational checks and maintenance

Visit of a local cryogenic helium plant