Standard compressor casing materials are generally good for temperatures of -20 to -50°F. Below these temperatures, standard materials become brittle, and materials with improved low temperature properties must be used.
Nickel based steel alloys are generally used, with suitable alloys available for both fabricated and cast casings, for temperatures to approximately -150°F. Special nickel alloys and austenitic stainless steels may be used for temperatures to -320°F.
Also review other component materials for compatibility with the operating temperature range. The materials appendix of API 617 is an appropriate guide for material selection since temperature limits specified indicate limits commonly applied by compressor manufacturers.
An unusual example of the application of low temperature material requirements is an air compressor located in a cold climate region. Although this compressor might be located in an enclosed (even heated) building, it could be exposed to inlet air temperatures well below -50°F. Suction throttling would further reduce inlet temperatures.
Where reduced maximum yield strength and hardness are specified, apply the same requirements to any welding and repair procedures.