Max Avail Corr Allow for Carbon Steel Flanges and Fittings

[Angsi]

Can someone please advise me, based on their past calc/experience if carbon steel flanges such as A105N and fittings to A234 WPB, what will be minimum available thickness for corrosion allowance after deducting that required for pressure thickness? For a start I know that it has to be above 3mm but how much more?

I am trying to determine if there is a chance of getting 6mm corrosion allowance from these flanges and fittings.

Thanks in advance.

 

[SJones]

The answer to that question will have to be developed between the system operator and the flange/fitting supplier based on the system operating restrictions imposed by the operator and the manufacturing designs of the supplier.

Steve Jones
Materials & Corrosion Engineer

http://www.pdo.co.om/pdo/

 

[stanweld]

The dimensions of flanges and fittings are most often governed by Standards; e.g. ASME B16.5, B16.9, B16.11 etc. or by the purchaser. Flange ratings provide the maximum allowable pressure at temperature for design. The minimum thickness required for design is based on other Codes; e.g. ASME B31.1, B31.3, ASME Section I, VIII, etc. After calculating minimum thickness at the design pressure and temperature, any excess thickness is available for corrosion allowance.