A kind of 6mm thick nuclear power containment steel and its manufacturing method

Abstract

The invention discloses a 6mm-thick nuclear power containment steel and a manufacturing method thereof. The steel adopts a low C and Mn component series design, does not add additional alloy components, and takes into account the radiation effect while ensuring the stability of the yield strength. The optimization of the material shape of the billet in the manufacturing method realizes the effective control of the length of the rolled piece during the rolling process, and avoids the large temperature fluctuation caused by the excessive length of the rolled piece. The ultra-high temperature heating system is adopted to ensure that the billet obtains a higher temperature during rolling, and to ensure that the steel plate has a higher final rolling temperature after the rolling is completed. The control of the rolling process reduces the temperature drop during the process and ensures that the fluctuation of the temperature difference between the head and the tail of the rolled piece is small. The length of the rolled piece is optimized and the area with poor plate shape is cut off to ensure the uniformity of the performance of the sampling position. The yield strength of the 6mm nuclear power steel produced by the method is stable, and the obtained performance is excellent in strength and toughness matching, which fully meets the performance requirements. The qualified rate of production performance reaches 94%, which is fully suitable for industrial batch production.

Description

technical field [0001] The invention relates to a steel for nuclear power containment, in particular to a 6mm thick steel for nuclear power containment and a manufacturing method thereof. Background technique [0002] The reactor containment structure of a nuclear power plant is very important in the construction of a nuclear power plant, and it is called the last barrier of nuclear safety. The containment shell can be divided into three types according to the material: steel, reinforced concrete and prestressed concrete. The second-generation or second-generation improved nuclear power plants built in my country and the French-standard pressurized water reactor nuclear power plants mostly use reinforced concrete containment, that is, a reinforced concrete single-layer containment with a thin carbon steel lining. It consists of a shell and a hemispherical top. The representative steel types are mainly 20HR, P265GH, Q265HR, etc., and the strength level is the lower 265 level...

AI Technical Summary

Problems solved by technology

Since the upper and lower limits are less than 100MPa, the following problems often occur in the production process: 1. During the rolling process of thin gauge, the temperature drops rapidly, resulting in a large temperature difference between the head and tail of the rolled piece, and large performance fluctuations

2. In mass production, the requirement of yield strength ≥ 265MPa in the technical conditions can generally be met, but the average value is often less stable, and it is easy to exceed the upper limit, which leads to the change of the steel plate, resulting in an increase in production costs

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