Heavy Wall UOE SAWL Pipes for Ultra Deep Water and Sour Service Application
Proceedings Publication Date
The demand for oil and gas exploration leads to new challenges for engineering and materials development of pipelines as the requirement of compliance with demanding requirements for hostile environments such as sour corrosion resistance, high strength, high toughness and heavy wall thickness to resist the external collapse pressure and good weldability for field installation. The reserves of Pre-Salt in Brazilian coast is an example of such challenge, since it combines fields that are located at approximately 250 km off the coast, up to 3,000 meters deep water and corrosive environments. Pipeline manufacturing excellence starts with material selection. Desired steel properties can be achieved by high end technologies in steelmaking. The UOE-SAWL process for pipe production enables the transportation of large amounts of oil and gas using large diameter pipes in safe conditions. In order to attend the main Brazilian projects, special requirements including DNV-OS-F101 have to be fulfilled by the pipe manufactures. This paper presents the evaluation of mechanical properties and corrosive resistance of OD 24 in x WT 38.1 mm grade DNV 450 SFD produced according to DNV-OS-F101, supplementary requirements and corrosive tests carried out in conformance with NACE MR0175 and NACE TM0177. The mechanical properties obtained showed compliance with the necessary standards. Material toughness obtained from Charpy V-Notch tests of Base Metal, Heat Affect Zone and Weld, DWTT, CTOD show good results. Sour corrosion tests results obtained show satisfactory results. These results shows that the pipes are fit for the challenges of the new exploration fields in Brazil and other high demanding fields with hostile environments.