1 Model Information & Technical Parameters

Model：NN 3006 KTN/SP

Dimensions

Bore d：30 mm

Outer diameter D：55 mm

Width B：19 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

3006: Size series 30, size code 06, nominal bore 30 mm

K: 1:12 tapered bore, preload adjustable by axial pushing of inner ring

TN: Solid polyamide cage, roller guided

/SP: Super precision spindle grade, higher accuracy than standard P4

Load Characteristics

Permitted load: Radial load only; axial load capacity negligible

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

Limiting speed: Polyamide cage brings lower friction and better high-speed performance than brass cage; limiting speed depends on lubrication, oil-air lubrication achieves higher speed than grease lubrication

Pre-grease: No pre-filled grease, lubricant added upon installation

Logistics & Industry Codes

Net weight：0.18 kg

Indicative carbon footprint：0.26 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; rollers confined by inner ring ribs.

K: 1:12 tapered bore. Axial locking expands inner ring radially for on-site preload adjustment, classic spindle configuration.

TN: Polyamide (nylon) cage, light weight, low friction and lower temperature rise; maximum continuous operating temperature limited.

/SP: Super precision grade, strictly controlled raceway geometry and rotational runout for finishing and grinding spindles.

Important reminder: Ribless outer ring cannot sustain axial force independently. Spindle must adopt matched precision angular contact ball bearings to bear axial load. Continuous operating temperature of polyamide cage should not exceed 120°C; brass cage version is recommended for high-temperature applications. Control preload accurately during tapered bore assembly; excessive preload causes overheating and seizure. Hammer impact installation prohibited; thermal mounting or hydraulic nut assembly recommended. Straight bore alternative: NN3006 TN/SP. Brass cage variant: NN3006 K/SP. General precision version: NN3006 KTN/P4. Higher precision: NN3006 KTN/UP.

2 Structure & Operating Characteristics

NN 3006 KTN/SP super precision double row cylindrical roller bearing adopts two parallel roller rows for high radial rigidity. The 1:12 tapered bore allows flexible preload tuning during assembly. TN polyamide cage reduces friction and temperature rise compared with brass cage, more suitable for high-speed spindles. SP ultra-precision machining minimizes rotational runout to stabilize finishing accuracy. Separable rings simplify spindle disassembly and maintenance.

Selection reference:

NN3006 KTN/SP (taper bore + polyamide cage + SP super precision, high-speed spindle with adjustable preload)

NN3006 TN/SP (straight bore polyamide cage SP grade, preset preload)

NN3006 K/SP (taper bore brass cage SP grade, higher temperature resistance)

NN3006 KTN/P4 (taper bore polyamide cage P4 grade, cost-effective general precision machinery)

NN3006 KTN/UP (taper bore polyamide cage UP ultra-precision for ultra-precise grinders)

7006 angular contact ball bearings: Paired to undertake spindle axial loads.

3 Core Performance Advantages

1. Double-row roller design offers high radial load capacity and outstanding radial rigidity to reduce spindle radial deflection.

2. 1:12 tapered bore enables precise preload adjustment during assembly to adapt to various cutting conditions and speed ranges.

3. TN polyamide cage delivers low friction, lower operating temperature and superior high-speed performance.

4. SP super precision grade ensures minimal rotational runout for high-precision cutting and grinding processes.

5. Separable inner and outer rings simplify disassembly, maintenance and replacement of spindle assemblies.

4 Typical Application Fields

4.1 High-speed Precision Machine Tool Spindle Units

Vertical machining center spindles, high-speed CNC lathe spindles, internal & external cylindrical grinder spindles

4.2 High-precision rotary equipment with adjustable preload and low heat priority

Precision gear grinding machines, high-speed precision dividing heads, CNC rotary tables

4.3 Medium-high speed rotary mechanisms with high radial rigidity, requiring on-site preload tuning and temperature control

5 Assembly Specifications & Usage Guidelines

5.1 Assembly Environment & Operation Standards

Assembly of precision bearings requires clean, dust-free workshop. All mating components must be thoroughly cleaned to eliminate chips and contaminants. Use hydraulic nut for uniform axial preloading on tapered bore inner ring; striking bearing face is forbidden. Strictly control preload stroke to avoid over-preheating. Perform no-load temperature run-in after assembly. Shaft journal and housing bore geometric tolerances must meet SP grade requirements. Observe temperature limit of polyamide cage and avoid prolonged over-temperature operation.

5.2 Selection Guidance

High-speed spindle, adjustable preload, priority on low operating temperature → NN3006 KTN/SP

Sustained high operating temperature, higher cage heat resistance required → NN3006 K/SP

No on-site preload adjustment, spacer-based preset preload → NN3006 TN/SP

Medium precision requirement, cost control target → NN3006 KTN/P4

Ultra-precision processing equipment with extreme accuracy demand → NN3006 KTN/UP

Significant axial load exists: Combine this bearing with matched 7006 series precision angular contact ball bearings.

5.3 Lubrication Maintenance Instruction

No lubricant pre-filled from factory. High-speed bearing grease for medium-low speed; oil-air lubrication preferred for high-speed spindles. Long-term oil bath lubrication is not recommended. Continuously monitor steady-state temperature rise, target ≤25K; polyamide cage should avoid continuous temperature above 120°C. Investigate preload and lubrication supply if temperature rises persistently.

5.4 Environmental Application Notes

No built-in seals. Spindle assembly must install oil seals or labyrinth seals to block coolant and dust ingress. Long-term axial load and shock loads are prohibited; shock indentations permanently destroy bearing precision. Avoid sustained high-temperature environment; switch to brass cage model under high temperature.

6 Fault Identification

Common failure modes: Abnormal temperature rise during operation, progressive increase of spindle radial runout, periodic abnormal noise, raceway indentations, roller fatigue spalling. Halt operation immediately once accuracy declines or continuous abnormal noise occurs. Bearings with damaged raceways or rollers cannot be repaired and need complete replacement.