NSK 53309 dimensions and axial-load reference
Read the complete assembly size
NSK 53309 is a single-direction thrust ball bearing reference with aligning seat. Its nominal assembly envelope is 45×85×30.1 mm: shaft bore d = 45 mm, overall diameter D = 85 mm and total height T3 = 30.1 mm. A loose washer or cage measurement is not the height of the complete assembly.
Axial direction and support arrangement
This separable construction uses a shaft washer, a ball-and-cage assembly and a housing washer. It supports axial force in one direction. This is a thrust-only construction. It cannot be chosen as the sole radial support for a shaft. Radial force and overturning loads need a separately verified support arrangement.
Axial ratings, not permissible working loads
The printed basic dynamic axial rating is Ca = 80.5 kN and the basic static axial rating is C0a = 163 kN. These values belong to the catalogue assembly and standard cage. They are not radial Cr/C0r values and do not by themselves establish an allowable operating load or a guaranteed life.
Speed and lubrication
The catalogue lists 2000 r/min for grease lubrication and 3000 r/min for oil lubrication. These are lubrication-specific limiting speeds, not permission to run every installation continuously at that speed. The actual load, lubricant delivery, temperature and heat removal still need checking. A minimum axial load is required to avoid ball/washer slippage; this source table does not provide a model-specific minimum-load force.
Installation checks before selecting this model
Identify the shaft washer by the d bore and distinguish it from the housing washer with bore D1 = 47 mm. Keep the raceway faces towards the balls. Confirm the seating surfaces, shoulders, fillets, retention and separate radial support against the machine drawing. The mounting dimensions in the parameter table are geometric references, not a complete machine assembly procedure.
Aligning seat versus the U assembly
This catalogue designation has an aligning seat but is not the U-listed assembly with a separate aligning seat washer. Its height T3 = 30.1 mm must not be replaced with the flat-seat or U-assembly height. Confirm the matching seating arrangement; no universal allowable misalignment angle is supplied by this table.
Selection and mounting limits
- No machine fitment or direct replacement approval follows from equal boundary dimensions. Compare the construction, load directions, ratings, speed, fits and full marking.
- No grease fill, temperature limit, installed preload, retaining-nut torque, numerical clearance or CAD file is established by these table rows. Missing information has not been borrowed from another model.
- The standard-cage ratings can change if the cage or number of balls changes. A different suffix requires its own specification.
Different seat constructions in this source row
These links describe different assemblies, not approved substitutes:NSK 51309·NSK 53309U.
Technical basis:NSK Rolling Bearings for Industrial Machinery, E1103d (2025), Part C, C298–C299; construction and identification C296–C297. Source checked 2026-10-01. BearingScope independently organises factual catalogue data for lookup and comparison; it does not sell bearings or approve machine modifications.
Thrust ball bearing size and construction guide·Search by dimensions·Compare recorded models
Product specifications
Metric and imperial values are paired where the manufacturer provides both. Expand a section to review its parameters.
Core specifications5 parameters
| Parameter | Symbol | Value |
|---|---|---|
| Variant / construction | Axial deep groove ball bearing | |
| Bore diameter | d | 45 mm |
| Outside diameter | D | 85 mm |
| Width | B | 30.1 mm |
| Mass | ≈m | 0.702 kg |
Mounting dimensions3 parameters
| Parameter | Symbol | Value |
|---|---|---|
| Minimum shaft abutment diameter | da min. | 69 mm |
| Maximum housing abutment diameter | Da max. | 61 mm |
| Maximum housing-side fillet radius | ra max. | 1 mm |
Aligning-seat geometry2 parameters
| Parameter | Symbol | Value |
|---|---|---|
| Aligning-seat geometric reference | A | 25 mm |
| Spherical seat radius | R | 64 mm |
Assembly boundary dimensions3 parameters
| Parameter | Symbol | Value |
|---|---|---|
| Shaft-washer bore diameter | d | 45 mm |
| Overall outside diameter | D | 85 mm |
| Complete assembled height | T3 | 30.1 mm |
Axial load ratings2 parameters
| Parameter | Symbol | Value |
|---|---|---|
| Basic dynamic axial load rating | Ca | 80500 N |
| Basic static axial load rating | C0a | 163000 N |
Chamfers1 parameter
| Parameter | Symbol | Value |
|---|---|---|
| Minimum housing-side chamfer | r min. | 1 mm |
Component dimensions2 parameters
| Parameter | Symbol | Value |
|---|---|---|
| Shaft washer outside diameter | d1 | 85 mm |
| Housing washer bore diameter | D1 | 47 mm |
Construction3 parameters
| Parameter | Symbol | Value |
|---|---|---|
| Axial load directions | One direction | |
| Seat construction | Aligning seat | |
| Radial-load support | Not suitable for radial load; separate radial support required |
Lubrication-qualified speed2 parameters
| Parameter | Symbol | Value |
|---|---|---|
| Limiting speed — grease | 2000 r/min | |
| Limiting speed — oil | 3000 r/min |
Mass reference1 parameter
| Parameter | Symbol | Value |
|---|---|---|
| Approximate assembly mass | 0.702 kg |