1 Model Information & Technical Parameters

Model：NN 3009 KTN/VQ497

Dimensions

Bore d：45 mm

Outer diameter D：75 mm

Width B：30 mm

Bore type: 1:12 tapered bore

Code Explanation

NN: Double row cylindrical roller bearing, inner ring double ribs, outer ring ribless, separable inner and outer rings

3009: Size series 30, size code 09, nominal bore 45 mm (medium cross-section balancing rigidity and rotational speed)

K: 1:12 tapered bore, preload adjustable via axial compression to expand inner ring

TN: Solid polyamide roller-guided cage, lightweight and low friction for improved thermal performance

VQ497: Stabilized heat treatment to minimize dimensional creep and shift under continuous operation and temperature cycling

Load Characteristics

Permitted load: Radial load only; axial load capacity negligible and cannot bear axial force independently

Structure: Separable design, inner ring double ribs, TN polyamide cage

Limiting speed: High load capacity with two roller rows; resin cage optimizes friction. Oil-air lubrication delivers optimal performance

Pre-grease: No pre-filled lubricant, lubricant added on assembly

Logistics & Industry Codes

Net weight：0.32 kg

Indicative carbon footprint：0.38 kg CO₂e

eClass code：23-05-09-01

UNSPSC code：31171505

Suffix Explanation

NN: Double row cylindrical roller bearing without outer ribs. Inner and outer rings separable. Two roller rows provide much higher radial rigidity than single-row bearings of equal size.

3009: Medium cross-section 30 series with high load capacity and rigidity, widely used on medium-heavy duty precision lathes and cylindrical grinders.

K: 1:12 tapered bore. Lock nut expands inner ring to set preload accurately during assembly.

TN: Standard polyamide roller-guided cage with low friction. Continuous operating temperature ≤120°C. TNHA reinforced cage alternative for sustained high speed.

VQ497: Special stabilized heat treatment reduces retained austenite and suppresses dimensional change under long continuous production runs.

Important reminder: Ribless outer ring cannot carry axial load alone. Spindle system must adopt matched precision angular contact ball bearings for axial support. Continuous temperature above 120°C is prohibited for TN cage. Preload must be precisely controlled for tapered bore; excessive preload causes overheating and premature fatigue. Hammer impact assembly forbidden; hydraulic nut pressing or thermal mounting recommended. Straight bore alternative: NN3009 TN/VQ497. Reinforced cage variant: NN3009 KTNHA/VQ497. /SP super precision suffix can be added.

2 Structure & Operating Characteristics

NN 3009 KTN/VQ497 precision double row cylindrical roller bearing achieves extremely high radial rigidity via dual roller rows to sustain heavy radial cutting loads. The 1:12 tapered bore enables flexible on-site preload adjustment. TN polyamide cage reduces frictional heat generation. VQ497 stabilized heat treatment greatly enhances long-term dimensional stability and prevents accuracy drift in continuous mass production. Separable rings simplify spindle disassembly and maintenance.

Selection reference:

NN3009 KTN/VQ497 (taper bore polyamide cage + stabilized heat treatment, medium-heavy duty spindles with adjustable preload)

NN3009 TN/VQ497 (straight bore polyamide cage, spindle modules with spacer preset preload)

NN3009 KTNHA/VQ497 (taper bore reinforced polyamide cage for sustained higher speed)

NN3009 KTN/VQ497/SP (taper bore + stabilized heat treatment + SP super precision for high-end grinder spindles)

7009 angular contact ball bearings: Paired to carry spindle axial loads.

3 Core Performance Advantages

1. Double-row roller design delivers significantly higher radial load capacity and rigidity compared to same-size single-row cylindrical roller bearings, suitable for medium-heavy cutting applications.

2. 1:12 tapered bore allows flexible preload tuning during assembly to match various cutting loads and speed ranges.

3. TN polyamide roller-guided cage is lightweight with low friction loss, effectively restraining temperature rise at moderate high speeds.

4. VQ497 stabilized heat treatment suppresses dimensional creep during long continuous operation and maintains consistent accuracy for mass production.

5. Separable inner and outer rings simplify disassembly, maintenance and bearing replacement for machine tool spindle assemblies.

4 Typical Application Fields

4.1 Medium-Heavy Duty Precision Metal-Cutting Machine Tool Spindles

Precision CNC lathe spindles, cylindrical grinder spindles, hob grinder spindles, heavy-duty turn-mill spindle units

4.2 Continuous mass-production rotary units requiring long-term dimensional stability

Batch grinding line spindles, precision roll supports, heavy-duty precision dividing heads

4.3 Rotary machinery with substantial radial load, priority on rigidity, requiring adjustable preload and non-stop long-term operation

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

Precision bearing assembly shall be performed in clean, dust-free constant-temperature workshop. All mating components must be thoroughly cleaned from chips and contaminants. Apply uniform axial preload via hydraulic nut on tapered bore inner ring; striking bearing face is forbidden. Preload magnitude must be strictly controlled to avoid sustained overheating. Conduct extended no-load temperature run-in after assembly. Shaft journal and housing bore geometric tolerances should meet P4 or higher precision class. Observe TN cage temperature limit to avoid long-term over-temperature operation.

5.2 Selection Guidance

Medium-heavy cutting, adjustable preload, continuous mass production → NN3009 KTN/VQ497

No on-site preload adjustment needed, spacer preset preload design → NN3009 TN/VQ497

Continuous higher operating speed required, reinforced cage needed → NN3009 KTNHA/VQ497

Higher rotational precision for finishing & grinding equipment → NN3009 KTN/VQ497/SP

Significant axial load exists: Combine this bearing with matched 7009 series precision angular contact ball bearings.

5.3 Lubrication Maintenance Instruction

No lubricant pre-filled at factory. Heavy-duty high-speed spindle grease for medium-low speed; oil-air lubrication recommended for higher speed. Long-term oil bath lubrication is not advised. Target steady-state temperature rise ≤28K; avoid continuous temperature over 120°C for TN polyamide cage. Inspect preload setting and lubrication supply if temperature rises persistently and abnormally.

5.4 Environmental Application Notes

No built-in seals. Spindle assembly shall be equipped with oil seals or labyrinth seals to prevent coolant and dust ingress. Long-term axial load and shock loads are prohibited; shock indentations permanently destroy rotational precision. VQ497 variant provides improved resistance against dimensional drift compared to standard bearings, yet frequent severe thermal cycling should still be avoided.

6 Fault Identification

Common failure modes: Abnormal operating temperature rise, gradual increase of spindle radial runout, periodic abnormal noise, raceway impact indentations, stress spalling on roller faces, progressive accuracy drift after long runtime. Stop equipment immediately once accuracy declines obviously or continuous abnormal noise occurs. Bearings with damaged raceways or rollers cannot be repaired and require complete replacement.