1 Model Information & Technical Parameters

Model：NN 3013 TN/SPW33

Dimensions

Bore d：65 mm

Outer diameter D：100 mm

Width B：26 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, double sets of rollers

Outer ring flange: None

Seal: Open design, no seals

Surface coating: Uncoated

Pre-lubrication: No lubricant supplied from factory

Re-lubrication feature: W33 circumferential lubrication groove & radial oil holes on outer ring, supporting continuous on-line re-lubrication

Code Explanation

NN: Double row cylindrical roller bearing, three ribs on inner ring, ribless outer ring. Two rows of rollers share radial loads simultaneously.

3013: Size series 30 medium cross-section spindle bearing with outstanding load capacity.

TN: Solid polyamide non-metallic roller-guided cage, low friction and controllable temperature rise under continuous high-speed operation.

SP: Precision accuracy grade with strictly controlled rotational runout for precision machine tool spindle applications.

W33: Outer ring machined with circumferential lubrication groove and oil holes for continuous on-line lubricant supply.

Load & Speed Data

Basic dynamic load rating Cr：76.5 kN

Basic static load rating C0r：116 kN

Permissible speed, grease lubrication：9 000 r/min

Permissible speed, oil-air lubrication：10 000 r/min

Material & Additional Properties

Material: Bearing steel

Indicative carbon footprint：2.5 kg CO₂e

Net weight：0.686 kg

eClass code：23-05-09-01

UNSPSC code：31171505

Suffix Explanation

NN: Double row cylindrical roller bearing. Three ribs on inner ring constrain two roller rows; ribless outer ring. Radial rigidity and load capacity are much higher than single row bearings. Limited bidirectional axial locating capacity allows moderate axial loads.

3013: Series 30 spindle-dedicated double row bearing. Balanced cross-section optimizes both load capacity and speed performance, widely used for CNC spindle support.

TN: Polyamide cage, lightweight non-metallic structure with low friction coefficient, ensuring stable temperature and low noise during long continuous operation.

SP: Precision accuracy grade. Dimensional tolerance, radial and axial runout are tighter than standard bearings to maintain stable machining precision under high speed and heavy loads.

C1 clearance: Minimal radial internal clearance, matched for lightly preloaded spindle systems to suppress vibration and improve workpiece surface finish.

W33: Circumferential groove and radial oil holes on outer ring, easy to connect with housing lubrication circuits and enable uninterrupted re-lubrication without machine shutdown, suitable for 24-hour mass production.

Important reminder: This straight-bore NN-type double row cylindrical roller bearing has no tapered bore. Clearance and preload cannot be adjusted on-site after assembly, preload is defined by fixed interference fit between shaft journal and inner ring. The W33 groove perfectly matches automatic continuous lubrication systems. Double-row design provides high rigidity and load capacity, yet limiting speed is lower than single row cylindrical roller bearings of equal dimensions. Moderate bidirectional axial loads can be sustained; matched angular contact ball bearings are recommended for heavy axial forces. Open bearing without built-in seals; labyrinth seals or oil seals must be installed on housings to block coolant and dust ingress. No pre-filled grease upon delivery; lubricant should be filled during assembly. Never strike inner or outer ring directly during assembly to prevent indentations on raceways and rollers.

Alternative variants:

NN3013 KTN/SPW33 (1:12 tapered bore, on-site preload adjustable, with W33 groove)

NN3013 TN/SP (straight bore, no W33 groove, only for one-time greasing and intermittent production)

NN3013 TNHA/SPW33 (high-temperature polyamide cage for continuous high-temperature production lines)

NN3013 TN/UPW33 (UP ultra-precision grade for ultra-high precision mirror machining spindles)

2 Structure & Operating Characteristics

NN 3013 TN/SPW33 is an SP-grade precision double row cylindrical roller bearing with C1 minimal radial clearance, TN polyamide cage, straight cylindrical bore and outer ring equipped with W33 lubrication groove. Symmetric double-row roller layout delivers significantly improved radial load capacity and rigidity compared with equivalent single row bearings, together with limited axial locating ability, making it a mainstream radial support for heavy-duty precision machine tool spindles. The NN design with three inner ring ribs restricts roller axial movement; thermal elongation compensation is inferior to floating N-type single row bearings.

The core advantage lies in the W33 outer ring lubrication channel, which connects to automatic oil supply circuits and enables continuous grease or oil-air replenishment, ideal for non-stop mass production lines. The straight bore relies on fixed interference for preload; high machining tolerance requirements apply to shaft journals and no on-site tuning is available after mounting. Combined C1 minimal clearance and precision manufacturing tolerances reduce rotary vibration under high speed and heavy cuts, stabilizing dimensional accuracy in heavy finishing operations.

