A device and method for dismounting and mounting a reactor pressure vessel main nut

By designing a special disassembly and assembly device for the main nut of a reactor pressure vessel, and utilizing the cooperation of a locking ring and a lifting hook, the safe and efficient disassembly and assembly of the main nut is achieved, solving the problems of low efficiency and safety risks in the existing technology.

CN117444600BActive Publication Date: 2026-06-09SANMEN NUCLEAR POWER CO LTD
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Patent Information

Application Number
CN202311367626.1
Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
Filing Date
2023-10-20
Publication Date
2026-06-09
Estimated Expiration
2043-10-20

AI Technical Summary

Technical Problem

In the existing technology, the disassembly and installation of the main nut of the reactor pressure vessel is inefficient and poses risks of thread damage and personnel injury. The lack of special tools also makes operation inconvenient.

Method used

Design a device including a support sleeve, a locking ring, a lifting hook, and an insert plate. With the help of a crane, the main nut can be safely disassembled and assembled. The locking ring and the lifting hook work together to ensure stable gripping and rotation, and prevent accidental opening or closing.

Benefits of technology

It improves the efficiency of main nut assembly and disassembly, reduces thread damage and personnel injury risk, is easy to operate and safe and reliable, and reduces the difficulty of operation.

✦ Generated by Eureka AI based on patent content.

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Abstract

This invention belongs to the technical field of nuclear power plant reactor pressure vessel maintenance, specifically relating to a device and method for disassembling and assembling the main nut of a reactor pressure vessel. The device includes: a support sleeve, a locking ring, inserts, and lifting hooks. Several lifting hooks are evenly connected along the lower outer periphery of the support sleeve, and these hooks can open and close relative to the support sleeve. The bottom of each lifting hook has an inwardly facing protrusion for hooking the main nut or a main nut washer. Several inserts are evenly connected to the bottom of the support sleeve, the shape of which matches the U-shaped groove on the main nut, for applying torque to the main nut during rotation. The locking ring is sleeved around the outer periphery of the lifting hooks for fixing them. This invention has a simple structure and is easy to operate, effectively improving work efficiency while ensuring that the lifting hooks will not open or close accidentally during operation, greatly reducing operational risks.
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Citation Information

Patent Citations

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