Carbon Steel Flange for class API5000

[Redpipe]

As per API 6A and ASTM A105 standard, carbon steel A105 cannot be used for class API5000.

However, when I saw some piping specification, it specified carbon steel A105 for pipe wall thickness less than 1". Also I found many carbon steel flowlines using A105 flange when connected to X'mas tree.

Anyone can tell me about this?

Thank you very much.

 

[Zapster]

I have seen this often accompanied with the appropriate spec break on the P&ID. This was done where the API flanges would mate up with ASME Class 900 or Class 1500 RTJ flanges.