Abstract: Disclosed herein are embodiments of a seamless quenched and tempered steel pipe which can have a wall thickness WT higher than or equal to 6 mm and lower than or equal to 35 mm. Some embodiments of the steel pipe can have a chemical composition comprising C, Mn, Si, Cr, Ni, Mo, Al, N, Ca, Nb, Ti, V, Zr, and Ta based on the composition weight, the remaining being iron and impurities. In some embodiments, wherein (V+Nb) content is lower than 0.07 wt %; defining a first parameter P1=(60×C)+Cr+[5×e(35×Mo/WT)]+50×(V+Nb), the chemical composition satisfies a first condition P1?14.5.

Abstract: Disclosed herein are embodiments of a seamless quenched and tempered steel pipe having a wall thickness (WT) higher than or equal to 35 mm and lower than or equal to 80 mm. Embodiments of the steel pipe can comprise C, Mn, Cr, Ni, Mo, Al, Ca, N, Nb, Ti, Zr, and Ta. Further, for some embodiments of the steel pipe wherein, defining a first parameter P1=50×C+Cr+10×Mo+70×V, the chemical composition can satisfy a first condition P1?8.0.

Abstract: Low-alloy steels and methods of manufacturing pipes having a wall thickness greater than or equal to about 8 mm and less than or equal to about 35 mm therefrom are provided. In one embodiment, a steel composition is processed that yields an average prior austenite grain size greater than about 15 or 20 ?m and smaller than about 100 ?m. A quenching sequence has been determined that yields a microstructure of greater than or equal to about 60% martensite by volume, and less than or equal to about 40% by volume lower bainite, without substantial formation of ferrite, upper bainite, or granular bainite. The yield strength of the quenched and tempered pipes may be greater than about 70 ksi, 80 ksi, or 90 ksi. The quenched and tempered pipes are suitable for 70 ksi, 80 ksi, and 90 ksi grades and resistant to sulfide stress corrosion cracking.

Abstract: A tubular article can be formed from high temperature steam oxidation resistant and high temperature creep resistant alloy steel. The steel can include a chemical composition that include Fe, C, Si, Mn, Ni, Cr, Cu, Ti, Nb, Mo, and N, and optionally other elements. The steel alloy can include 0.06 to 0.15 wt % C, 0.1 to 0.5 wt % Si, 0.2 to 0.6 wt %, 0.05 to 0.4 wt % Ni, 4.5 to 6.0 wt % Cr, 1.0 to 2.0 wt % Cu, 0.04 to 0.08 wt % Ti, 0.01 to 0.06 wt % Nb, 0.45 to 1.2 wt % Mo, and 0.008 to 0.05 wt % N, up to 0.01 wt % of optional element Al, up to 0.01 wt % of optional element Zr, up to 3.0 wt % of optional element Co, up to 0.07 wt % of optional element V, up to 3.0 wt % of optional element W, up to 0.015 wt % of optional element P, up to 0.003 wt % of optional element S, up to 0.1 wt % of optional element Ca, up to 0.1 wt % of optional element Ta, up to 0.1 wt % of optional element Mg, up to 0.1 wt % of optional element Se, up to 0.1 wt % of optional element Te, up to 0.1 wt % of optional element B, up to 0.

Abstract: Disclosed herein are embodiments of a seamless quenched and tempered steel pipe which can have a wall thickness WT higher than or equal to 6 mm and lower than or equal to 35 mm. Some embodiments of the steel pipe can have a chemical composition comprising C, Mn, Si, Cr, Ni, Mo, Al, N, Ca, Nb, Ti, V, Zr, and Ta based on the composition weight, the remaining being iron and impurities. In some embodiments, wherein (V+Nb) content is lower than 0.07 wt %; defining a first parameter P1=(60×C)+Cr+[5×e(35×Mo/WT)]+50×(V+Nb), the chemical composition satisfies a first condition P1?14.5.

Abstract: Disclosed herein are embodiments of a seamless quenched and tempered steel pipe having a wall thickness (WT) higher than or equal to 35 mm and lower than or equal to 80 mm. Embodiments of the steel pipe can comprise C, Mn, Cr, Ni, Mo, Al, Ca, N, Nb, Ti, Zr, and Ta. Further, for some embodiments of the steel pipe wherein, defining a first parameter P1=50×C+Cr+10×Mo+70×V, the chemical composition can satisfy a first condition P1?8.0.

