Lip seals; it sounds like such a funny thing to say, as if you needed glue to seal your lips. However, that is not what lip seals are. They are actually a special type of seal that covers openings in industrial equipment. They are named lip seals because the seals have "lips," or elevated edges around the seal. The "lips" form a tighter seal to the openings to which they are attached. There are three kinds of lip seals and each has its own job.
Single Lip Seals
As the name implies, these seals have a single outside lip. Inside, there is typically a spring that helps the seal recoil over an opening. They are required for any machine opening that needs to open just a little bit and then quickly close. The spring also makes it easier for the single lip seals to be removed.
Double Lip Seals
Double lip seals have a concentric circle inside the original outer lip of the seal. If you can picture a rubber washer, but with a "wall" surrounding the outside edge and a "wall" around the inside edge, that is what a double lip seal looks like. Double lip seals may be used in place of single lip seals when there is greater pressure or force involved. The double seal is reinforced this way to stop the pressure or force behind it from forcing it off of the machine components to which it is attached.
Oil seals are made to resist slippage due to the amount of oil passing through machine components. A well-lubricated metal seal, like those above, would slip off too often, but the oil seals are designed not to slip at all. They are difficult to change because of that fact, but then they are also guaranteed to stay in place while tons of oil are forced through the center of the seal. Most often, they are used in the processing of fossil fuels to prevent leaks and the loss of precious oil.
Need New Lip Seals?
If a repair technician says that a piece of machinery in your industrial plant needs new lip seals, rest easy. Most of the time these seals are relatively inexpensive. The technician probably has exactly what your machine needs, and he or she can install the lip seals for you. Otherwise, you can buy lip seals factory direct from the manufacturer. Contact companies like Accurate Products Inc. for more information.