Fluid dynamic pressure type mechanical sealing face structure

Abstract

The invention relates to a fluid dynamic pressure type mechanical sealing face structure. Twelve grooves are formed in a sealing end face of a stationary ring, and a regular dodecagon can be formed by connecting the twelve grooves. The grooves are in mutual communication. The connection position of any two adjacent grooves communicates with the outer circumferential surface of the stationary ring. A rotating ring rotates along with a shaft connected with the rotating ring to produce a centrifugal effect, fluid in the grooves is driven to rotate, and therefore a liquid membrane is formed between a sealing end face of the rotating ring and the sealing end face of the stationary ring. The stationary ring and the rotating ring are made from a silicon carbide-graphite composite material, and machined with the reaction bonded silicon carbide and carbon technology. The fluid dynamic pressure type mechanical sealing face structure is suitable for a nuclear main pump, and a good sealing function in a high pressure and radioactivity working environment is achieved.

Description

technical field [0001] The invention belongs to the technical field of mechanical engineering, and relates to large and medium-sized machines using high-pressure, radioactive working medium and a fluid dynamic mechanical seal required for long life, in particular to a fluid dynamic mechanical sealing surface structure. Background technique [0002] Mechanical seals have widely replaced gland soft packing seals due to their low leakage and no need for routine maintenance. Among them, the hydrodynamic mechanical seal is designed with a special geometric structure on the sealing surface, and uses the relative rotation to generate the hydrodynamic effect by itself. [0003] The sealing surface of the hydrodynamic mechanical seal is composed of two sealing planes perpendicular to the axis of rotation. One of the sealing surface parts is installed on the other parts to keep it stationary, called "static ring", while the other is fixed on the shaft and Then rotate, called "moving ...

AI Technical Summary

Problems solved by technology

Among them, due to the small fluid dynamic pressure of micron-sized shallow grooves, it is easy to cause insufficient liquid film thickness under certain working conditions, resulting in dry grinding of the sealing surface.

The corrugated surface is difficult to process, and it is difficult to ensure that the peak of the oblique corrugated surface is equal to the theoretical surface due to processing errors

The mm-level groove-shaped sealing surface is simple in structure, easy to process, and has the widest range of applications. However, some structural designs have poor resistance to non-uniform force and thermal influence. The selected materials and manufacturing processes are not suitable, which may easily cause local deformation and liquid film. unstable

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