1 Model Information & Technical Parameters

Model：NN 3010 KTN/VQ497

 

Basic Dimensions

Parameter Value Unit

Bore diameter (d) 50 mm

Outside diameter (D) 80 mm

Width (B) 23 mm

Inner ring flange diameter (d₁) 61.3 mm

Outer ring raceway diameter (E) 72.5 mm

Chamfer dimension (r₁,₂ min.) 1.0 mm

Chamfer dimension (r₃,₄ min.) 0.6 mm

Permissible axial displacement (s max.) 1.5 mm

Bore type Tapered 1:12 —

Tolerance class SP —

Radial internal clearance NSTD —

Performance Data

Parameter Value Unit

Dynamic load rating (C) 52.8 kN

Static load rating (C₀) 73.5 kN

Fatigue load limit (Pᵤ) 8.5 kN

Limiting speed – grease 11,000 r/min

Limiting speed – oil-air 13,000 r/min

Reference grease quantity (Gref) 2.7 cm³

Axial static stiffness (guideline) 1,040 N/µm

Operating temperature range -30 ~ +110 °C

Technical Attributes

Attribute Detail

Bearing type Super-precision double row cylindrical roller bearing

Series NN 30

Number of rows 2

Inner ring design Three flanges (integral ribs)

Outer ring design Flangeless

Cage material PA66 nylon injection moulded cage, roller centred

Roller material Bearing steel (chrome steel)

Ring material Bearing steel (chrome steel)

Seal type Open (no seals)

Bore type Tapered 1:12

Tolerance class SP

Radial clearance NSTD

Separable design Yes (inner and outer rings separable)

Logistics & Industry Codes

Parameter Value Unit

Net weight 0.383 kg

eClass code 23-05-09-01 —

UNSPSC code 31171505 —

Indicative carbon footprint 1.4 kg CO₂e

Suffix Full Explanation

Suffix Meaning

NN Double row cylindrical roller bearing, high precision series

30 Dimension series (ISO series 30)

10 Bore size code – 50 mm (10 × 5 = 50 mm)

K Tapered bore, taper 1:12

TN PA66 nylon injection moulded cage, roller centred

VQ497 SKF/VQ quality and tolerance grade code – indicates quality and tolerances other than standard

Important reminder: This model features a tapered bore (1:12) . During mounting, a lock nut or withdrawal sleeve is used to drive the bearing onto the tapered shaft journal, enabling precise adjustment of radial clearance or preload. The bearing is open-type without seals and requires external lubrication and sealing protection based on actual operating conditions. Operating temperature range: -30°C to +110°C. The separable design allows independent mounting of inner and outer rings, facilitating assembly and maintenance. The VQ497 suffix represents specific quality and tolerance grade requirements. The three-flange inner ring and flangeless outer ring allow the bearing to accommodate axial displacement in both directions (max. 1.5 mm), effectively compensating for thermal expansion.

 

2 Structure & Operating Characteristics

The NMT NN 3010 KTN/VQ497 is a super-precision double row cylindrical roller bearing from the NN 30 series, specifically developed for high-precision, high-rigidity applications such as machine tool spindles. This series achieves a unique balance between load carrying capacity, rigidity and speed.

 

Double row roller design is the core structural feature. Two rows of rollers arranged in parallel distribute loads more evenly across a wider area, significantly increasing the contact area between rollers and raceways. Compared to single row bearings, the double row design offers higher load capacity and rigidity. The line contact between cylindrical rollers and raceways provides high radial load capacity, enabling the bearing to accommodate heavy loads and impact loads while also supporting high-speed rotation.

 

Three-flange inner ring and flangeless outer ring design is another key feature. The inner ring features three integral ribs (flanges) while the outer ring has no flanges, allowing the bearing to accommodate axial displacement in both directions. In applications with significant thermal expansion such as machine tool spindles, thermal elongation of the shaft and housing can be compensated through internal axial displacement, with maximum permissible axial displacement of 1.5 mm.

 

Separable design enables independent mounting of inner and outer rings, which is particularly convenient in interference fit applications – one ring can be mounted first, then the other assembled, greatly simplifying assembly and disassembly.

 

PA66 nylon injection moulded cage (TN suffix) ensures precise roller positioning and stability at high speeds. PA66 material offers excellent wear resistance and low friction characteristics, effectively reducing heat generation and energy consumption. The cage prevents cylindrical rollers from contacting each other, enabling controlled motion of rolling elements with lower friction, thus achieving higher speeds and reduced heat generation.

 

Tapered bore (1:12) design enables precise radial clearance or preload adjustment through axial advancement during mounting, critical for optimizing spindle system rigidity and accuracy.

 

SP tolerance class is the hallmark of NMT super-precision bearings. SP class bearings ensure extremely high running accuracy and low vibration levels, meeting high-precision machining requirements.

