Can someone point me to a temp/pressure rating chart or curve for API 6A 10M weld neck flanges 1

[10mm]

I am trying to determine the pressure ratings for a given temp(chart or curve) for API 6A flanges. I have found a unofficial chart, but cannot seem to find anything trustworthy. Hopefully this is posted in the correct category.

There is no situation so bad that you cant make it worse. Cmdr_Hadfield

 

[jmec87]

API 6A assumes that no de-rating is required for temperatures up to 250°F.

For temperatures above 250°F, see API TR 6AF1 "Technical Report on Temperature Derating of API Flanges Under Combination of Loading". It includes charts showing ratings for combined tension, bending, and pressure loading at 650°F and at least one lower temperature (I think 350°F).

 

[10mm]

I was trying to find out what the pressure rating is at 250F. It is currently in a 120F (10m rated for 10,000psi) design, but we were wanting to increase the temp to 250F. It sounds like we may be in good shape then. I will see what I can find in API TR 6AF1 to verify and document.
Thanks for the info.

There is no situation so bad that you cant make it worse. Cmdr_Hadfield

 

[jmec87]

You're welcome. If you want more information at 250°F, you can also look at API TR6AF2. It is focused on combined loading capacities of flanges but also evaluates "the effect of a temperature difference corresponding to 250 °F on the inside and 30 °F on the outside".

There is an informative abstract of API TR6AF2 at:

https://global.ihs.com/doc_detail.cfm?document_name=API TR 6AF2&item_s_key=00143114

The abstract includes the following statement: "The temperature difference of 250 °F internal and 30 °F external leads to increases in the load-carrying capacity of the flanges."