Normalizing type high-strength pressure vessel steel and manufacturing method thereof

Abstract

The invention provides normalizing type high-strength pressure vessel steel, which comprises the following chemical components in percentage by weight: 0.12 to 0.18 percent of C, 0.15 to 0.40 percent of Si, 1.20 to 1.70 percent of Mn, less than or equal to 0.020 percent of P, less than or equal to 0.015 percent of S, 0.10 to 0.40 percent of Ni, 0.01 to 0.05 percent of Nb and 0.01 to 0.03 percent of Ti, 0.015 to 0.050 percent of Als, one or both of less than or equal to 0.20 percent of V and less than or equal to 0.70 percent of Cu and the balance of Fe and inevitable impurities. In the normalizing type high-strength pressure vessel steel, the specification of the steel is controlled by utilizing a single-rolling process of a steel plate, and the uniform tissue of ferrite and pearlite is obtained by adopting normalizing heat treatment; and in the process of rolling and heat treatment, the sufficient strength and good impact properties are obtained by utilizing the effects of fine-grain strengthening, precipitation strengthening and solid solution strengthening of micro-alloying elements such as the Nb, the V, the Ti and the like. In addition, the normalizing type high-strength pressure vessel steel achieves the excellent welding performance by controlling carbon equivalent and can be welded by adopting methods of manual arc welding, hidden arc welding, gas shielded welding, electroslag welding or tungsten electrode inert gas shielded-arc welding and the like; and the normalizing type high-strength pressure vessel steel has the advantages of little used precious metals, easy control of the component of each element, simple process, low production cost and high efficiency.

Description

technical field [0001] The invention relates to the field of low-alloy pressure vessel steel manufacturing, in particular to a normalizing high-strength pressure vessel steel and a manufacturing method thereof. Background technique [0002] my country is a big country of oil production and consumption. With the development of economy and society, the growth of my country's oil consumption has exceeded the growth of crude oil production and reserves. The contradiction of oil shortage has become increasingly prominent. Finding an alternative product is undoubtedly a way to solve the problem. . Dimethyl ether, an environmentally friendly substance, has become increasingly obvious as an alternative energy source due to its good product performance and superior environmental protection performance. At present, several sets of 100,000-ton-scale devices have been built in China, and there is a tendency to develop to one million tons. Therefore, the large-scale DME reactor technolo...

AI Technical Summary

Problems solved by technology

But the C content in this patented steel is too high, and the welding performance is not good

At the same time, Cr and Mo precious metals are also added, which increases the production cost