Method for determining expansion process parameters of tube and tube plate of AP1000 nuclear evaporator

Abstract

The invention relates to a method for determining the expansion process parameters of a tube and a tube plate of an AP1000 nuclear evaporator, which comprises the followings steps: determining the minimum pull-off strength index value of an expanded joint of the tube and the tube plate and the thinning rate limited value of the tube subjected to expansion; carrying out three-dimensional finite element calculation so as to obtain the relationship between the expansion pressure and the thinning rate of the tube, the relationship between the expansion pressure and the pull-off force of the joint, and the relationship between the expansion pressure and the interfacial residual contact pressure of the tube and the tube plate when different initial gaps are formed between the tube and the tube plate; determining the yield strengths of materials of the tube plate and the tube at room temperature; determining the initial gap value between the tube and the tube plate; determining the minimum expansion pressure value corresponding to the initial gap value when the pull-off force is equal to the minimum pull-off strength index value, and the maximum expansion pressure value corresponding to the thinning rate limited value of the tube subjected to expansion; selecting an expansion pressure from an interval between the mid-value of the minimum and maximum expansion pressure values and the maximum expansion pressure so as to carry out expansion and pull-off tests, and determining the optimal expansion pressure value corresponding to the initial gap value and the pull-off force corresponding to the optimal expansion pressure; and determining the interfacial residual contact pressure value corresponding to the initial gap value and the optimal expansion pressure value.

Description

technical field [0001] The invention belongs to the technical field of nuclear power equipment manufacturing, and specifically relates to a method for determining the process parameters of the expansion joint of the tube and tube plate of the AP1000 third-generation nuclear power evaporator, which provides a calculation and analysis method for the expansion joint process of the tube and the tube plate of the AP1000 nuclear power evaporator. Background technique [0002] The connection of nuclear power evaporator tube / tube sheet generally adopts the process method of strength expansion and sealing welding. The failure of the strength of the expansion joint will lead to the leakage of the radioactive and corrosive heat transfer medium on the primary side, which will have a great impact on the safe operation of the equipment and the environment. Therefore, the quality of the expansion joint of the tube / tube sheet is the key to ensuring the normal operation of the nuclear power e...

AI Technical Summary

Problems solved by technology

The structure, material and tube hole arrangement of the advanced third-generation AP1000 nuclear power evaporator tubes / tube sheets currently under construction are different from those of the second generation, and the second-generation expansion joint process parameters determined based on tests and experience cannot be used for the third-generation generation

According to literature and patent searches, there is no method to determine the process parameters of AP1000 third-generation nuclear power evaporator tube / tubesheet expansion joint at home and abroad.

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