Description
Authorized Channel Traceability — Every N 1008 KPHA/HC5SPVG271 we ship carries batch-level documentation tied to the manufacturer’s official distribution network, verified before dispatch.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | SKF N 1008 KPHA/HC5SPVG271 |
| Bearing Type | Single Row Cylindrical Roller Bearing |
| Bore Diameter (d) | 40 mm |
| Outside Diameter (D) | 68 mm |
| Width (B) | 15 mm |
| Weight | 0.250 kg |
| Bore Type | Tapered (1:12 taper) |
| Number of Rows | Single |
| Seal or Shield Type | Open |
| Precision Class | SP (Super Precision) |
| Origin | China |
Note: The suffixes PHA, HC5, and VG271 appear in the manufacturer’s designation string but require catalog confirmation for exact meaning — typically these relate to cage design, rolling element material, and special internal geometry respectively.
Application Suitability
| Industry | Typical Applications |
|---|---|
| Machine Tool Manufacturing | High-speed spindle nose bearing / grinding head quill support |
| Precision Equipment | Coordinate measuring machine rotary axis / optical indexing table |
| Heavy-duty Gearboxes | High-speed stage shaft support requiring minimal radial runout |
What Happens When a Spindle Bearing Suffix Goes Unchecked
A single missed suffix can turn a precision spindle into a vibration source within weeks.
I once watched a procurement team match a cylindrical roller order by the base number N 1008 alone, ignoring everything after the slash. The replacement was a standard bore, steel-cage, P0-grade unit. The spindle reached operating temperature in minutes, vibration analysis flagged cage chatter, and the hybrid ceramic specification was completely absent. The downtime cost dwarfed the bearing price. This SKF N 1008 KPHA/HC5SPVG271 cylindrical roller bearing carries a suffix string that encodes cage material, rolling element composition, clearance class, and precision grade — each character is load-bearing [NEED_CITE: bearing suffix designation system impact on application performance]. Counterfeit bearings now arrive with cloned QR codes and soft inner rings that pass casual visual inspection but fail under thermal stress, making suffix-level verification non-negotiable for spindle applications.
How This Bearing Aligns with Spindle Demands
Machine tool spindles demand sub-micron radial runout and thermal stability at sustained high speeds. The SKF N 1008 KPHA/HC5SPVG271 cylindrical roller bearing delivers SP-class dimensional and running accuracy, which sits between P4 and P2 in ISO 492 tolerance bands — tight enough for precision grinding heads without the cost premium of UP grade. We typically cross-check this designation against equivalent NSK and FAG super-precision cylindrical offerings, confirming that bore taper, cage type, and internal clearance all align before releasing the substitution recommendation.
Spindle Operating Conditions and Performance Boundaries
Spindle bearings face sustained radial loads at speeds that push lubrication films to their limits. The open configuration on this unit means external oil-air or oil-mist lubrication is mandatory — grease packing is not viable at these speed factors. Thermal growth of the shaft demands that the tapered bore be driven onto the mating seat with a controlled axial displacement to achieve the correct residual internal clearance [NEED_CITE: cylindrical roller bearing tapered bore mounting procedure and residual clearance]. Ambient temperature swings in the workshop further complicate the interference fit calculation, particularly when the spindle housing is cast iron and the shaft is alloy steel with different thermal expansion coefficients.
Decoding the Specification String
The K suffix confirms a 1:12 tapered bore, meaning the bearing must be driven axially onto a matching tapered journal or adapter sleeve — the drive distance directly sets the internal radial clearance, which governs both stiffness and thermal behavior. SP precision class mandates tighter bore and outside diameter tolerances than standard P6 or P5, plus controlled running accuracy on the inner ring raceway that directly affects workpiece surface finish in grinding operations. The cylindrical roller geometry itself — line contact between rollers and raceway — delivers high radial rigidity with low friction compared to ball bearings of equivalent envelope, though it cannot carry axial load. The open design eliminates seal drag but shifts contamination protection responsibility entirely to the machine’s external sealing arrangement.
The Hidden Cost of a Wrong-Specification Replacement
Installing a standard clearance CN bearing where the application requires C3 for thermal expansion results in preload buildup as the spindle heats up, accelerating roller and raceway wear until thermal seizure occurs. A bearing that passes visual inspection but carries a soft inner ring from unverified sourcing will spall under cyclic loading far earlier than ISO 281 L10 calculations predict. These failures rarely present as clean fatigue — ISO 15243 classifies them under mounting damage or material defects, and the warranty is void the moment traceability documentation is missing [NEED_CITE: ISO 15243 rolling bearing failure mode classification]. The real expense is unplanned spindle teardown, lost production shifts, and scrapped workpieces.
