65results about How to "Guaranteed Low Temperature Toughness" patented technology

The invention discloses low-temperature ductility 1.5Ni steel and a manufacturing method thereof, wherein the low-temperature ductility 1.5Ni steel comprises the chemical components according to percentages by weight of 0.02-0.10 percent of C, 0.22-0.30 percent of Si, 1.00-1.50 percent of Mn, less than or equal to 0.08 percent of V, 1.20-1.60 percent of Ni, less than or equal to 0.005 percent of S, less than or equal to 0.010 percent of P, less than or equal to 0.03 percent of Nb, less than or equal to 0.04 percent of Ti, less than or equal to 0.04 percent of Al, 0.002-0.005 percent of N and the rest of Fe and unavoidable impurities. The manufacturing method comprises the following steps of smelting and casting into a casting blank, heating the casting blank, controlled rolling and heat treatment. In the invention, after the micro alloy steel finishes the controlled rolling, a high-strength low-temperature pressure vessel steel plate which has yield strength of more than 400MPa, tensile strength of more than 500MPa and satisfies the low-temperature impact ductility requirement of 100 DEG C below is produced through adopting a thermal refining method. The invention is suitable for manufacturing vessels, such as a low-temperature pressure vessel, a liquefied natural gas storage tank, a liquefied petroleum gas storage tank, a petrochemical storage tank, and the like.

The invention relates to an ultrahigh-strength structural steel board for ocean engineering and a production method thereof, belonging to the technical field of ultrahigh-strength steel. A board blank comprises the following components: 0.05-0.13% of C, 0.1-0.4% of Si, 0.7-1.7% of Mn, 0.01-0.04% of Alt, 0.02-0.05% of Nb, 0-0.05% of V, 0.008-0.02% of Ti, 0-0.6% of Cr, 0.2-0.4% of Mo, 0.15-0.8% of Ni, 0-0.5% of Cu, 0-0.0011% of B, less than 0.01% of P, less than 0.005% of S, less than 0.0010% of O, less than 0.005% of N, less than 0.00015% of H, and the balance of Fe and inevitable impurities, wherein Nb+V+Ti is not more than 0.12%. Aiming at different thickness standards, different chemical component as well as rolling and heat treatment process parameters are adopted. The production process comprises the steps of molten iron desulfurization, converter top and bottom blowing, vacuum treatment, continuous casting, controlled rolling and controlled cooling, quenching and tempering. The steel board has the advantages that: the production cost is lower, and the comprehensive mechanical properties can meet the requirements of the steel for the ocean engineering for various mechanical properties.