The best way to seal your pump and valves is through compression packing. But it isn’t enough to do compression packing. You also have to know the right compression fibers to use. There are so many compression fibers out there that have specific applications they tend to.
Some of them include graphite, carbon, aramid, novoloid, etc. Each of these compression fibers will be looked at shortly.
If you’re going for graphite packing, you should try out graphite packing with aramid corners for lasting protection and seal.
For those who don’t know what compression packing is all about, not to worry! This article has got you covered.
What is compression packing?
Compression packing is made from various packing fibers, and it’s one of the oldest forms of sealing devices. It protects products from leakages and prolongs the lives of pumps, valves, and other rotating devices. You will always get value for your money if the compression packing installation is done properly.
How does it work?
It is made of relatively soft materials, so the packing compresses between the rotating body and the body of the valve or pump to create a seal, within the stuffing box.
There are three major things to look out for when choosing a compression packing. They are- the pH of the fluid being pumped, shaft speed (for the pumps), and fluid temperature.
Now, before you consider a compression packing, you should know the type of compression fiber you want to use.
Types of compression fibers
Graphite compression fibers
These fibers contain smooth, micro inorganic graphite. It is normally used in very high-temperature conditions and in equipment that has little to no chance of leaking. Such equipment are agitator shafts, plunger rods, valves, high-speed shafts, etc.
Furthermore, experts advise users to get graphite compression fibers for caustics, high-pressure steam, chemicals, and corrosive acids. It is mostly used in the nuclear industry.
This type of fibers thrives in abrasive environments. They can also be treated with PTFE and inert oil to increase resistance to oil, air, chemicals, caustics, gases, solvents, acids, etc.
It also serves as an anti-extrusion ring for abrasive services. The pH range is between 3 and 11. Using graphite fibers with aramid corners doubles the protection and resistance capacities.
This is one of the most popular and widely used fiber packing because it has excellent properties and it’s very versatile. It can withstand high shaft speeds and has good thermal conductivity.
Novoloid doesn’t contain any wax, sulfur, or silicone. So, if you don’t want to use graphite packing, this is your best alternative. It seals equipment in chemical and paper industries that graphite can’t.
It contains fluids that are used in reciprocating pumps, liquor pumps, washer journals, refiners, digesters, etc. The pH range is between 1 and 13, except for hot nitric or sulfuric acids.
These fibers function almost like graphic fibers. It uses different heat treatments to get the desired carbon content.