1 Model Information & Technical Parameters

Model：NN 3016 TN/SPW33

Dimensions

Bore d：80 mm

Outer diameter D：125 mm

Width B：34 mm

Bore type: Straight cylindrical bore

Radial clearance: C1 minimal internal clearance

Accuracy class: SP precision grade

Structure: NN double row design, inner ring with three ribs, ribless outer ring allowing axial floating

Outer ring flange: None

Lubrication groove: W33 circumferential groove and oil holes on outer ring, supports on-line re-lubrication during operation

Seal: Open design, no seals

Surface coating: Uncoated

Pre-lubrication: No lubricant supplied from factory

Code Explanation

NN: Double row cylindrical roller bearing, three ribs on inner ring, ribless outer ring with axial floating capacity to compensate spindle thermal elongation, mainly for radial loads with excellent rigidity.

3016: Size series 30 wide cross-section spindle bearing with high load capacity.

TN: Standard non-metallic roller-guided cage, stable performance under medium-high speed conditions.

SP: Precision accuracy grade, dimensional tolerance and rotational runout meet requirements of general high-precision machining spindles.

W33: Circumferential lubrication groove and through oil holes machined on outer ring, compatible with centralized lubrication systems for continuous lubricant supply during machine operation.

Load & Speed Data

Basic dynamic load rating Cr：119 kN

Basic static load rating C0r：186 kN

Permissible speed, grease lubrication：7 000 r/min

Permissible speed, oil-air lubrication：8 000 r/min

Material & Additional Properties

Rolling element material: Bearing steel

Indicative carbon footprint：5.6 kg CO₂e

Net weight：1.5 kg

eClass code：23-05-09-01

UNSPSC code：31171505

Suffix Explanation

NN: Double row cylindrical roller bearing. Three ribs on inner ring guide two roller rows; ribless outer ring floats axially to absorb thermal expansion, designed primarily for radial loads.

3016: Series 30 wide-section spindle bearing with extended contact length, excellent performance under heavy loads.

TN: Standard non-metallic roller-guided cage with mature stable structure suitable for continuous medium-high speed operation.

SP: Precision accuracy grade, widely adopted for standard high-precision cutting and grinding spindles with favorable cost performance.

W33: Circumferential lubrication groove and penetrating oil holes on outer ring, capable of connecting centralized lubrication pipelines to realize continuous grease or oil supply without machine shutdown.

C1 clearance: Minimal radial internal clearance, suitable for lightly preloaded medium-high speed continuously running spindles to suppress vibration and stabilize workpiece surface finish.

Important reminder: This straight bore NN-type double row cylindrical roller bearing features fixed preload without on-site adjustment via lock nut. Equipped with standard W33 lubrication channels on outer ring, perfectly suitable for 24/7 mass production with centralized lubrication. NN floating outer ring only bears radial loads and cannot sustain axial force; paired angular contact ball bearings are required for spindle axial positioning. Open bearing without built-in seals; high-performance labyrinth seals or oil seals must be installed on housings to block coolant and dust. No pre-filled grease upon delivery. Ideal for continuously running automated production lines and precision machining spindles requiring online uninterrupted lubricant supply.

Alternative variants:

NN3016 TN/SP (straight bore, SP grade, no W33 groove, intermittent precision spindles, re-greasing only during shutdown)

NN3016 TN/UPW33 (straight bore, UP ultra-precision grade, W33 groove, ultra-precision continuous mass production spindles)

NN3016 KTN/SPW33 (1:12 tapered bore, SP grade, W33 groove, continuous production spindles allowing on-site preload adjustment)

NN3016 KTN/SP (1:12 tapered bore, SP grade, no lubrication groove, adjustable preload for intermittent machining spindles)

2 Structure & Operating Characteristics

NN 3016 TN/SPW33 is an SP precision grade double row cylindrical roller bearing with C1 minimal radial clearance, standard TN non-metallic cage, bearing steel rolling elements and straight cylindrical bore. W33 circumferential lubrication groove and oil holes are integrated on outer ring. Two rows of steel rollers share loads simultaneously to boost radial rigidity. The NN ribless outer ring slides freely in axial direction to compensate spindle thermal expansion and eliminate extra axial stress caused by temperature rise.

Core advantages are fixed preload straight bore structure + W33 outer ring on-line lubrication channel. Straight cylindrical bore enables convenient assembly with fixed preload after installation, ideal for mass production equipment with mature processes that rarely require preload modification. SP precision grade satisfies accuracy demands of most standard precision machining. The W33 oil supply structure connects centralized lubrication systems to replenish lubricant without shutdown, perfectly matching long-term continuous automated production scenarios.

