Spiral groove bearings are self-acting because their own rotation increases the pressure required to separate the bearing surfaces. Therefore, they are also non-contact bearings.
♦ Compared to tilting tile bearings, spiral groove bearings are easy and inexpensive to manufacture.
♦ Spiral groove bearings have zero wear during operation and can operate for long periods of time.
♦ Spiral groove bearings have excellent stability (all gas bearings have stability problems, spiral groove bearings are the best).
♦ Spiral groove bearings can be used in smaller equipment and maintain efficiency.
♦ They provide precise running positions for fine tip clearance and increased efficiency.
♦ They run well with gas or air lubricants, so they are completely oil-free, ideal for clean, green applications.
The flat thrust bearing is the most common type of spiral groove bearing and is so named because it consists of a flat surface opposite the groove surface.The variation in this type of bearing comes from the nature of the spiral surface and the type of fluid flow.
Hemispherical grease-lubricated spiral groove bearings for low-noise fans.
A spherical (or more commonly hemispherical) thrust bearing consists of a sphere that rotates concentrically in a spherical cup with a groove pattern.
In these bearings, a cone is cut out from the end of the cylindrical shaft. A groove is formed in the surface of the cone next to the cylindrical portion.
1.Spiral groove bearings are most successfully used in aircraft and ships for inertial gyroscopes.
2.Thrust bearings continue to be used in gyroscopes, such as the Hubble telescope.
3.A major application area is dry gas sealing, where spiral groove thrust bearings are used to lift the sealing surfaces apart, creating a narrow sealing gap and preventing contact and wear. These have been very successful and have been used in many industrial compressors.
4.Another notable use of spiral groove bearings is in cryogenic expanders. Here they are used to support the high speed rotation of the turbine and to xxx minimize power loss due to inefficiencies. The cryogenic expander extracts energy from the gas stream entering it, causing a rapid drop in temperature, and the extracted energy is used to rotate the turbine.