Bearing seals are always installed to help in the retaining lubricants and to prevent contamination of the bearing race. Visit www.ttv-gmbh.de/dichtungstechnik to see the variety of seals available. Seals should always provide a minimum amount of friction and wear since the bearing performance are linked to the effectiveness of the seals.
Understand the type of seals available
1. Contact seals
They provide an effectively sealed surface through continuous application of pressure to the surface area. They secure difficult penetration of solid particles and fluid which however can lead to direct contact with the shaft creating friction and heat leading to damaged shaft finish.
2. Non-contact seals
They yield much less heating and friction compared to contact seals but can let lubricant leak out of the bearing chamber. They can also allow entrance of the contaminants. They are suitable when grease lubricants are used.
3. Bearing isolator seals
They combine the functions of contact seals and non-contact seals leading to the provision of more protection than individual contact or non-contact seals.
Bearing isolator seals can be used with either oil or grease lubricants but a bit more expensive than the first two. They also need more physical space compared to contact and non-contact seals.
Features of the correct bearing seals
1. Bearing type
When choosing the correct bearing seal, you need to know the bearing you are using. There are some bearing types which have unique features and are used for different conditions.
Some of the common types of the bearing are the roller bearing, ball bearing, ball thrust bearing; tapered roller thrust bearing, and roller thrust bearing. Different type of bearing seals will be suitable for different type of bearing.
2. Type of lubrication
The lubricant used in the bearing plays a big part when it comes to selecting the correct bearing seals to use. There are some bearing seals suitable for oil and others suitable for grease lubricated bearings.
3. Physical space available
Physical space available will determine the types of seals to be used. Bearing isolators seals will require more physical space as compared to contact or non-contact seals.
4. Seal friction and consequent heating
Much friction and consequent heating are mainly found in the contact seals. If this is a consideration, then non-contact is preferred.
5. Justifiable costs
Different types of bearing seals are priced differently. Bearing isolator seals are a bit more expensive compared to contact and non-contact seals. When spending extra, it is important to ask yourself if the extra cost is justified.