Enter the future corrosion allowance (the projected future metal loss) away from the region of local metal loss. The future corrosion allowance should be based on past inspection information or corrosion rate data relative to the component material in a similar environment. Corrosion rate data can be obtained from API Publication 581 or other sources (see paragraph 2C.2.7). The FCA is calculated by multiplying the anticipated corrosion rate by the future service period considering inspection interval requirements of the applicable inspection code.
Note for Part 6 – Per paragraph 6.2.7, the future corrosion allowance (FCA) shall be based on the projected future metal loss in the pitting region. The FCA is not applied to the depth or diameter of the pits.