Selection guide:

NN3016 TN/SPW33 (straight bore, TN cage, SP precision, W33 groove, continuous mass production, on-line lubrication, fixed preload)

NN3016 TN/SP (straight bore, TN cage, SP precision, no lubrication groove, intermittent production, offline re-greasing)

NN3016 TN/UPW33 (straight bore, TN cage, UP ultra-precision, W33 groove, mirror-grade continuous finishing spindles)

NN3016 KTN/SPW33 (1:12 tapered bore, TN cage, SP precision, W33 groove, continuous production, on-site preload adjustable)

Recommended matching bearing: Paired 7016 SP angular contact ball bearings to bear all axial loads and realize bidirectional spindle axial positioning.

3 Core Performance Advantages

1. Double-row bearing steel roller arrangement delivers powerful radial load capacity and superior spindle rigidity, suitable for medium-high speed precision cutting and continuous grinding.

2. NN-type wide-section double-row structure achieves uniform load distribution and better anti-tilting performance than single row cylindrical roller bearings.

3. Straight cylindrical bore simplifies assembly and maintains stable preload, fit for standardized mass spindle assembly.

4. Mature TN non-metallic cage ensures stable and reliable performance under continuous medium-high speed operation.

5. SP precision standard combined with C1 minimal radial clearance guarantees stable rotary accuracy, restrains machining chatter marks and ensures consistent workpiece surface quality.

6. Axially floating outer ring automatically compensates spindle thermal elongation, prevents extra internal bearing stress and extends service life.

7. Standard W33 lubrication groove and oil holes directly adapt to centralized oil-air and grease lubrication systems, supporting on-line lubricant replenishment during non-stop production.

4 Typical Application Fields

4.1 Spindles of precision CNC cylindrical & internal grinding machines on automated production lines

24-hour continuous operation with centralized lubrication system for stable mass precision grinding

4.2 Precision turning spindle units for batch component machining

Stable standardized processes without frequent spindle preload adjustment, priority on long-term operational stability

4.3 High-precision general grinding equipment and automated tool grinding spindles

Long non-stop operation requiring continuous on-line grease replenishment

4.4 Auxiliary spindles of medium & small precision machining centers, rotary spindles for automated tooling fixtures

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

SP precision bearings should be assembled in clean workshops with dust control. Thoroughly clean contaminants on shaft journals, housing bores and spacer contact surfaces. Straight cylindrical bore adopts interference fit for press fitting; uniform pressing is required and violent hammering is forbidden. Oil supply ports shall be reserved inside bearing housings and aligned with W33 oil holes on outer ring. High-performance sealing must be installed on machine housings to block coolant and dust ingress. This NN-type bearing cannot withstand axial loads; paired SP grade angular contact bearings are mandatory for spindle axial positioning. Avoid long-term continuous shock loads.

5.2 Selection Guidance

Continuous automated mass production, fixed preload, centralized on-line lubrication → NN3016 TN/SPW33

Intermittent production, fixed preload, re-greasing only during shutdown → NN3016 TN/SP

Continuous production, ultra-high rotary accuracy required, on-line lubrication needed → NN3016 TN/UPW33

Continuous mass production requiring flexible on-site preload adjustment → NN3016 KTN/SPW33

Important notice: NN double row structure is designed for radial loads only. Sustained axial force leads to edge stress concentration, roller scuffing and premature fatigue spalling. Ensure W33 oil holes on outer ring align with housing lubrication channels during assembly; misalignment will block lubricant flow and result in overheating failure.

5.3 Lubrication Maintenance Instruction

No lubricant pre-filled at factory. Both grease lubrication and oil-air lubrication are applicable; lubricant can be replenished on-line via outer ring W33 channels. Select long-life grease or oil suitable for medium-high speed working conditions and set automatic periodic lubrication cycles. Continuously monitor bearing temperature, vibration values and machining quality; inspect lubrication pipeline smoothness and lubrication cycle settings once abnormal temperature rise occurs.

5.4 Environmental Application Notes

Open structure without built-in seals; high-performance labyrinth seals or oil seals on bearing housings are compulsory. Rolling contact surfaces are extremely sensitive to hard particles; foreign contaminants easily cause raceway pitting and damage rotary accuracy. TN cage fits regular continuous medium-speed working conditions; avoid long-term exposure to extreme high temperature which accelerates cage aging and damage.

6 Fault Identification

Common failure modes: periodic chatter marks on workpieces, increased fluctuation of machining dimensions, continuous abnormal temperature rise of spindle, periodic rotational noise, roller scuffing, raceway fatigue pitting. Typical failures for straight bore bearings: persistent overheating caused by excessive assembly interference; outer ring creep wear due to insufficient interference; interrupted lubrication resulting from blocked W33 oil holes; uneven abrasion of two roller rows induced by unexpected axial loads. Shut down equipment immediately upon continuous accuracy degradation, abnormal temperature rise or abnormal noise. Bearings with permanent damage to raceways, rolling elements or cage cannot be repaired and need complete replacement.