A method for taking out a heat transfer tube of a steam generator

Abstract

The invention belongs to the technical field of nuclear power maintenance, and in particular relates to a method for taking out heat transfer tubes of steam generators. After obtaining the specific position of the heat transfer tube, cut the heat transfer tube by cutting the tube inwardly, and then use metal heating equipment to form a helical or straight heating track on the inner wall of the heat transfer tube to reduce the tube diameter, and then cut it from the primary side of the tube sheet its unplugged. The beneficial effect is that the heat transfer tube of the in-service (or decommissioned) steam generator can be removed without damaging (cutting) the steam generator shell, and the in-service steam generator can still be used after the tube is removed . The invention utilizes the principle of electric spark machining, without complex transmission mechanism, can realize cutting the heat transfer tube from the inside to the outside at an indeterminate height, and can overcome the difficulty of cutting the heat transfer tube in a special environment; use argon arc welding to melt The principle of metal removes the expansion force of the heat transfer tube, and can complete the radial shrinkage of the heat transfer tube, so as to realize the peeling of the heat transfer tube and the tube hole of the tube sheet.

Description

technical field [0001] The invention belongs to the technical field of nuclear power maintenance, and in particular relates to a method for taking out heat transfer tubes of steam generators. Background technique [0002] The heat transfer tube of the steam generator of the nuclear power plant is a key component in the steam generator. After several cycles of operation, it may be degraded due to corrosion, micro-shock or impact of foreign objects. It is necessary to take out a section of degraded tube and conduct eddy current inspection, aging or other evaluations to verify that the design of the original heat transfer tube can meet the requirements of use. At the same time, this has certain guiding significance for the design and research of new heat transfer tubes, and is also an important means to promote the renewal of heat transfer tube materials and performance improvements. In order to better realize the research purpose, the heat transfer tubes in a specific area of...

AI Technical Summary

Problems solved by technology

[0006] (3) After the heat transfer tube is taken out, the hole in the tube plate will cause the primary and secondary side coolants to communicate with each other during the operation of the steam generator, causing a radioactive leakage accident

[0007] (4) After taking out a section of the heat transfer tube, the remaining section of the heat transfer tube will vibrate when the steam generator is running, which is prone to risk

Images