What are the bearing classifications?

Bearing classification

Rolling bearings are divided into 2 categories: radial bearings, thrust bearings

Radial bearings are divided into: deep groove ball bearings, radial thrust ball bearings, point (angular) contact ball bearings, spherical ball bearings, cylindrical roller bearings, needle roller bearings, tapered roller bearings, spherical roller bearings

Thrust bearings are divided into: thrust ball bearings, thrust angular contact ball bearings, thrust cylindrical roller bearings, thrust needle roller bearings, thrust tapered roller bearings, thrust self-aligning ball bearings

Bearing Seals

Seals can be divided into two categories, one is the bearing seal, one is the bearing dust cover. Bearing seals are important to their sealing performance and service life. The production material is rubber, mainly: nitrile rubber, hydrogenated nitrile rubber, fluorine rubber; and bearing dust cover is to prevent the bearing into dust and other debris affect the work, the production material is sheet metal, dust cover is a ring-shaped cover, usually made of sheet metal stamping, fixed in the bearing on a ring or gasket, as well as to another ring or gasket extension and blur bearing internal space, but not in contact with another ring or gasket.

Bearing outer ring

Bearing outer ring can also be called bearing outer ring or bearing sleeve, usually fixed on the bearing seat or housing, play a role in supporting the rolling body. The outer ring surface is equipped with a groove for rolling steel balls or rollers, called the outer groove or outer raceway.

Rolling body

Rolling body is the core component of rolling bearing, due to its existence, there is rolling friction between the relative moving surfaces. The types of rolling body are ball, cylindrical roller, tapered roller, needle roller, etc. The rolling body of rolling bearing mainly has 2 kinds of steel balls and rollers.

Bearing inner ring

The inner ring of a bearing can also be a bearing inner ring or bearing inner sleeve, usually fixed on the journal, the inner ring rotates with the shaft, the outer surface of the inner ring is a steel ball or roller rolling groove, called the inner groove or inner raceway.

Bearing cage

Bearing keep frame, also known as bearing keep frame, refers to the part wrapped all or part of the rolling body and make the corresponding movement to isolate the rolling body bearing parts, usually guide the rolling body and keep it in the bearing.

Inner ring, outer ring and cage and rolling body between the role of.

Inner ring and shaft with fixed bearing, provide rolling body half of the track, transfer load; outer ring and bearing housing with fixed bearing, provide the other half of the rolling track

Types of bearings and types

According to the shape of rolling body, bearings can be divided into two types of ball bearings and roller bearings.

The rolling body of the ball bearing and the raceway of the collar are in point contact, with low load self-lubricating bearing capacity and poor impact resistance, but low frictional resistance, high limiting speed and low price.

Roller bearing rolling body and collar raceway for line contact, load self-lubricating bearing capacity is high, impact resistance, but the friction resistance is high, the price is also relatively high.

2, according to the number of rolling body columns, bearings can be divided into single, double and multi-row bearings.

3、According to the work of sliding bearing can automatically adjust the heart, bearing can be divided into rigid bearings and spherical bearings.

Rolling bearing classification code

    ”0″—- double row angular contact ball bearing

  ”1″—- spherical ball bearing

  ”2″—- Spherical roller bearings and thrust spherical roller bearings

  ”3″—-Tapered roller bearings

  ”4″—-Double row deep groove ball bearings

  ”5″—-Thrust ball bearings

  ”6″—-Deep groove ball bearings

  ”7″—-Angular Contact Ball Bearings

  ”8″—-Thrust cylindrical roller bearings

  ”9″—-Thrust Tapered Roller Bearings

        N” —- cylindrical roller bearings and needle roller bearings cylindrical roller bearing code after the general will be attached to 1 or several letters code, used to indicate those retaining edge structure type , such as: NJ, NU, NUP and so on. For double-row or multi-row cylindrical roller bearings is indicated by the letter NN. Needle roller bearings are usually indicated by the letters NA or NK.

  ”U”—- outer spherical ball bearing

  ”QJ” —- four-point contact ball bearings

Rolling bearing classification

1, according to the bearing direction can be divided into radial bearing (bear radial force and not much axial force), thrust bearing (can only bear axial force) and radial thrust bearing (can bear radial force and axial force at the same time).

2, according to the shape of the rolling body can be divided into ball bearings, roller bearings and needle roller bearings.

3, according to the working conditions can be divided into ordinary bearings, high-speed bearings, high temperature bearings, low temperature bearings, vacuum bearings, anti-magnetic bearings, corrosion-resistant bearings, precision miniature bearings and extra-large bearings. China divided various types of rolling bearings into B, C, D, E, G 5 accuracy levels, B for the highest accuracy level, G for ordinary accuracy level, the most common application.

Rolling bearings are standard parts, produced in batches by specialized bearing factories. Design selection often need to consider factors such as life, load, accuracy, clearance (radial and axial), limit speed, friction torque, alignment performance, preload and rigidity, vibration and noise.

Compared with sliding bearings, the advantages of rolling bearings

1、Under general conditions, the efficiency of rolling bearings and liquid power lubrication bearings are equivalent, but higher than the mixed lubrication bearings;

2, radial clearance is relatively small, centripetal angular contact bearings available preload available preload to eliminate clearance, high running accuracy;

3, for the same size of the shaft diameter, rolling bearing width than the sliding bearing is small, can make the machine axial structure compact;

4, most rolling bearings can be radial and axial load at the same time, so the bearing combination structure is simple;

5, consume less lubricant, easy to seal, easy to maintain;

6、No need for useful non-ferrous metals;

7, high degree of standardization, batch production, low cost.

Compared with sliding bearings, the disadvantages of rolling bearings.

1、The ability to withstand shock load is poor;

2, high-speed heavy load bearing life is low;

3, vibration and noise is larger;

4, radial size than the sliding bearing.