How We Source This Bearing Differently
Every unit we quote passes through authorized distributor channels with full batch traceability, not gray-market surplus of unknown provenance. We verify the QR code against the manufacturer’s official application before shipment and provide the Certificate of Conformity matched to the specific lot number. Our cross-reference database stores clearance class, cage material, and precision grade alongside the base designation — so when a maintenance engineer calls with an OEM equipment number, we match the full suffix string, not just N 1008. We also supply country-of-origin documentation formatted for import compliance, which eliminates customs delays for buyers in regions with strict rules of origin requirements.
Documentation & Authenticity
- Supplier Certificate of Conformity listing batch and lot number specific to this SP-precision shipment
- Third-party runout inspection report confirming bore and OD dimensional accuracy against ISO 492 SP tolerances
- QR code verification pathway confirmed active via the manufacturer’s official mobile application
- Country-of-origin certificate prepared for customs documentation on international shipments
- Material test certificate available for the bearing steel heat used in production
Storage, Handling & Mounting
- Keep the SKF N 1008 KPHA/HC5SPVG271 in original sealed packaging until the moment of mounting — early exposure to workshop humidity compromises the factory-applied corrosion inhibitor on this open-type bearing
- The tapered bore requires a hydraulic nut or controlled axial drive method; record the drive distance to confirm the correct residual clearance is achieved on the 1:12 taper seat
- Store horizontally on a vibration-free shelf — SP-precision raceways are sensitive to false brinelling from ambient vibration even before installation
- Use lint-free cleanroom gloves when handling the exposed rollers and raceways, as skin oils degrade the oil-air lubrication film at high spindle speeds
- Confirm the mating shaft taper angle and surface finish match the 1:12 specification before attempting press-on; a mismatched taper will leave the inner ring split or under-seated
Request a Quotation with Full Technical Review
Share your spindle operating parameters — speed range, radial load profile, lubrication method, and housing material — so we can confirm this designation matches your application requirements. If you are replacing an existing bearing, provide the OEM equipment number or the full marking string from the removed unit for cross-reference verification. We will return a quotation with lead time, batch availability, and the complete documentation package for your import process.
Frequently Asked Questions
Q: How can I verify the authenticity of an SKF super-precision bearing before installation?
A: Scan the QR code on the packaging using the manufacturer’s official mobile application — it should return the bearing designation, production batch, and manufacturing facility matching the markings on the bearing itself. Any mismatch between the app data and the physical markings is a red flag. We also supply the Certificate of Conformity with each shipment for independent verification.
Q: What does SP precision class mean compared to P4 or P5?
A: SP (Super Precision) sits between P4A and P2 in dimensional and running accuracy under ISO 492. It specifies tighter bore diameter tolerances, outside diameter tolerances, and inner ring running accuracy than P5 or P4 alone — critical for spindle applications where radial runout directly translates to workpiece surface finish errors.
Q: Can I substitute this bearing with another brand using only the base number N 1008?
A: No. The base number defines only the envelope dimensions and bearing type. The suffix string encodes tapered bore, cage material, precision class, and internal design variants. A cross-reference must match every suffix element — bore type, clearance class, cage type, and precision grade — or the replacement will not perform correctly in the spindle application.
Q: What are the mounting requirements for a tapered bore cylindrical roller bearing?
A: The 1:12 tapered bore must be driven onto a matching tapered journal or adapter sleeve using a hydraulic nut or controlled axial displacement method. The drive distance determines the internal radial clearance, which must be measured and recorded to ensure it falls within the application’s thermal expansion allowance. Induction heating of the inner ring is acceptable but must not exceed the tempering temperature of the bearing steel [NEED_CITE: cylindrical roller bearing tapered bore mounting clearance adjustment].
Q: What does the HC5 suffix typically indicate in this bearing series?
A: In the manufacturer’s designation system, HC5 generally refers to a hybrid bearing variant where rolling elements are made from silicon nitride ceramic rather than bearing steel. This reduces centrifugal loading at high speeds and provides electrical insulation — both valuable in spindle and traction motor applications. Confirm the exact specification against the current manufacturer catalog for your production batch.
Secure Your Spindle Bearing with Verified Traceability
Send your OEM equipment number or full operating parameters today — we will confirm designation match, batch availability, and documentation readiness within one business day.
