Abstract

CUMINO, G. et al. Supermartensitic 13 %Cr large diameter seamless pipes: Mechanical corrosion and weldability properties. Lat. Am. appl. res. [online]. 2002, vol.32, n.3, pp. 215-219. ISSN 0327-0793.

The demand for weldable 13%Cr pipes with outside diameter such as 18", 20" and 24" has increased greatly. Considering such a requirement, Dalmine and NKK have developed a new production route for OD 20" pipes. Girth welded joints (GTAW) were produced. The mechanical properties of both base material and welded joints meet the target requirements. Corrosion qualification was aimed to determine the Sulfide Stress Cracking (SSC) resistance in slightly sour oil wells. Influence of chloride content (NaCl 5÷25%), H2S partial pressure (1÷10 kPa) and pH (3.5÷5), was assessed. CO2 corrosion resistance was verified with static exposure tests at medium/high pressure of CO2, high chloride (25% NaCl) and temperature up to 150°C.

Keywords : 13%Cr steels; flowline; Gas Tungsten Arc Welding (GTAW); toughness; Sulfide Stress Corrosion (SSC).