Tenaris Connections Limited

Alfonso Izquierdo Garcia

Toshihiko Fukui

Gustavo López Turconi

Ettore Anelli

Héctor Manuel Quintanilla Carmona

Marco Mario Tivelli

Andrea Di Schino

Gustavo Lopez Turconi

Embodiments of the present application are directed towards steel compositions that provide improved properties under corrosive environments. Embodiments also relate to protection on the surface of the steel, reducing the permeation of hydrogen. Good process control, in terms of heat treatment working window and resistance to surface oxidation at rolling temperature, are further provided.

Steels for sour service environments

A low-alloy steel containing, by weight percent, C 0.03-0.13%, Mn 0.90-1.80%, Si&#x2266;0.40%, P&#x2266;0.020%, S&#x2266;0.005%, Ni 0.10-1.00%, Cr 0.20-1.20%, Mo 0.15-0.80%, Ca&#x2266;0.040%, V&#x2266;0.10%, Nb&#x2266;0.040%, Ti&#x2266;0.020% and N&#x2266;0.011% for making high-strength, weldable steel seamless pipe, characterized in that the microstructure of the alloy steel is a mixture of bainite and martensite and the yield stress is at least 621 MPa (90 Ksi). It is a second object of the present invention to provide a high-strength, weldable steel seamless pipe, comprising an alloy steel containing, by weight percent, C 0.03-0.13%, Mn 0.90-1.80%, Si&#x2266;0.40%, P&#x2266;0.020%, S&#x2266;0.005%, Ni 0.10-1.00%, Cr 0.20-1.20%, Mo 0.15-0.80%, Ca&#x2266;0.040%, V&#x2266;&#x2266;0.10%, Nb&#x2266;0.040%, Ti&#x2266;0.020% and N&#x2266;0.011% also characterized in that the microstructure of the alloy steel is predominantly martensite and the yield stress is at least 690 MPa (100 ksi).

High-strength steel for seamless, weldable steel pipes

Growing community of inventors

Veracruz, Mexico

Alfonso Izquierdo Garcia