Dear Richard,

Thank you for your response. As specified in the code, I think properties for lower temperature than 32 deg F are to be selected by the stress engineer. As my project allows the use of API 5L X60 only if the impact test results are conforming the specified limit, in my opinion, it should be justified to use same properties as 32 deg F for lower temperatures.

If there is anything I misunderstood, please let me know.