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DIFF Subclass Not Allocatable
F25J

LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT

Introduced: September 1968

Description

F25J covers apparatus and processes for liquefying, solidifying, or separating gases and gaseous mixtures through combined application of pressure and low-temperature treatment. This subclass encompasses cryogenic separation technologies including rectification columns, heat exchangers, expansion devices, and complete liquefaction plants for industrial gases such as nitrogen, oxygen, argon, and natural gas. The classification includes both the refrigeration systems and mechanical equipment necessary to achieve the required pressure-cold conditions, as well as methods for air separation and purification of gas streams.

Title

Titles differ between systems:

IPC: LIQUEFACTION, SOLIDIFICATION, OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT

CPC: LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT

Full Title

Full titles differ between systems:

IPC:

LIQUEFACTION, SOLIDIFICATION, OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT

CPC:

LIQUEFACTION, SOLIDIFICATION OR SEPARATION OF GASES OR GASEOUS MIXTURES BY PRESSURE AND COLD TREATMENT

CPC subdivides this area 6x more granularly than IPC with 14 additional codes.

14 codes are CPC-only extensions.

Note: 14 CPC extensions are marked as secondary classification only.

1 shared codes have differing titles between IPC and CPC.

Child Classifications

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