1 Model Information & Technical Parameters

Model：NN 3010 KTN/SPW33

Dimensions

Bore d：50 mm

Outer diameter D：80 mm

Width B：30 mm

Bore type: 1:12 tapered bore

Outer ring feature: W33 annular oil groove with lubrication holes

Accuracy class: SP precision grade

Code Explanation

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

3010: Size series 30, size code 10, nominal bore 50 mm, medium cross-section balancing radial rigidity and limiting speed

K: 1:12 tapered bore. Inner ring expands radially under axial tension from lock nut for adjustable preload during assembly

TN: Solid polyamide roller-guided cage; continuous operating temperature ≤120°C

SP: Precision accuracy grade, tighter dimensional tolerance and rotational accuracy above standard class

W33: Annular oil groove and through lubrication holes on outer ring, compatible with external centralized oil supply

Load Characteristics

Mainly withstand bidirectional radial loads. Axial load capacity is limited. Cannot bear continuous axial cutting force independently, must be combined with precision angular contact ball bearings. Separable construction with double-row steel rollers and TN polyamide cage. W33 oil path suits centralized lubrication. SP grade strictly controls dimensional and runout tolerance to guarantee spindle accuracy.

Limiting speed: Stable performance under medium and high speed; circulating oil or oil-air lubrication recommended.

Pre-grease: No pre-filled lubricant, apply lubricant according to lubrication system specification during installation.

Logistics & Industry Codes

Net weight：0.21 kg

eClass code：23-05-09-01

UNSPSC code：31171505

Suffix Explanation

NN: Double row cylindrical roller bearing, ribless outer ring, separable rings. Higher radial rigidity and load rating than single-row cylindrical roller bearings of equivalent size, widely used for spindle radial support.

3010: Medium cross-section Series 30 with balanced rigidity, general specification for various precision machine tool spindle units.

K: 1:12 tapered bore. Preload can be flexibly set via hydraulic or lock nut expansion, suitable for light-to-medium load finishing.

TN: Polyamide roller-guided cage with low friction and low temperature rise. TNHA high-temperature cage available for sustained high-temperature operation.

SP: Precision grade with stricter geometric tolerance, radial and axial runout standard, ideal for finishing equipment demanding stable machining accuracy.

W33: Outer ring with oil groove and holes for external centralized lubrication, continuously delivering lubricant to rolling contact zone for long-term continuous operation.

Important reminder: Cannot bear axial load independently. Match with precision angular contact ball bearings. Continuous temperature above 120°C is forbidden for TN cage. Ensure housing oil passages align with W33 holes without blockage. SP precision bearings demand strict assembly cleanliness and fit tolerance. Preload must be precisely controlled; excessive preload leads to higher temperature and accuracy degradation. Hammer assembly prohibited; use hydraulic nut for uniform pressing.

Alternative variants:

NN3010 KTN/W33 (standard precision, outer ring oil groove)

NN3010 KTN/SPW33 (SP precision grade + W33 oil groove)

NN3010 KTN/UPW33 (UP ultra-precision grade + W33 oil groove)

NN3010 KTNHA/SPW33 (high-temperature cage + SP grade + W33 oil groove)

2 Structure & Operating Characteristics

NN 3010 KTN/SPW33 is SP precision grade double row cylindrical roller bearing with outer ring lubrication design. Double-row roller arrangement provides high radial rigidity. The 1:12 tapered bore allows flexible preload adjustment to balance low heat generation at high speed and rigidity during cutting. The W33 oil groove and holes match circulating centralized lubrication systems to continuously remove friction heat. SP precision class controls bearing runout tightly to maintain stable spindle rotational accuracy. Separable rings simplify spindle disassembly and maintenance.

Selection guide:

NN3010 KTN/SPW33 (taper bore TN cage, SP precision, W33 lubrication for universal precision machining spindles)

NN3010 KTN/W33 (standard precision with outer ring oil groove, economical cutting spindles)

NN3010 KTNHA/SPW33 (precision spindles for long-hour continuous high-temperature production)

NN3010 KTN/UPW33 (ultra-precision machining equipment requiring superior rotational accuracy)

Recommended matching bearings: 7010 / 7210 series SP grade precision angular contact ball bearings for matched load and accuracy of complete spindle.

