F
SECTION F — MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  
LIGHTING AND HEATING
 F25
REFRIGERATION OR COOLING; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION OR SOLIDIFICATION OF GASES
 F25J
LIQUEFACTION, SOLIDIFICATION, OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT (cryogenic pumps F04B 37/08; gas storage vessels, gas-holders F17; filling vessels with, or discharging from vessels, compressed, liquefied, or solidified gases F17C; refrigeration machines, plants, or systems F25B)
 F25J 1/00
Processes or apparatus for liquefying or solidifying gases or gaseous mixtures
 F25J 1/02
·  requiring the use of refrigeration, e.g. of helium or hydrogen
 F25J 3/00
Processes or apparatus for separating the constituents of gaseous mixtures involving the use of liquefaction or solidification
 F25J 3/02
·  by rectification, i.e. by continuous interchange of heat and material between a vapour stream and a liquid stream (F25J 3/08 takes precedence)
 F25J 3/04
·  ·  for air
 F25J 3/06
·  by partial condensation (F25J 3/08 takes precedence; by rectification F25J 3/02)
 F25J 3/08
·  Separating gaseous impurities from gases or gaseous mixtures (cold traps B01D 8/00)
 F25J 5/00
Arrangements of cold-exchangers or cold-accumulators in separation or liquefaction plants (heat-exchangers per se F28C, F28D, F28F)