AR052706A1 - STEEL TUBE WITHOUT INCREASED THICKNESS FOR PIPES WITH HIGH RESISTANCE AND INCREASED TENACITY AND PROCEDURE TO MANUFACTURE - Google Patents

Abstract

Translated fromSpanish

Un tubo de acero sin costura de espesor incrementado para tuberías con elevada resistencia y tenacidad incrementada, el cual tiene una composicion química en % en masa, constituida por los siguientes elementos: C0,03 a 0,8%, SI: no más de 0,25%, Mn:0,3 a 2,5%, AL: 0,001 a 0,10%, Cr: 0,02 a 1,0%, Ni: 0,02 a1.0%, Mo0,02 a 1,2%, Ti: 0,004 a 0,010%, N: 0,002 a 0,008% y 0,0002 a 0,005%, en total de al menos un elemento elegido entre Ca, Mg y tierras raras y siendo el resto Fe e impurezas, incluyendo opcionalmente V: 0 a 0,08%Nb:0 a 0,5% o Cu: 0 a 1,0%, y siendo P y S entre las impurezas no mayor que 0,05% y no mayor que 0,005% respectivamente. También puede contener 0,0003 a 0,01% de boro. El procedimiento de fabricacion del mismo se caracteriza por velocidad de enfriamiento, condicion de calentamiento para perforacion y tratamiento térmico después de la fabricacion del tubo. En donde una vez formado el tocho por colada continua con la composicion indicada, se utilizan velocidades no menores a 6 degree C/minuto para el enfriamiento, velocidades no mayores a 15 degree C/minuto para el calentamiento hasta una temperatura entre 1150 y 1280 degree C y velocidades medias no menor de 8 degree C/minuto para el enfriamiento forzado hasta una temperatura no mayor de 100 degree C del tubo obtenido, realizándose el revenido entre 500 y 690 degree C.A seamless steel tube of increased thickness for pipes with high strength and increased toughness, which has a chemical composition in mass%, consisting of the following elements: C0.03 to 0.8%, SI: no more than 0 , 25%, Mn: 0.3 to 2.5%, AL: 0.001 to 0.10%, Cr: 0.02 to 1.0%, Ni: 0.02 to 1.0%, Mo0.02 to 1 , 2%, Ti: 0.004 to 0.010%, N: 0.002 to 0.008% and 0.0002 to 0.005%, in total at least one element chosen from Ca, Mg and rare earths and the rest being Fe and impurities, including optionally V: 0 to 0.08% Nb: 0 to 0.5% or Cu: 0 to 1.0%, and P and S being between impurities not greater than 0.05% and not greater than 0.005% respectively. It can also contain 0.0003 to 0.01% boron. The manufacturing process thereof is characterized by cooling rate, heating condition for drilling and heat treatment after tube manufacturing. Where once the billet is formed by continuous casting with the indicated composition, speeds not less than 6 degree C / minute are used for cooling, speeds not greater than 15 degree C / minute for heating to a temperature between 1150 and 1280 degree C and average speeds of not less than 8 degree C / minute for forced cooling to a temperature not exceeding 100 degree C of the tube obtained, the tempering being performed between 500 and 690 degree C.