3 Core Performance Advantages

1. SP precision standard with tightly controlled dimensional tolerance and rotational runout, minimizing spindle rotation error and improving workpiece dimensional accuracy and geometric tolerance.

2. W33 annular oil groove and lubrication holes compatible with external centralized oil-air or circulating oil lubrication, enhanced heat dissipation for non-stop long-time production.

3. NN double-row roller layout delivers higher radial rigidity and load capacity than single-row cylindrical roller bearings with identical bore size, balancing rigidity and rotational smoothness.

4. 1:12 tapered bore enables flexible on-site preload adjustment to adapt to multiple finishing processes, better adjustability than fixed-preload straight bore solutions.

5. Lightweight TN polyamide roller-guided cage reduces friction loss and controls temperature rise under medium-high speed; separable inner and outer rings facilitate inspection and replacement.

4 Typical Application Fields

4.1 Spindles of medium & small precision CNC equipment

Precision CNC lathes, vertical machining centers, turn-mill composite machine finishing spindles requiring stable machining accuracy and equipped with centralized oil-air or circulating oil lubrication

4.2 General precision grinding machine spindles

Spindle units for internal & cylindrical grinders, surface grinders with continuous operation, constant oil supply and high requirement on spindle rotational accuracy

4.3 High-end precision rotary mechanisms requiring adjustable preload, circulating lubrication and stable radial precision

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

SP precision bearings should be assembled in constant-temperature dust-free clean workshops. Completely remove chips, dust and oil from shafts, housings and spacers. Fit tolerances of shaft journal and housing bore shall comply with precision bearing standards. Align housing oil passages with bearing W33 lubrication holes to avoid blockage. Apply preload evenly to tapered bore inner ring via hydraulic nut; hammering bearing faces is prohibited. Preload travel must be strictly monitored; excessive preload increases temperature and worsens accuracy. After assembly, conduct gradual speed-up and no-load run-in test for temperature and accuracy inspection. Observe the 120°C temperature limit for TN cages.

5.2 Selection Guidance

Precision finishing, centralized circulating lubrication, stable rotational accuracy required → NN3010 KTN/SPW33

Centralized lubrication, moderate accuracy demand, cost control → NN3010 KTN/W33

Non-stop long-hour machining, high ambient operating temperature → NN3010 KTNHA/SPW33

Ultra-precision machining, top-level rotational accuracy target → NN3010 KTN/UPW33

For significant axial loads: Combine this bearing with SP grade 7010 / 7210 angular contact ball bearings.

5.3 Lubrication Maintenance Instruction

No lubricant pre-filled at factory. Centralized oil-air lubrication or low-pressure circulating oil lubrication is recommended to maximize the benefits of W33 oil path. Long-term simple grease lubrication is not preferred. Maintain steady-state temperature rise below 25K. Avoid continuous temperature exceeding 120°C for TN polyamide cages. Regularly monitor oil supply pressure, oil passage status, spindle accuracy and vibration. Investigate lubricant contamination, preload decay or particle intrusion if accuracy drops continuously.

5.4 Environmental Application Notes

No integrated seals. Install oil seals or labyrinth seals on spindle assembly to block coolant and grinding dust. Rolling surfaces of precision bearings are sensitive to hard contaminants; tiny particles easily lead to accuracy loss and raceway damage. Long-term shock loads and sustained axial loads are forbidden. Minimize frequent sharp thermal cycling to maintain bearing dimensional stability. Periodically inspect W33 lubrication holes to prevent blockage leading to local overheating.

6 Fault Identification

Common failure modes: Enlarged workpiece dimensional fluctuation, out-of-tolerance geometric accuracy, abnormal spindle temperature rise, periodic abnormal rotation noise, local overheating caused by blocked oil holes, indentations or fatigue spalling on raceways, roller end face wear. Stop equipment immediately when machining accuracy cannot be recovered or continuous abnormal noise occurs. Bearings with permanent damage on raceways or rollers cannot be repaired and require complete replacement.