Classification of Bearings

Add the first or first and second numbers from left to right

"6" denotes deep groove ball bearings (Category 0)

"4" denotes double row deep groove ball bearings (Category 0)

"2" or "1" denotes self-aligning ball bearings (four numbers for basic models) (Category 1)

"21", "22", "23" and "24" denote self-aligning roller bearings. (3 kinds)

"N" denotes cylindrical roller bearings (including short cylindrical rollers and parts of slender needles) (Category 2)

The inner ring of "NU" has no blocking edge.

"NJ" inner ring single baffle.

"NF" outer ring single sidewall.

The outer ring of "N" has no blocking edge.

"NN" double row cylindrical rollers, the outer ring without edge.

"NNU" double row cylindrical roller, inner ring without edge.

Roller length is at least five times the diameter of the size, known as needle roller bearings (category 4)

"NA" Spinning Needle Roller Bearing for Outer Ring

"NK" Rotary Cutting Needle Roller Bearing

"K" needle roller and cage assembly, without inner and outer rings.

"7" denotes angular contact ball bearings (Category 6)

"3" denotes tapered roller bearings (metric system) (Category 7)

"51", "52" and "53" denote centripetal thrust ball bearings (five numbers for basic models) (8 categories)

"81" Short Cylindrical Roller Bearings for Thrust (Category 9)

"29" Represents Thrust Self-aligning Roller Bearings (Category 9)

National Standard for Bearing

Size and tolerance of stop grooves and rings on outer rings of rolling bearings

GB-T 308-2002 Rolling Bearing Steel Ball

GB-T 309-2000 Rolling Bearing Roller Needle

Cylindrical Rollers of Rolling Bearings GB-T 4661-2002

Rated static load of rolling bearings GB-T 4662-2003

Rated dynamic load and rated life of rolling bearings GB-T 6391-2003

JB-T 3034-1993 Rolling Bearing Oil Seal Anti-rust Packaging

Measurement Method of Radial Clearance of JB-T 3573-2004 Rolling Bearing

JB-T 6639-2004 Technical Specifications for Frame NBR Sealing Ring for Rolling Bearing Parts

Residual magnetic field of JB-T 6641-2007 rolling bearing and its evaluation method

Measurement and Evaluation Method of Roundness and Ripple Errors of Rolling Bearing Parts JB-T 6642-2004

JB-T 7048-2002 Engineering Plastic Holder for Rolling Bearing Parts

JB-T 7050-2005 Cleanness Evaluation Method for Rolling Bearings

Measurement and Evaluation of Surface Roughness of Rolling Bearing Parts JB-T 7051-2006

JB-T 7361-2007 Hardness Test Method for Rolling Bearing Parts

Technical Specifications for JB-T 7752-2005 Rolling Bearing Sealed Deep Groove Ball Bearing

JB-T 8196-1996 Rolling Bearing Roller Residual Magnetism and Its Assessment Method

JB-T 8571-1997 Test Rules for Dust-proof, Grease Leakage and Temperature Rise Performance of Rolling Bearings Sealed Deep Groove Ball Bearings

JB-T 8921-1999 Inspection Rules for Rolling Bearings and Their Parts

Supplementary Technical Conditions for JB-T 10336-2002 Rolling Bearings and Their Parts

Rules for life and reliability test of JB-T 50013-2000 rolling bearings

JB-T 50093-1997 Test Evaluation Method for Life and Reliability of Rolling Bearings

Pre-code

The front code R is placed directly before the basic code of the bearing, and the other codes are separated by small dots from the basic code.

GS. - Thrust Cylindrical Roller Bearing Ring. Example: GS.81112.

K. - Combination of rolling element and cage. Example: Thrust cylindrical roller and cage assembly K. 81108

R - Bearings without separable inner or outer rings. Example: RNU207 - NU207 bearing without inner ring.

WS - Thrust Cylindrical Roller Bearing Axle Ring. Example: WS.81112.

—— Internal design

—— Shape Size and Deformation Design

—— Sealing

—— cage

—— Tolerance

—— Clearance

—— Heat treatment

—— Special Design

—— Spindle Bearing of Machine Tool

—— Low Noise and Low Bearing

Postcode

The post code is placed after the basic code. When there are multiple groups of post codes, they shall be arranged from left to right according to the sequence of post codes listed in the bearing code table. Some postcodes are preceded by small dots and basic codes.

Postcode-internal structure

A, B, C, D, E - Changes in Internal Structure

Example: Angular contact ball bearings 7205C, 7205E, 7205B, C-15 degree contact angle, E-25 degree contact angle, B-40 degree contact angle.

Example: Cylindrical roller, self-aligning roller and thrust self-aligning roller bearings N309E, 21309E, 29412E - reinforced design, bearing load capacity improved.

VH - Roller self-locking cylindrical roller bearing with full roller (the complex diameter of the roller is different from the standard bearing of the same type).

Example: NJ2312VH.

Rear Code-Bearing Shape Size and External Structure

DA - Separable double row angular contact ball bearing with double inner rings. Example: 3306DA.

DZ - cylindrical roller bearing with outer diameter. Example: ST017DZ.

K - tapered hole bearing, taper 1:12. Example: 2308K.

K30-tapered hole bearing, taper 1:30. Example: 24040 K30.

2LS - Double row cylindrical roller bearing with dustproof cover on both sides of double inner ring. Example: NNF5026VC.2LS.V - Internal structure change, double inner ring, dustproof cover on both sides, full roller double row cylindrical roller bearing.

N - Bearing with stop groove on outer ring. Example: 6207N.

NR - bearing with stop groove and ring on outer ring. Example: 6207 NR.

N2 - - Four-point contact ball bearing with two stop grooves on the outer ring. Example: QJ315N2.

S - Outer ring bearing with lubricating oil groove and three lubricating oil holes. Example: 23040S. The aligning roller bearings with bearing outer diameter D (> 320mm) are not marked with S.

X - Shape size conforms to international standards. Example: 32036X

Z * Technical conditions for special structures. Arrange downwards from Z11. Example: Z15 - stainless steel bearing (W-N01.3541).

ZZ - Roller Bearing with two guide rings.

Post Code-Sealing and Dust Prevention

RSR - Bearing side with sealing ring. Example: 6207 RSR

2 RSR - bearing with sealing rings on both sides. Example: 6207.2