Supplementary Marks for Spindle Bearings: A Comprehensive Guide
Spindle bearings are high-precision bearings specifically designed for applications with high rotational speeds and axial as well as radial loads. Selecting the right spindle bearing requires an understanding of the various suffixes used by different manufacturers.
This guide helps you interpret the trailing characters and select the optimal bearing for your application..
1. spindle bearing series
70, 72, 79: These are the basic bearing series that define the size and general characteristics of the bearing. Each series has specific dimensions and load ratings.
2. Bore index
16: Indicates the inner diameter of the bearing in mm.
3. Accuracy class
P4, P3, P2: Defines the running accuracy and dimensional accuracy of the bearing. P4 is the highest accuracy class (ABEC 7), while P2 is the lowest (ABEC 9).
4. Preload
L, M, H: Indicates the preload of the bearing (light, medium, strong). Preloaded bearings have higher stiffness and running accuracy.
Gxx, CPxx, CAxx: Specify the preload in Kgf (Gxx) or µm (CPxx for average preload, CAxx for average axial clearance).
5. Arrangement
SU, DU: Defines whether it is a single-row (SU) or double-row (DU) bearing.
DB, DF, DT, DBD, DFD, DTD, DUD: Indicate the number of bearings in a sentence (two-bearing sentences, three-bearing sentences).
DBB, DFF, DBT, DFT, DTT, QU: Identifies four-piece bearing.
6. Sealing
Without labeling: Open bearing without seal.
VIV: Non-abrasive elastomer seal for low friction resistance.
2RS, 2RZ: Both-sided grinding seals made of nitrile rubber (other manufacturers).
7. Cage
TR: Hard tissue cage for high speeds and temperatures.
TYN: Polyamide cage for quiet operation and good emergency running properties.
J, M, MA: Steel sheet cages (other manufacturers).
8. Material
Without designation: Rolling bearing steel (SUJ2)
SN24: Ceramic balls for high speeds and temperature resistance.
E, ES: Stainless steel (other manufacturers).
9. Contact angles
A: 30°, A5: 25°, C: 15°: Defines the contact angle of the bearing, which affects the axial load capacity.
10. Additional trailing characters (manufacturer-specific)
Lubrication: Grease or oil lubrication, special lubricants.
Tolerances: Deviations from the standard dimensions.
Special designs: hybrid bearings, coated bearings, etc.
Manufacturer
NSK: Use the aforementioned continuation marks .
SKF: Explorer bearing designation system with similar but slightly different designations.
FAG: Similar designation system as SKF.
INA: Similar designation system as FAG.
Recommendation
Always consult the manufacturer catalogs for detailed information on the replacement characters and the available bearing types.
Consider the specific requirements of your application to select the optimal spindle bearing.
With this knowledge, you are now well-equipped to understand the suffix codes of spindle bearings and make the right choice for your application..