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Some bearings use a thick grease for lubrication, which is pushed into the gaps between the bearing surfaces, also known as packing. The grease is held in place by a plastic, leather, or rubber gasket (also called a gland) that covers the inside and outside edges of the bearing race to keep the grease from escaping.Bearings may also be packed with other materials. Historically, the wheels on railroad cars used sleeve bearings packed with waste or loose scraps cotton or wool fiber soaked in oil, then later used solid pads of cotton.

Sleeve bearings use two surfaces lubricated with oil or grease as a friction contact. They often use porous sintered sleeves to be self-lubricating, requiring only infrequent maintenance or replacement. Sleeve bearings are less durable at higher temperatures as the contact surfaces wear and the lubricant dries up, eventually leading to failure; however, lifetime is similar at relatively low ambient temperatures. [Sleeve bearings] may be more likely to fail at higher temperatures, and may perform poorly when mounted in any orientation other than vertical. The lifespan of a sleeve-bearing fan may be around 40,000 hours at 50 °C. Fans that use sleeve bearings are generally cheaper than fans that use ball bearings, and are quieter at lower speeds early in their life, but can become noisy as they age.

Rifle bearings are similar to sleeve bearings, but are quieter and have almost as much lifespan as ina bearings. The bearing has a spiral groove in it that pumps fluid from a reservoir. This allows them to be safely mounted with the shaft vertical (unlike sleeve bearings), since the fluid being pumped lubricates the top of the shaft.The pumping also ensures sufficient lubricant on the shaft, reducing noise, and increasing lifespan.

Though generally more expensive, ball bearing fans do not suffer the same orientation limitations as sleeve bearing fans, are more durable at higher temperatures, and are quieter than sleeve-bearing fans at higher rotation speeds. The lifespan of a ball bearing fan may be over 60,000 hours at 50 °C.

The sleeves facilitate bearing mounting and dismounting and often simplify bearing arrangement design.When sealed bearings are to be mounted on an adapter sleeve it is necessary to protect the sealing lips from being damaged. This can be done by using an E-design adapter sleeve,inserting an intermediate ring between the skf bearing and the locking washer. 

To seal efficiently, radial shaft seals must run against a smooth, round counterface. If the counterface becomes worn, the seals will no longer be able to fulfil their function, which is to retain lubricant and exclude contaminants.