Abstract: Embodiments of the present disclosure comprise carbon steels and methods of manufacturing thick walled pipes (wall thickness greater than or equal to about 35 mm) there from. In one embodiment, a steel composition is processed that yields an average prior austenite grain size greater than about 15 or 20 ?m and smaller than about 100 ?m. Using this composition, a quenching sequence is provided that yields a microstructure of greater than or equal to about 50% by volume, and less than or equal to about 50% by volume, lower bainite, without substantial ferrite, upper bainite, or granular bainite. After quenching, pipes may be tempered. The quenched and tempered pipes may exhibit yield strengths greater than about 450 MPa (65 ksi) or 485 (70 ksi). Mechanical property measurements find the quenched and tempered pipes suitable for 450 MPa grade and 485 MPa grade, and resistance to sulfide stress corrosion cracking.

Abstract: Embodiments of the present disclosure comprise carbon steels and methods of manufacturing thick walled pipes (wall thickness greater than or equal to about 35 mm) there from. In one embodiment, a steel composition is processed that yields an average prior austenite grain size greater than about 15 or 20 ?m and smaller than about 100 ?m. Using this composition, a quenching sequence is provided that yields a microstructure of greater than or equal to about 50% by volume, and less than or equal to about 50% by volume, lower bainite, without substantial ferrite, upper bainite, or granular bainite. After quenching, pipes may be tempered. The quenched and tempered pipes may exhibit yield strengths greater than about 450 MPa (65 ksi) or 485 (70 ksi). Mechanical property measurements find the quenched and tempered pipes suitable for 450 MPa grade and 485 MPa grade, and resistance to sulfide stress corrosion cracking.

Abstract: Low-alloy steels and methods of manufacturing pipes having a wall thickness greater than or equal to about 8 mm and less than or equal to about 35 mm therefrom are provided. In one embodiment, a steel composition is processed that yields an average prior austenite grain size greater than about 15 or 20 ?m and smaller than about 100 ?m. A quenching sequence has been determined that yields a microstructure of greater than or equal to about 60% martensite by volume, and less than or equal to about 40% by volume lower bainite, without substantial formation of ferrite, upper bainite, or granular bainite. The yield strength of the quenched and tempered pipes may be greater than about 70 ksi, 80 ksi, or 90 ksi. The quenched and tempered pipes are suitable for 70 ksi, 80 ksi, and 90 ksi grades and resistant to sulfide stress corrosion cracking.

Abstract: A low-alloy steel containing, by weight percent, C 0.03-0.13%, Mn 0.90-1.80%, Si?0.40%, P?0.020%, S?0.005%, Ni 0.10-1.00%, Cr 0.20-1.20%, Mo 0.15-0.80%, Ca?0.040%, V?0.10%, Nb?0.040%, Ti?0.020% and N?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?0.40%, P?0.020%, S?0.005%, Ni 0.10-1.00%, Cr 0.20-1.20%, Mo 0.15-0.80%, Ca?0.040%, V??0.10%, Nb?0.040%, Ti?0.020% and N?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).

Abstract: A low-alloy steel containing, by weight percent, C 0.03-0.13%, Mn 0.90-1.80%, Si?0.40%, P?0.020%, S?0.005%, Ni 0.10-1.00%, Cr 0.20-1.20%, Mo 0.15-0.80%, Ca?0.040%, V?0.10%, Nb?0.040%, Ti?0.020% and N?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?0.40%, P?0.020%, S?0.005%, Ni 0.10-1.00%, Cr 0.20-1.20%, Mo 0.15-0.80%, Ca?0.040%, V??0.10%, Nb?0.040%, Ti?0.020% and N?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).

Abstract: A process for the production of low carbon steel strips having a good combination of strength an formability, as cast, and a good weldability after the pickling by usual processes, comprising the following steps: casting, in a twin rolls continuous casting machine (1) comprising pinch rolls (3), a strip with a thickness comprised between 1 and 8 mm, having the following composition as weight percentage of the total weight: C 0.02-0.10; Mn 0.1-0.6; Si 0.02-0.35; Al 0.01-0.05; S<0.015; P<0.02; Cr 0.05-0.35; Ni 0.05-0.3; N 0.003-0.012; and, optionally, Ti<0.03; V<0.10; Nb<0.035, the remaining part being substantially Fe; cooling the strip in the area comprised between the casting-rolls and the pinch rolls (3); hot deforming the strip cast through said pinch rolls (3) at a temperature comprised between 1000 and 1300° C. until reaching a thickness reduction less than 15%, in order to encourage the closing of the shrinkage porosites; cooling the strip at a speed comprised between 5 and 80° C.