Description
Authorized Channel Sourcing — Every SKF NN 3022 TN9/SP shipped from our warehouse arrives with traceable batch documentation tied directly to the manufacturer’s distribution network, ensuring spindle shops can verify provenance before the bearing ever touches a machine tool.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | SKF NN 3022 TN9/SP |
| Bearing Type | Double Row Cylindrical Roller Bearing |
| Bore Diameter (d) | 110 mm |
| Outside Diameter (D) | 170 mm |
| Width (B) | 45 mm |
| Dynamic Load Rating (C) | 220 kN |
| Static Load Rating (C₀) | 360 kN |
| Fatigue Load Limit (Pu) | 41.5 kN |
| Limiting Speed (Grease) | 5,000 r/min |
| Limiting Speed (Oil-air) | 5,600 r/min |
| Weight | 3.4 kg |
| Cage Material | TN9 — Glass Fiber Reinforced Polyamide 6,6 |
| Seal or Shield Type | Open |
| Precision Class | SP |
| Bore Type | Cylindrical |
| Number of Rows | Double Row |
| Origin | China |
Note: The SP precision class designation sits outside the standard ISO P-series table commonly referenced for cylindrical roller bearings; final tolerance band confirmation should be checked against the current SKF super-precision catalog for this specific production lot.
Application Suitability
| Industry | Typical Applications |
|---|---|
| Machine Tool Manufacturing | CNC lathe spindle rear support, machining center spindle radial positioning |
| Steel & Metallurgy | Rolling mill work roll neck support, continuous caster guide rollers |
| Heavy-Duty Gearboxes | High-speed pinion shaft radial support, industrial reducer output stages |
| Precision Industrial Equipment | High-precision grinding head spindles, rotary table positioning bearings |
What a Precision Mismatch Costs on a CNC Spindle
A standard P0 cylindrical roller bearing installed where SP precision is required will generate measurable runout that degrades surface finish within weeks.
I reviewed a teardown report where a Southeast Asian spindle shop cross-referenced an NN 3022 for their CNC lathe. The previous supplier matched the base number but ignored the /SP suffix entirely — shipped a P0 grade bearing with a steel cage instead of the TN9 polyamide cage the spindle was designed around. The bearing ran hot inside three weeks. High-speed vibration cracked the cage, and the resulting spindle rebuild cost the shop roughly ten times what the correct bearing would have. Suffix errors on super-precision bearings are not cosmetic — they show up on the workpiece as chatter marks, dimensional drift, and scrapped batches. [NEED_CITE: spindle bearing failure modes linked to precision class mismatch]
How This Bearing Matches High-Speed Spindle Demands
The SKF NN 3022 TN9/SP double row cylindrical roller bearing targets the rear support position in high-speed machine tool spindles, where radial rigidity and thermal stability matter more than axial location. The double-row roller complement delivers the radial load capacity needed to resist cutting forces, while the open design allows the bearing to integrate directly with the spindle’s oil-air or oil-mist lubrication circuit. When we supply this bearing to spindle rebuilders, we cross-check the suffix string against the OEM equipment drawing — not just the base number — so the cage material and precision class land correctly the first time.
Thermal Growth, Lubrication, and Mounting Realities
Spindle bearings in CNC machining centers routinely see temperature differentials between the inner ring and housing that drive thermal expansion. An open bearing like the NN 3022 TN9/SP relies on external forced lubrication — typically oil-air at controlled flow rates — to carry heat away from the raceway contact zone. Grease lubrication in this position risks starvation at sustained speeds near the 5,000 r/min grease limit, particularly if the housing lacks adequate cooling fins. Mounting demands care: the cylindrical bore requires a controlled interference fit on the shaft, and the separable inner and outer ring halves must be installed without cocking to avoid edge-loading the rollers. [NEED_CITE: cylindrical roller bearing mounting practices for machine tool spindles]
Decoding the TN9 Cage and SP Precision Class
The TN9 suffix identifies an injection-molded, glass fiber reinforced polyamide 6,6 cage. Compared to a machined brass cage, the TN9 cage runs lighter, generates less friction at high speed, and maintains dimensional stability through the operating temperature range typical of spindle applications. The trade-off is an upper temperature ceiling lower than brass — polyamide cages generally should not be exposed to sustained temperatures above the manufacturer’s stated limit, and they are incompatible with certain aggressive synthetic lubricants. The SP precision class sits above standard P0 and P6 tolerances, delivering tighter bore and OD tolerances along with reduced radial runout, which is essential for preventing vibration-induced surface finish defects on machined parts. The NN 30 series inner ring carries three integral flanges while the outer ring is flangeless, permitting limited axial float to accommodate thermal shaft growth without binding.
