Lowest Documented Temperature for SA 350 LF2
Lowest Documented Temperature for SA 350 LF2
(OP)
We have a situation with a customer which we have built an instrument (probe) for connecting to a cryogenic pipeline (LNG). We have built this probe from SA 350 LF2 and our customer is now demanding we verify the SA 350 LF2 will be sufficient to handle temperatures as low as 150F. I have attached an email from a flange manufacture indicating the SA 350 LF2 is acceptable in this range but I been unable to support his comments with any documentation.
Any help you might be able to give will be much appreciated.
Any help you might be able to give will be much appreciated.





RE: Lowest Documented Temperature for SA 350 LF2
Your customer is absolutely correct in asking for CVN impact verification. If you review ASME SA 350, for Grade LF2 impact testing assuming Class 2, is required at -50 deg and at O deg F for Class 1.
RE: Lowest Documented Temperature for SA 350 LF2
I do not disagree with you as I have read the material specification thoroughly due to using these materials and other materials / specifications for the PED. We have consulted with many pipeline companies such as El Paso in determining what materials for flanges they use in LNG service which at times may see below -100F and their engineers tell us SA 350 LF2 which confuses me when I see the CVN impact temperature for LF3 being -150F.
RE: Lowest Documented Temperature for SA 350 LF2
The CVN testing of this material is mandatory to assure complinace with the CVN notch toughness requirements at the required service temperature.
Lower than -50 deg F service would require Grade LF3 material as specified in SA 350, not Grade LF2. I don't know what is so confusing about this????????
RE: Lowest Documented Temperature for SA 350 LF2