Selection criteria of mechanical seals for solid particle-containing media
Selection criteria of mechanical seals for solid particle-containing media
10/02/2022industry news
In selection of mechanical seals, solid particle-containing media such as tower bottom residual oil, oil slurry, and crude oil have their own specific standards.
This is determined by characteristics of these media. Characteristics of media containing solid particles are:Solid particles can cause severe wear on sealing end faces.Deposition of solid particles on rotary face will make rotary face lose its floatability, and particles depositing on spring will affect elasticity of spring.
These features imply the following requirements for mechanical seals: Friction pairs are wear-resistant and solid particles must be excluded from the mechanical seals or the latter can prevent solid particles from precipitating.
Therefore, the following selection criteria are proposed for the machine seal:1. Pressurized double seal should be adopted, and isolation fluid should be introduced into sealing cavity. Friction pair near the medium side should adopt material combination of silicon carbide Vs silicon carbide.
2.If a single mechanical seal is used, a fluid with a slightly higher pressure than the sealed medium should be introduced from outside for flushing. When the sealed medium is used for flushing,solid particles should be separated before entering the sealing cavity, and a large spring type Sealing structure should be used.