Innovative Duplex Stainless Steel UNS S83072: Enhanced Strength for Deep-Sea Umbilical Tubing

Paper ID: C2025-00036 ABSTRACT: Duplex stainless steels have long been the material of choice for umbilical tubing in the offshore industry due to their excellent combination of high strength and corrosion resistance. Alleima's new steel grade, UNS S83072, represents a significant advancement in this field, specifically engineered to meet the demanding requirements of deep-sea environments. This super duplex stainless steel offers enhanced mechanical properties along with excellent corrosion resistance, making it a cost efficient solution and an ideal candidate for deep-sea umbilical tubing.
UNS S83072 witha mechanical strength that is 10-15% higher than its predecessor, SAF 2507 (UNS S32750), allow for the production of thinner tube walls. This reduction in material thickness translates to lower overall weight without sacrificing performance. The alloy maintains excellent corrosion resistance, comparable to SAF 2507, making it suitable for prolonged exposure to chloride-containing environments such as seawater. Microstructural evaluations have confirmed that UNS S83072 exhibits a stable duplex (austenitic-ferritic) microstructure. A very low concentration of intermetallic phases, <0.5%, has been measured after multi pass welding of wall thicknesses >4 mm, ensuring long-term reliability.
In summary, UNS S83072 is designed to meet the evolving needs of the offshore industry, offering a reliable and technically superior solution for umbilical tubing.