METHOD FOR DESIGNING UNDERWATER EQUIPMENT CONFIRMED BY HYDROGEN CALLED BY HYDROGEN UNDER STRESS

摘要

1. A method for evaluating hydrogen induced stress cracking associated with an underwater pipeline system, comprising: (a) determining a one-dimensional model for an element of said underwater pipeline system; (b) performing a one-dimensional analysis for said element using said one-dimensional model and a plurality of operating conditions for identifying at least one point associated with hydrogen induced stress cracking for said element; (c) applying at least one transform function referring to said at least one point to convert said at least one point from a one-dimensional representation into an estimate of local voltage; and (d) the derivation of said local stress estimate. 2. The method of claim 1, further comprising: (a) analyzing said local voltage estimate for a first predetermined match; and (b) if said local stress estimate is not appropriate, then determining and performing a three-dimensional submodel for said element and analyzing the output of said three-dimensional submodel for compliance with a second predetermined suitability condition. 3. The method of claim 2, wherein said first predetermined match is a linear estimate of hydrogen induced stress cracking. The method of claim 2 or 3, wherein said output from said three-dimensional submodel is an estimate of local voltage. The method according to claim 2 or 3, wherein said second predetermined correspondence is a correspondence of a non-linear estimate of the induced hydrogen