ABSTRACT
The elastic limit of the material is reached, which means that the material now does not return precisely to its original dimensions. The material of choice for the construction of an offshore structure is usually carbon steel (also referred to as carbon-manganese steel). This is a generic term covering a multitude of materials of various chemical compositions, microstructures, thermal histories and mechanical properties. Where practicable subsea equipment is also fabricated in medium-strength carbon steel, although the bolting is usually a high-strength low-alloy steel. However, mechanical requirements, or the need to resist the corrosivity of a contained fluid, frequently force the material selection towards corrosion-resistant alloys. However, since Cathodic Protection (CP) provides an enhancement on the in-air performance, the mechanism is evidently more nuanced. Hooper and Hartt posited that the benefit of CP is intimately linked to the role of calcareous deposits.
