Comparing Bearings In Computers - Part 2

Comparing Costs

When purchased in bulk quantities, a sleeve bearing is a far cheaper alternative to its ball bearing counterpart. However, a ball bearing can provide a greater value for money as they can operate at higher temperatures and last for several thousands of hours longer depending on the operating temperature.

The heat endurance is far greater in a ball bearing than that in a sleeve bearing and there are far more fan mounting option available for a ball bearing. This is important when space saving becomes an issue or a priority. With a ball bearing fan, the fan can be mounted vertically, parallel, perpendicular or shaft center line, whereas the sleeve bearing can only operate vertically.

At the highest speeds, a ball bearing is much quieter than a sleeve bearing, but in its infancy, a sleeve bearing will be quieter at lower speeds. Shaft bearings are not made as precisely as a ball bearing and there is more evaporation of lubricant in a sleeve bearing than in a ball bearing.

Keep Down The Noise!

Reducing noise is important when creating a new product; this is especially true in the modern office where there are several computers, sometimes hundreds in one space. This tends to be more of a concern for manufacturers and designers of products which will be in the European market rather than for the American one.

For very low fan speeds, sleeve bearings offer a quieter operation than that of a ball bearing. With technology of today however, it is possible for a ball bearing to run at the same noise level as a sleeve bearing thanks to new pre-loading technology. Noise levels will vary depending on the component parts.

Keeping It Slick

Poor lubrication in computer systems has to potential to result in a complete system failure should the cooling parts stop functioning correctly and certain electronic parts become overheated. In order to minimise friction and wear and thereby reduce the chances of overheating, special lubricants are used to keep the parts working correctly. Thick lubricant is used in ball bearings, where the ingredients ensure that the lubricant will not evaporate too quickly, keeping the system running for longer.

In sleeve bearings the brushings of the bearing can only hold a certain about of lubricant, meaning that as there is no easy way to recharge the lubricant, it is far more likely to stop working as the evaporation process takes hold.