Roller bearings consist of an inner ring, an outer ring, and a set of rollers that are held between the two rings. The rollers are typically cylindrical but can also be tapered or needle-shaped. The inner and outer rings are typically made of steel, while the rollers are made of steel or a harder material such as ceramic or tungsten carbide.
There are several types of roller bearings, each with unique characteristics and applications. The most common types include:
Cylindrical roller bearings consist of an inner ring, an outer ring, and a set of cylindrical rollers that are held between the two rings. The cylindrical rollers are usually guided by a cage that separates the rollers and helps to distribute the load evenly.
Cylindrical roller bearings are designed to handle heavy radial and low-thrust loads at high speeds. They are commonly used in industrial machinery, such as conveyors, fans, pumps, and gearboxes.
They come in several subtypes, including single-row, double-row, and multi-row cylindrical roller bearings. Single-row cylindrical roller bearings are the most basic type and are suitable for most standard applications, while double and multi-row bearings are designed to manage heavier loads.
Needle Roller Bearings
Needle roller bearings are a type of roller bearing that uses needle-shaped rollers. They are characterised by their small size and high load-carrying capacity.
Despite their small size, needle roller bearings can support heavy radial loads and are ideal for use in applications where space is limited. Common applications include domestic appliances, electric motors, and automotive transmissions.
Spherical Roller Bearings
Spherical roller bearings are a type of roller bearing that is capable of handling both heavy radial and thrust loads. They consist of an outer ring, an inner ring, and a set of spherical rollers that are held between the two rings. The inner ring has two raceways, and the rollers are shaped to match the raceways, supplying support and stability.
They are unique in that they are designed to accommodate misalignment and are commonly used in applications where shaft deflection or misalignment is a concern. Spherical roller bearings are commonly used in industrial machinery and construction.
Tapered Roller Bearings
Tapered roller bearings have a unique design. The rollers have a different diameter at each end, which creates a tapered shape. This design allows for a greater contact surface between the inner and outer races, making them ideal for handling heavy radial and thrust loads simultaneously.
They are a versatile choice, commonly used in automotive applications as well as industrial machinery. They are also suitable for use in applications where there is a need for precise shaft alignment and support for heavy radial loads.
Thrust bearings are specific rotary bearings used to handle high loads in hostile environments. They may feature various rolling elements, including needles, tapered, spherical, or cylindrical rollers, which divide the bearing rings. Thrust rollers handle axial and thrust loads parallel to the shaft's axis. Their speed rating varies based on the rolling element used. For instance, ball roller thrust bearings are excellent for high-speed applications, but cylindrical roller thrust bearings are limited to moderate speeds.
Cross Roller Bearings are a type of roller bearing with high rotation accuracy capable of bearing loads in every direction. Because it has orthogonally arranged cylindrical rollers, it can bear loads in every direction. This lets one crossed roller bearing replace more than one ball bearing, thus saving the space required by ball bearings, lowering the associated material costs.