 

VQ497 suffix represents SKF/VQ quality and tolerance grade code, indicating quality and tolerances other than standard, ensuring consistency and reliability in critical applications.

 

3 Core Performance Advantages

1. Extremely high radial load capacity. Double row roller design and cylindrical roller line contact structure enable the bearing to withstand very high radial and impact loads. Dynamic load rating reaches 52.8 kN; static load rating reaches 73.5 kN.

 

2. Superior system rigidity. The unique double row compact configuration of the NN 30 series provides exceptionally high radial stiffness (axial static stiffness up to 1,040 N/µm), making it ideal for precision spindle systems.

 

3. Bidirectional axial displacement compensation. The three-flange inner ring and flangeless outer ring design allow the bearing to accommodate axial displacement in both directions during operation, with maximum permissible axial displacement of 1.5 mm, effectively compensating for thermal expansion.

 

4. Super-precision running accuracy. SP tolerance class ensures low vibration, low noise and low heat generation, meeting high-precision machining requirements.

 

5. VQ497 quality grade – reliable assurance for demanding conditions. The VQ497 suffix represents quality and tolerances other than standard, ensuring consistency and reliability in critical applications.

 

6. Tapered bore mounting with precisely adjustable clearance. 1:12 tapered bore enables precise radial clearance or preload adjustment through axial advancement during mounting, optimizing system rigidity.

 

7. Separable design for easy assembly and maintenance. Inner and outer rings can be mounted independently, particularly suitable for complex assembly conditions requiring interference fit.

 

8. Low friction, high efficiency and extended service life. Advanced materials and manufacturing techniques ensure minimal friction, reduced heat generation and extended service life.

 

4 Typical Application Fields

4.1 Machine Tool Spindles

Machining center spindles (horizontal and vertical), turning center spindles, milling spindles – the combination of high rigidity, high accuracy and high speed is a perfect match.

 

4.2 Precision Grinding Machines

External cylindrical grinder spindles, internal grinder spindles – extremely high radial load capacity and running accuracy ensure machining quality.

 

4.3 Aerospace Engines and Gas Turbines

Aircraft engine main shafts, gas turbine rotor supports – high strength and reliability meet aerospace requirements.

 

4.4 High-Performance Automotive and Racing

High-performance automotive transmissions, racing gearboxes, high-speed drive units.

 

4.5 Electric Motors and Generators

Large and medium electric motors, generators – stable performance under heavy loads and high speeds.

 

4.6 Industrial Machinery and Automation

Gearboxes, rolling mills, vibrating screens, lifting and transport machinery; robotics and automation system rotary supports.

 

5 Assembly Specifications & Usage Guidelines

5.1 Pre-installation Inspection

Verify model and specifications match design requirements. Inspect bearing appearance to ensure no damage, corrosion or foreign matter. Check shaft taper (1:12) and dimensional accuracy against design specifications. Prepare appropriate mounting tools such as lock nuts or hydraulic nuts.

 

5.2 Installation Procedure

This bearing features a tapered bore (1:12) . During mounting, the bearing must be driven onto the tapered shaft journal. Use a lock nut or hydraulic nut to apply axial advancement force, precisely adjusting radial clearance by controlling advancement distance. Never apply force through rolling elements or cage. Monitor radial clearance changes throughout installation until the target clearance value is achieved. The separable design allows independent mounting of inner and outer rings.

 

5.3 Clearance Adjustment Instructions

Radial clearance of tapered bore bearings decreases as axial advancement increases. During mounting, use feeler gauges or dial indicators to monitor clearance changes, ensuring clearance is adjusted to the design target. Maximum permissible axial displacement is 1.5 mm.

 

5.4 Lubrication Maintenance

This model comes without pre-filled grease – lubricant must be added during installation based on operating conditions. Grease limiting speed is 11,000 r/min; oil-air limiting speed is 13,000 r/min. Reference grease quantity is 2.7 cm³. High-quality spindle grease or circulating oil is recommended. Open construction requires reliable sealing protection at the equipment level. Establish regular lubrication replenishment schedule; dry running is strictly forbidden.

 

5.5 Environmental Considerations

Operating temperature range: -30°C to +110°C. As this bearing is open construction, in dusty environments or coolant splash conditions, labyrinth seals or contact seals must be provided at the equipment level. The bearing itself does not carry axial loads; axial displacement (max. 1.5 mm) is accommodated by the external structure.

 

6 Fault Identification

Common failure modes: Roller or raceway fatigue pitting, abnormal operating noise increase, significant rotation resistance increase, excessive temperature rise, seizure caused by poor lubrication. If cage deformation or rolling element damage occurs, replace the entire bearing assembly – repair and reuse are not allowed. Regularly monitor bearing temperature and vibration for early detection of abnormalities.