Why use motor bearing? How to identify the bearing

Commonly used motor bearing type there are three main varieties: rolling bearing, sliding bearing and oil bearing, rotating support motor rotating components. Micro or small motor common choose oil-retaining bearing, less accessories, maintenance free, to simplify the structure; Sliding bearing is mainly used in large motor, suitable for overload and impact resistance; Rolling bearings used most widely, the following Ms. And discuss the topic is aimed at this kind of bearing. How to identify the bearing rolling bearing code consists of pre codes, codes of fundamental and suffix code, front code by letters, meaning for the complete set of bearing branch; Fundamental symbol of said bearing type and size of main feature; Suffix code said bearing accuracy and data features. Rear bearing codes and their meanings commonly used low internal structure symbol meaning the sample B - — The contact Angle of 40 ° C - angular contact ball bearing — Contact Angle is 15 ° angular contact ball bearing AC - — Contact Angle of 25 ° angular contact ball bearing E - — Enhanced design low seal dustproof and external appearance change symbol and meaning example code meaning symbol meaning N bearing outer ring has anti-rotation slot ( 2) RZ non-contact seal NR bearing outer ring has locking slot and stop ring bearing ( 2) Z dust cover sealed bearing ( 2) RS contact seal bearing ( 2) LS contact seal bearing ( Inner ring without the threaded) Low frame structure, data code symbol meaning of symbol meaning F steel class entity adhere to frame, the attached Numbers represent different information J stamping steel frame Q bronze entities keep on keeping on, after different information with digital representation V full rolling element M brass entity insist E phosphating treatment do T phenolic laminated tube distribution entity insist frame D carbonitriding do TN engineering plastic mold injection persist aircraft low tolerance grade code P0 - — Dimensional accuracy level for P0 P6 - — Dimensional accuracy level for P6 P5 - — Dimensional accuracy for P4, P5 class - — Dimensional accuracy for P4 level P2 - — Dimensional accuracy for P2 level precision of the rolling bearing from 0 level up progress in turn. Low clearance code symbol meaning/C1 radial clearance for 1 group/C2 radial clearance of 2 - — Radial clearance is zero, namely ordinary clearance/C3 radial clearance for the 3 groups/C4 radial clearance group/C5 radial clearance for 4 to 5 groups/CM for motor bearing clearance low vibration level code Z - — Bearing vibration acceleration level extremum categories, from low to high as follows: Z1, Z2, Z3, Z4V - — Bearing vibration velocity magnitude extreme value categories, from low to high as follows: V1, V2, V3 and V4 configuration code symbol meaning DB device back to back in pairs, example: 7210 c/DBDF paired device, face to face: 32205 / DFDT series device in pairs, example: 7210 c/DT bearing seal structure 2 z - — With dust cover bearing used in pollution is not serious and there is no water, steam and other contact bearing the risk of bearing configuration. Dust cover is also used in the speed or thinking about operating temperature, it is very important to reduce friction applications. 2RZ— — Non-contact seal bearings are often used for pollution is not very serious, application and dust cover, slightly better than dust cover sealing effect. 2RS— — With the contact seal ( Referred to as the seals) Bearings are often used in secondary pollution, such as the splash of water or water shall not prevent, or request without maintaining long-term use life of the bearings in the configuration. About the motor bearing clearance's radial bearing ( The axial) Clearance is when no bearing load function, relative another ring, a ring from a radial ( The axial) Limit position to move to the opposite extreme position of the radial ( The axial) Interval. Due to the shape of the ring in the ideal error and rolling body not divisive, it should be adopted in different direction of the ring and ring and different relative position of the radial roller ( The axial) Displacement of the uniform value. Low clearance is an important technological parameters of the bearing, it directly affects the bearing load distribution, vibration, noise, friction, temperature rise, utilizing life running accuracy and mechanical and other technical performance. 一) Clearance is too large, will make up the bearing internal load decreases, and the contact stress increases, so as to shorten the life. Excessive clearance will also landed the bearing running accuracy, vibration and noise. b） Clearance is too small, may be negative clearance in the operation of practice ( Interference) Increases, provoked the friction heat, temperature rise, progress and make less effective clearance or interference is bigger, so a vicious circle will cause bearing lock.