Selection guide:

NN3013 TN/SPW33 (straight bore with W33 groove, SP C1 clearance, fixed preload, heavy-duty spindles with continuous on-line lubrication)

NN3013 TN/SP (straight bore without lubrication groove, one-time grease filling for intermittent processing)

NN3013 KTN/SPW33 (1:12 tapered bore, adjustable preload plus continuous lubrication)

NN3013 TNHA/SPW33 (heat-resistant cage for production lines with elevated ambient temperature)

NN3013 TN/UPW33 (ultra-precision grade for heavy-duty high-precision grinding spindles)

Recommended matching bearing: Paired 7013 SP angular contact ball bearings to carry primary axial loads.

3 Core Performance Advantages

1. NN double-row roller arrangement achieves high radial load capacity and extreme rigidity, suitable for heavy cutting and heavy-load finishing processes.

2. W33 circumferential outer ring groove and oil holes enable connection with automatic lubrication systems for continuous lubricant replenishment during machine operation.

3. TN polyamide non-metallic cage guarantees stable rotation and low friction, offering excellent temperature control during long continuous operation.

4. SP precision standard combined with C1 minimal radial clearance delivers tight control over rotational runout, mitigates vibration under high speed and heavy loads and stabilizes machining accuracy.

5. Limited bidirectional axial locating capacity simplifies structural design of spindle support systems.

6. Bearing steel construction ensures stable contact performance of raceways and rollers with consistent performance during prolonged continuous operation.

4 Typical Application Fields

4.1 Vertical machining centers and small gantry machining center spindle units

Heavy cutting, automated mass production lines with automatic continuous lubrication systems

4.2 CNC cylindrical grinders, jig grinders and roll grinder precision spindles

Heavy-duty precision grinding requiring high rigidity, continuous oil supply and stable long-term operation

4.3 Precision CNC lathes and turn-mill composite heavy-duty spindles

Mass continuous finishing with substantial radial cutting loads on spindles

4.4 Precision high-speed heavy-duty rotary components for automated production lines

High-precision rotating machinery operating 24/7 and equipped with automatic lubrication systems

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

SP precision bearings should be assembled in constant-temperature dust-free clean workshops. Thoroughly remove contaminants on shaft journals, housing bores and spacer contact surfaces. Preload is established via interference fit for straight bore bearings. No preload adjustment possible after assembly, machining accuracy of shaft journals directly determines internal clearance and preload status. Align W33 outer ring groove with housing oil passages to ensure smooth lubricant delivery to rolling contact zones. After assembly, implement low-speed gradual speed-up no-load running-in. Reliable sealing must be installed on machine housings to prevent coolant and dust from reaching rolling surfaces. Paired angular contact bearings are recommended to share axial loads under heavy axial working conditions.

5.2 Selection Guidance

Continuous mass production, automatic lubrication, fixed interference preload, no on-site adjustment needed → NN3013 TN/SPW33

Intermittent production, no continuous on-line oil supply, one-time grease filling during assembly → NN3013 TN/SP

On-site preload tuning required together with automatic lubrication circuit → NN3013 KTN/SPW33

Production lines with high ambient temperature and non-stop operation → TNHA high-temperature cage version

Ultimate rotational accuracy, heavy-duty high-precision mirror grinding → NN3013 TN/UPW33

Important notice: Straight bore design means preload cannot be adjusted after mounting. Shaft journal fit tolerance must be carefully calculated at the selection stage. Although limited axial loads can be accommodated, sustained heavy axial force easily causes edge stress concentration and roller end scuffing.

5.3 Lubrication Maintenance Instruction

No lubricant pre-filled at factory. Oil-air lubrication is recommended to achieve maximum permissible rotational speed; automatic circulating grease supply suits long continuous mass production. Continuous oil supply is realized via W33 outer ring channels. Regularly inspect oil passages for blockage to avoid localized overheating caused by insufficient lubrication. Continuously monitor bearing temperature and prevent prolonged overheating. Blocked oil channels and interrupted lubrication quickly lead to fatigue wear on rollers and raceways.

5.4 Environmental Application Notes

Open structure without built-in seals; labyrinth seals or oil seals on housings are compulsory. Raceways and rollers are extremely sensitive to tiny hard particles. Contamination amplifies vibration and rapidly deteriorates machining accuracy. Severe shock loads should be avoided to prevent indentations on rolling contact surfaces.

6 Fault Identification

Common failure modes: steadily rising vibration during heavy cutting, regular texture patterns on machined workpieces, continuous spindle temperature increase, periodic rotational noise, cage abrasion, roller end scuffing and raceway fatigue spalling, local overheating triggered by blocked W33 oil holes. Typical failures for straight bore double row bearings include excessive preload and persistent overheating due to over-tight shaft fit, or insufficient preload and degraded rotary accuracy caused by loose fit. Blocked lubrication channels and interrupted oil supply lead to local dry friction damage. Overloaded axial force results in uneven load sharing between two roller rows and premature fatigue of one side raceway. Shut down equipment immediately upon persistent abnormal noise or irreversible accuracy degradation. Bearings with permanent damage to raceways, rollers or cage cannot be repaired and need complete replacement.