Bearing Designation

In order to identify the bearings, a complete designation system is required so that the product can be easily recognized and called by the engineers, suppliers, manufacturers, customers, distributors, etc. Hence our BELGO bearings follow a designation system. Our complete bearing designation is always marked on the bearing package with the label and on the bearing itself. Due to the basic designation, the following ones can be recognized by our stakeholders such as; the bearing type, the basic design, the boundary dimensions.

Prefixes and suffixes show that bearing components or variants having a design and/or feature(s) that distinguishes in some respect from the basic design


Prefixes consists of letters are used to identify the material, other than steel for bearings or component parts of bearing. The prefix identifying the material is separates from the rest of designation by a horizontal line.

Prefixes describing the Materials

H  heat-resisting steel (e.g.Belgo NUP 205)

M  copper alloy (e.g. Belgo M 6010)

S  plastics,glass,ceramics,etc  (e.g. Belgo S 6208)

SS  Stainless steel ((e.g. Belgo SS 6205)

T  case-hardening steel (e.g. Belgo T 35375)

Prefixes describing the special designs or parts of bearings

K  Cage with Rolling elements of dismountable bearing

(e.g.Belgo KNU 210)

L  – Free ring of dismountable bearing(interchangeable ring,

e.g. Belgo L 30208)

R  – Dismountable bearing without free ring (e.g. Belgo RNU 209)

E  – Shaft washer of thrust ball bearing (e.g. Belgo E 51207)

W – Housing washer of thrust ball bearing  (e.g. Belgo W 51208)


It is used to recognize the constructive modifications of the bearings from its original design. The suffixes are categorized in a few groups:

Category a  : Modification of internal design with increased basic load (e.g A,C,E etc.), contact angle (e.g. A,B,C)

Category b  : Modifications of external design tapered bore,groove on outer ring etc. (e.g. Belgo 30218 A,1210 K,6208NR,6308-2RS)

Category c  :  Modifications of cage design, material, guiding surfaces etc. (e.g. Belgo 6206 TN, Belgo NU308 MA)

Category d  :  Modifications from normal design based on tolerance classes bearing radial or axial clearance stability of dimensions at high temperatures, bearing matching etc.