How much do you know about packing seals ?
How to choose the sealing method when designing the machine? This article takes you to understand the common dynamic seal forms in mechanical design. They are packing seal, mechanical seal, dry gas seal, labyrinth seal,
oil seal, dynamic seal and spiral seal. Today, let's discuss the packing seal together first!
Packing seals can be divided into soft packing seals, hard packing seals, and molded packing seals according to their structural characteristics.
Soft packing type: Packing
Packing is usually woven from softer threads, which are filled in the sealed cavity by strips with a square cross-sectional area. The pressing force is generated by the gland to compress the packing and force the packing to be
pressed on the sealing surface (shaft). On the outer surface and the sealed cavity), the radial force for the sealing effect is generated, thus playing a sealing role.
Applicable occasions for soft packing:
The packing material selected for packing determines the sealing effect of packing. Generally speaking, packing materials are limited by the temperature, pressure and pH of the working medium, and the surface roughness and
eccentricity of the mechanical equipment on which packing works And line speed, etc., will also have requirements for the choice of packing material.
Graphite packing can withstand high temperature and high pressure, and is one of the most effective products to solve the problem of high temperature and high pressure sealing. Corrosion resistance, excellent sealing perform
-ance, stable and reliable function.
Aramid packing is a kind of high-strength organic fiber. The woven packing is impregnated with polytetrafluoroethylene emulsion and lubricant.
Polytetrafluoroethylene packing is made of pure polytetrafluoroethylene dispersion resin as raw material, first made into raw film, and then twisted, braided and woven into packing. It can be widely used in food, pharmaceuticals,
papermaking, chemical fiber, etc. Cleanliness requirements, and valves and pumps with strong corrosive media.
2. Hard packing seal
There are two types of hard packing seals: split ring and split ring.