11-18-2021, 08:07 AM
Bearings are used to help reduce friction. Metal-upon-metal contact produces large amounts of friction. The friction adds to wear and tear of the metal, producing grinding that slowly degrades the metal. Bearings reduce friction by having the two surfaces roll over each other, reducing the amount of friction produced. They consist of a smooth metal ball or roller that rolls against a smooth inner and outer metal surface. The rollers or balls take the load, allowing the device to spin.
The contact points between the ball and the outer race is very small due to the spherical shape of the bearing. This also helps the ball spin very smoothly. Since the contact point is so small, the flanged bearing can become overloaded at a specific point causing the ball bearing to become deformed. This will ruin the bearing. Ball bearings are typically used in applications where the load is relatively small.
2. The table above lists some general types of ball bearings and their typical load capabilities.
Straight Roller Bearings
Straight roller or cylindrical bearings run in cylindrical raceways and have low-friction, high-radial load capacity, and high speed capability. Roller bearings are cylinder-shaped stainless bearings where the point of contact between the bearing and the race is a line rather than a point. Load is distributed over a larger area and allows the bearing to handle a greater load. To minimize its tendency to skew, the roller’s length is not much greater than the diameter of the roller.
Their usual design is free to float axially, and they have roller-guiding flanges on both sides of one ring and none on the other side. This allows for the bearing to expand due to thermal activity when used in combination with a ball miniature bearing’s fixed location at the opposite end. A thrust load can be supported in one direction if a guiding flange is added on one of the opposing rings’ side. A second flange can be added for two-directional thrust capacity.
5. Tapered bearings are mounted pairs since they handle radial loads better than a single row of tapered small size bearings. For heavy-duty applications, two or four rows of tapered rollers are combined in a single unit in large bearings.Spherical roller bearings typically consist of two rows of barrel-shaped rollers running in two raceways. One is on the inner ring and the other is on a continuous spherical surface ground on the inner diameter of the outer ring. This allows the bearing to operate with some misalignment. Spherical rollers have barrel profiles that closely match the raceways profiles, hence making them robust and having a high load capacity. They are mounted in pairs inside the large size bearing housing and are faced in opposite directions. This is done so that the load can be supported in either direction.
Ball-thrust bearings are comprised of two grooved plates with a set of balls between them. The ball-race contacts have a sliding action that is increased at high speeds by the centrifugal force on the balls. Cylindrical roller thrust middle size bearings are limited to about 20% of the speed of its radial bearing counterpart and ball-thrust bearings are limited to 30% of the speed of their counterpart.
The contact points between the ball and the outer race is very small due to the spherical shape of the bearing. This also helps the ball spin very smoothly. Since the contact point is so small, the flanged bearing can become overloaded at a specific point causing the ball bearing to become deformed. This will ruin the bearing. Ball bearings are typically used in applications where the load is relatively small.
2. The table above lists some general types of ball bearings and their typical load capabilities.
Straight Roller Bearings
Straight roller or cylindrical bearings run in cylindrical raceways and have low-friction, high-radial load capacity, and high speed capability. Roller bearings are cylinder-shaped stainless bearings where the point of contact between the bearing and the race is a line rather than a point. Load is distributed over a larger area and allows the bearing to handle a greater load. To minimize its tendency to skew, the roller’s length is not much greater than the diameter of the roller.
Their usual design is free to float axially, and they have roller-guiding flanges on both sides of one ring and none on the other side. This allows for the bearing to expand due to thermal activity when used in combination with a ball miniature bearing’s fixed location at the opposite end. A thrust load can be supported in one direction if a guiding flange is added on one of the opposing rings’ side. A second flange can be added for two-directional thrust capacity.
5. Tapered bearings are mounted pairs since they handle radial loads better than a single row of tapered small size bearings. For heavy-duty applications, two or four rows of tapered rollers are combined in a single unit in large bearings.Spherical roller bearings typically consist of two rows of barrel-shaped rollers running in two raceways. One is on the inner ring and the other is on a continuous spherical surface ground on the inner diameter of the outer ring. This allows the bearing to operate with some misalignment. Spherical rollers have barrel profiles that closely match the raceways profiles, hence making them robust and having a high load capacity. They are mounted in pairs inside the large size bearing housing and are faced in opposite directions. This is done so that the load can be supported in either direction.
Ball-thrust bearings are comprised of two grooved plates with a set of balls between them. The ball-race contacts have a sliding action that is increased at high speeds by the centrifugal force on the balls. Cylindrical roller thrust middle size bearings are limited to about 20% of the speed of its radial bearing counterpart and ball-thrust bearings are limited to 30% of the speed of their counterpart.