A thermal flow-driven elastic cone parking sealing device for nuclear main pumps

Abstract

The invention relates to a heat flow driving type elastic cone parking sealing device for a nuclear main pump. The heat flow driving type elastic cone parking sealing device comprises a sealing support and an elastic cone, wherein a triangular heat expansion layer is welded on the elastic cone; a rectangular heat expansion layer is welded on the sealing support; the elastic cone is sleeved on a main shaft, and a sealing gap is formed between the elastic cone and the sealing support; the elastic cone and the main shaft are in interference fit; a sealing ring is arranged between the elastic cone and the main shaft; when primary seal of the nuclear main pump is in failure, under the effect of a fluid force, the elastic cone is pressed to the sealing support; moreover, under the heat effect of a hot flow, the triangular expansion layer is expanded by heat, and the elastic cone is further compressed; the rectangular expansion layer on the sealing support is expanded by heat, the elastic cone is compressed radially; under the fluid force and the pressing forces of the triangular expansion layer and the rectangular expansion layer, the top end of the elastic cone is deformed, and surface contact of the elastic cone and the sealing support is realized, thus a flow leakage passage is blocked, and leakage of radioactive sealing fluid is prevented; the device changes the driving manner of parking sealing work, an external air source is not required, and the device has nonmotility.

Description

technical field [0001] The invention belongs to the technical field of nuclear main pumps, and in particular relates to a thermal flow-driven elastic cone parking sealing device for nuclear main pumps. Background technique [0002] In severe accidents, in order to ensure the leakage of radioactive fluid in the nuclear main pump of the reactor, the nuclear main pump needs to be equipped with a shutdown seal. The existing nuclear main pump parking seal is driven by high-pressure nitrogen gas. The high-pressure gas generates pressure on the sealing piston, which pushes the sealing piston to move toward the stepped shaft and is pressed against the stepped shaft. The sealing ring on the contact surface realizes the sealing of the radioactive fluid. [0003] Inadequacies of the existing technology and design: the shutdown sealing device for the nuclear main pump does not have passive characteristics, and is dependent on the external high-pressure nitrogen gas source, and the relia...

AI Technical Summary

Problems solved by technology

[0003] Inadequacies of the existing technology and design: the shutdown sealing device for the nuclear main pump does not have passive characteristics, is dependent on the external high-pressure nitrogen source, and is not reliable enough. If the high-pressure gas source is lost at the same time in a serious accident, the shutdown seal Impossible to operate, the sealing function fails, and a large amount of radioactive fluid leaks

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