Combination fluid dynamic pressure groove mechanical seal ring capable of automatically discharging particles

Abstract

The invention relates to a combination fluid dynamic pressure groove mechanical seal ring structure capable of automatically discharging particles. The combination fluid dynamic pressure groove mechanical seal ring structure is characterized in that on a sealing moving ring or a static ring, a circulation outer circle arc groove and a pumping groove which are symmetrically arranged about the rotation center are sequentially arranged from the high-pressure side and the low-pressure side. The outer circle arc groove is formed in the upper portion (high-pressure side) of the end face and the pumping groove is formed in the lower portion (low-pressure side) of the end face. The arc groove and the pumping groove are communicated at the contact place so as to ensure that the particles entering the pumping groove enter the arc groove by means of the pumping effect and return to a sealing cavity through medium circulation. Meanwhile, by means of the dynamic pressure effect and the pumping effect of the arc groove and the pumping groove, the bearing capacity and the low leakage amount of a liquid film are ensured. Thus, the good sealing capacity and the automatic particle discharging capacity of the combination fluid dynamic pressure groove mechanical seal can be achieved. The dynamic pressure groove is prevented from being blocked and abrasion of the sealing end face is relieved. The seal ring can be applied to working conditions including solid particle media.

Description

technical field [0001] The present invention relates to fluid mechanical seal technology and fluid dynamic pressure lubrication theory, specifically refers to a mechanical seal liquid film bearing capacity and low leakage as the premise, automatic excretion of micro particles entering the sealing end face, preventing the pumping groove from clogging and losing the pump. increases delivery capacity, minimizes leakage, reduces face wear and extends mechanical seal life. Background technique [0002] In modern industrial applications, in order to meet the strict requirements of zero leakage, low wear and long service life of mechanical seals in aerospace, nuclear power, petrochemical and other industries, surface modification sealing technologies (dry gas sealing technology, upstream pumping mechanical Sealing technology, thermal fluid dynamic sealing technology, etc.), multi-face sealing technology, monitoring sealing technology, combined sealing technology, etc. Its ultimate...

AI Technical Summary

Problems solved by technology

These sealing technologies can achieve good results when transporting some impurities-free media, but in the case of transporting petroleum and chemical industries containing particles and impurities, solid particles are often sucked between the sealing end faces due to this type of mechanical seal. If it cannot be removed in time, the micro-molding of the sealing end face will become blocked and fail to play the role of dynamic pressure sealing application. At the same time, abrasive wear will occur, resulting in seal failure and serious accidents.

[0003] In recent years, the main solution to problems such as mechanical seal particle wear and failure is: by adding auxiliary systems, adopting measures such as filtration, flushing, separation, and isolation, but this often leads to higher costs and more complicated structures; The outer cover is covered with an isolation sleeve to avoid direct contact between the elastic element and the medium, but the stress on the sealing end face is changed, and the cost is also high

Aiming at the problem of mechanical seal end face inhalation of solid particles and wear, some researchers have also proposed several end face modification designs, such as: Chinese patent 2534429Y discloses a double-row co-directional hydrodynamic pressure tank upstream pumping mechanical seal, which has better sealing ability and anti-solid particles, but once the particles enter the pumping groove and cause blockage, the mechanical seal will lose its dynamic pressure effect and pumping effect, resulting in seal failure; Chinese patent 101701585A discloses a two-way self-upstream pumping mechanical seal ring, which simplifies the sealing structure and prolongs the service life of the seal, but after the particles are sucked into the end face, there is no mechanism for removing impurities, and the clogging problem still exists; type of mechanical seal ring structure, but it has not been verified whether the modified end face structure still has better end face opening performance and sealing ability

EP0564153A1 discloses a non-contact mechanical seal with double-row spiral grooves, which has better starting performance and solid particle prevention ability, but its sealing ability is low and its application range is limited

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