Steel plate for hardening and tempering type low temperature pressure vessel and method for producing steel plate

Abstract

The invention discloses a steel plate for a hardening and tempering type low temperature pressure vessel with ultralimit thickness, low crack sensitivity and high strength and a method for producing the steel plate. The steel plate comprises the following chemical constituents according to percent by weight: 0.065-0.085% of C, 0.15-0.25% of Si, 1.30-1.50% of Mn, 0.40-0.45% of Ni, 0.15-0.25% of Cr, 0.20-0.25% of Mo, 0.035-0.045% of V, 0.030-0.045% of of Nb, 0.025-0.03% of Ti, 0.020-0.05% of Alt, 0.015% of P, 0.005% of S and the balance of Fe; and the method for preparing the steel plate comprises the steps that molten steel is smelted according to set constituents, the molten steel is cast into a casting blank, two stages of rolling, i.e. rough rolling and fine rolling are carried out after the heating, after quick cooling, a hardening and tempering technology is carried out for thermal treatment, matching of excellent strength, plasticity, cold bending and shock resistance can be achieved, and the requirement of the steel for the low temperature pressure vessel is satisfied.

Description

technical field [0001] The invention belongs to the field of metallurgy, and in particular relates to a steel plate for a pressure vessel, in particular to a steel plate for a low-crack sensitivity, high-strength quenched and tempered low-temperature pressure vessel with an ultra-limit thickness (60 mm) and a preparation method thereof. Background technique [0002] Quenched and tempered high-strength steel plates for pressure vessels are widely used in the hydropower industry and spherical tank manufacturing industry because of their low welding crack sensitivity index (Crack-Free), also referred to as CF steel. With the development of pressure vessel equipment in the direction of high parameters and large-scale, not only the problem of large-scale equipment needs to be considered, but also the safety problem must be solved first, that is, the CF steel used for hydropower and spherical tanks must ensure the low-temperature performance requirements, such as The design temper...

AI Technical Summary

Problems solved by technology

Considering that in some special occasions, the steel plate is required to exceed the limit thickness stipulated in the new national standard, even reaching 60mm, and at the same time, it is also required to ensure the mechanical and process performance requirements in the new national standard. For manufacturing companies, no similar products have been developed. precedent, which brings certain difficulties to manufacturing enterprises

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