When i use pipe material API 5L X52 in ASME B31.8 for design condition -29 deg Celsius, i am getting an error message saying that Temperature is outside allowable range for this material. I am confused, as per code pipe material upto -29 deg C is allowed. Can any one help to resolve this issue?.

It is only the recent Editions of B31.8 that permit temperatures below 32F. Check the "Quick Reference Guide" for your version of CAESAR II to see what Edition of B31.8 is supported.

Thank you for your response Richard. My version of CAESAR II is supported with November 30, 2007 edition and this edition is allowing pipe material up to temperature -20 deg F (-29 deg C).