The Hidden Expense of a Wrong Suffix Decision
Installing a bearing with incorrect precision, cage material, or clearance specification in a spindle or gearbox produces a cascade of costs that dwarf the component price. Premature cage failure sends debris into the raceway, scoring the shaft journal and destroying the housing seat — turning a routine bearing swap into a full spindle rebuild. Under ISO 15243 failure classification, fatigue spalling accelerated by cage fragmentation is a well-documented failure path that voids equipment warranties when traced back to non-conforming replacement parts. Shops that accept the lowest quote without verifying the complete suffix string regularly absorb unplanned downtime, expedited freight on emergency replacements, and scrapped production lots. [NEED_CITE: ISO 15243 bearing damage classification categories]
Why Spindle Shops and MRO Buyers Source Through Us
Every SKF NN 3022 TN9/SP double row cylindrical roller bearing we quote moves through authorized distributor channels with full batch and lot traceability from origin to your receiving dock. We verify each suffix — TN9 cage, SP precision — against the application parameters you share before any order ships. Our cross-reference database aligns clearance, cage material, and precision class across SKF, NSK, FAG, NTN, TIMKEN, and KOYO, so substitution decisions are made on complete technical equivalence rather than base number alone. Country-of-origin documentation and HS code support arrive with the shipment for straightforward customs clearance. We also provide QR code verification pathways through the brand’s official apps so your quality team can confirm authenticity in-house before mounting.
Documentation & Authenticity
- Supplier Certificate of Conformity (COC) referencing the specific production batch and lot number for this NN 3022 TN9/SP
- QR code verification pathway via SKF official mobile apps to confirm the bearing left the manufacturer’s authorized distribution network
- Third-party pre-shipment dimensional inspection report verifying bore, OD, width, and runout against SP class tolerances
- Material certificate confirming bearing steel specification and heat treatment compliance
- Country-of-origin documentation and HS code declaration prepared for import customs clearance at destination
Storage, Handling & Mounting
- Keep this open-type NN 3022 TN9/SP sealed in its original packaging until the moment of mounting; the polyamide TN9 cage is susceptible to surface contamination that accelerates wear once the rust-preventive oil film is disturbed.
- Store flat in a vibration-free, climate-controlled area with relative humidity below 60% to prevent condensation from migrating past the packaging and reaching the exposed raceway surfaces.
- Use clean, lint-free gloves during handling; fingerprint moisture on the SP-precision ground surfaces can initiate corrosion pits that propagate into early spalling under spindle operating loads.
- Heat the inner ring using an induction heater with automatic demagnetization to the manufacturer’s recommended temperature range for the 110 mm bore; never apply an open flame, as localized overheating will degrade the dimensional accuracy achieved at SP precision level.
- Confirm the shaft seat diameter and roundness against the bearing’s interference fit tolerance band before pressing the separable inner ring onto the journal; any out-of-round condition transfers directly into the roller contact zone and shows up as vibration at operating speed.
Start Your Technical Review
Share your spindle model number, operating speed range, and lubrication method so we can confirm the SKF NN 3022 TN9/SP double row cylindrical roller bearing matches your application — or identify a better-suited alternative from the cross-reference matrix. If you are replacing an existing bearing, send us the full designation string printed on the outer ring along with your OEM equipment number for complete suffix verification. Request the documentation package and batch availability confirmation before placing your order.
Frequently Asked Questions
Q: How can I verify that the SKF NN 3022 TN9/SP I received is genuine?
A: Genuine SKF super-precision bearings carry a unique QR code on the packaging that links to the manufacturer’s official verification app. Scanning the code confirms the batch, production facility, and authorized distribution path. We also supply the Certificate of Conformity and recommend a pre-mounting dimensional check using calibrated instruments to compare bore, OD, and runout values against the SP tolerance band.
Q: Why does the TN9 polyamide cage matter for my spindle application?
A: The TN9 cage is lighter than a machined brass alternative, which reduces centrifugal loading on the rollers at high speed. This lowers friction and operating temperature inside the spindle. The trade-off is a lower maximum continuous temperature threshold and incompatibility with certain synthetic lubricants, so always confirm your spindle oil specification is compatible with polyamide cage materials.
Q: What is the difference between SP precision and standard P5 or P4 for cylindrical roller bearings?
A: SP is a super-precision class defined by SKF for machine tool spindle applications. It imposes tighter bore and outside diameter tolerances, along with reduced radial runout, compared to standard ISO P5 or P4 classes. The tighter tolerances translate directly into lower vibration and better surface finish on machined components.
Q: Can I substitute a different brand for the NN 3022 TN9/SP?
A: Cross-brand substitution is possible, but the replacement bearing must match on all three axes: clearance class, cage material, and precision level — not just the base number. We provide a complete cross-reference comparison across SKF, NSK, FAG, TIMKEN, NTN, and KOYO that aligns these parameters so the substituted bearing performs identically in your spindle.
Q: What does the SP suffix mean on this bearing?
A: SP designates a super-precision tolerance class specific to SKF’s machine tool bearing range. It is not part of the standard ISO P-series scale. The exact tolerance values should be confirmed against the current SKF super-precision catalog for the production batch in question.
Confirm Your SKF NN 3022 TN9/SP Specification and Availability
Send your application parameters or OEM equipment number for a complete technical review and suffix verification.
Reach our technical sales team through the contact channels listed on our company profile.
