Description
Authorized-Channel Traceability — Every INA NKI5/12-TV-XL needle roller bearing we supply ships with a complete distributor-chain documentation package, from certificate of conformity to batch-level lot traceability.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | INA NKI5/12-TV-XL |
| Bearing Type | Needle Roller Bearing with Inner Ring |
| Bore Diameter (d) | 5 mm |
| Outside Diameter (D) | 15 mm |
| Width (B) | 12 mm |
| Weight | 0.012 kg |
| Cage Material | Polyamide (PA) |
| Number of Rows | Single |
| Load Direction | Radial |
| Style | With Inner Ring, Open Type |
| Material | Bearing Steel |
| Origin | Germany (subject to batch) |
The XL suffix on this designation remains unverified against the current INA catalog and should be confirmed with the manufacturer’s documentation before final procurement.
Application Suitability
| Industry | Typical Applications |
|---|---|
| Industrial Machinery | Compact pivot joints, small gear selector shafts |
| Electric Motors | Rotor support in fractional-horsepower motors |
| Automotive Repair | Steering column intermediate shafts, pedal pivot assemblies |
| Agricultural Machinery | Throttle linkage pivots, sprayer boom hinges |
| Material Handling | Conveyor guide roller end-pivots |
Why the Polyamide Cage on a 5 mm Needle Roller Changes Everything
Most MRO buyers match the NKI base number and stop there — the TV cage suffix is where field failures originate.
Compact needle roller bearings operate in space-constrained assemblies where vibration, marginal lubrication, and thermal cycling are constant. A procurement engineer sourcing a replacement for a textile spindle or small gearbox may find an "equivalent" NKI5/12 with a stamped steel cage at a lower unit price. That substitution ignores the fact that polyamide cages run quieter, weigh less, and tolerate brief lubrication starvation far better than their steel counterparts in high-speed light-load applications. When the cage material mismatches the operating envelope, the result is not immediate seizure but gradual cage wear, needle skew, and eventual shaft scoring — a failure pattern that ISO 15243 classifies under cage-related fatigue [NEED_CITE: rolling bearing failure mode classification per ISO 15243]. We have seen batches arrive at workshops with cloned markings and soft inner rings that pass a quick caliper check but fail within weeks because the raceway hardness never reached specification.
Matching the INA NKI5/12-TV-XL to Light-Load High-Speed Assemblies
The 5 mm bore and 15 mm outside diameter place this bearing squarely in the micro-pivot category where radial space is minimal but rotational speed can be substantial. Polyamide cages reduce the overall rotating mass, which matters when a small electric motor or gearbox shaft spins at several thousand RPM. The integrated inner ring means the mating shaft does not need through-hardening or precision grinding — a significant cost saving in repair scenarios where replacing the entire shaft would require disassembly of surrounding components. When a customer sends us an OEM equipment number, we cross-check not only the base dimensions but also cage type, confirming that a TV-suffix polyamide cage was specified in the original design rather than defaulting to whatever is cheapest on the shelf.
Compact Envelope, Unforgiving Operating Conditions
Radial loads on a 5 mm bore needle roller are inherently modest, yet the load per needle is high because the rolling elements are so small. Any misalignment, contamination, or lubrication gap is amplified at this scale. In an open-type design like the NKI5/12-TV, external sealing is the responsibility of the housing — the bearing itself has no integrated shields or contact seals. That makes the cleanliness of the assembly environment critical during installation [NEED_CITE: needle roller bearing contamination sensitivity in compact assemblies]. Temperature is another factor: polyamide cages have a continuous operating ceiling well below brass or steel cages, so if the application involves sustained heat above normal ambient ranges, cage degradation becomes a real risk. Engineers need to evaluate whether the surrounding housing provides adequate heat dissipation before specifying a polyamide-caged bearing in a warm-zone application.
Decoding the Critical Suffixes and Specs
The TV suffix designates an injection-molded polyamide cage — lighter than stamped steel, quieter in operation, and better at retaining lubricant within the rolling zone during brief starvation periods. This cage type is standard for many INA needle rollers in the smaller size range where speed and noise matter more than extreme load capacity. The NKI series designation tells us the bearing ships with a precision-ground inner ring, which is essential when the shaft surface cannot serve as a raceway — either because the shaft is not hardened or because it requires frequent removal for maintenance. The open-type construction allows grease or oil-mist lubrication to be applied externally, giving the maintenance team flexibility to match the lubricant to the operating environment rather than being locked into a factory-fill grease that may not suit the actual duty cycle. At 12 mm width, the bearing offers a generous contact length for its diameter, distributing radial load across more needles and reducing Hertzian contact stress on each element [NEED_CITE: Hertzian contact stress distribution in needle roller bearings].
The Hidden Cost of Ignoring Suffix and Origin Verification
Correct specification paired with a verifiable supply chain keeps an assembly running through its expected L10 life. Wrong cage material, an unconfirmed XL variant, or a counterfeit inner ring that is softer than specification shifts the failure mode from predictable fatigue to sudden, unplanned downtime — the kind that halts a production line while a technician diagnoses a problem that should never have occurred. ISO 281 life calculations assume correct material hardness, proper lubrication, and contamination-free operation; when any of these assumptions is violated by a substandard component, the calculated life becomes meaningless [NEED_CITE: ISO 281 bearing life calculation assumptions]. The downstream cost is never just the bearing itself — it is the labor to disassemble, the secondary damage to shafts and housings, and the production hours lost while a replacement is sourced.
How We Reduce Procurement Risk on Compact Needle Rollers
Our sourcing model operates through authorized distributor channels rather than open-market trading, which means every INA NKI5/12-TV-XL we quote comes with a traceable batch path back to the manufacturer’s production facilities. When a customer requires cross-brand interchange — perhaps an IKO or NTN equivalent is more readily available in their region — we match on bore, outside diameter, width, cage material, and inner ring presence simultaneously, not just the base number. We provide country-of-origin documentation that satisfies customs requirements in markets with strict import controls. For buyers concerned about counterfeit exposure, we guide them through the manufacturer’s official app verification pathway so they can scan and confirm authenticity on arrival. Dimensional inspection reports and certificates of conformity accompany every shipment, giving procurement teams the paper trail their quality systems demand.
Documentation & Authenticity
- Certificate of Conformity issued through the authorized INA distribution channel, referencing batch and lot number
- Material certificate confirming bearing steel composition for inner ring and outer ring
- Dimensional inspection report verifying Fw 5 mm, D 15 mm, and B 12 mm within tolerance
- Country-of-origin certificate supporting import clearance in regulated markets
- QR code verification pathway via the manufacturer’s official app for on-site authenticity confirmation
Storage, Handling & Mounting
- Retain the original sealed packaging for this open-type bearing until the moment of installation to prevent contaminant ingress into the exposed needle-and-cage assembly
- Store below 40 °C and away from direct UV exposure, since prolonged heat or sunlight degrades the polyamide cage material before the bearing ever reaches the shaft
- Use lint-free gloves when handling the 5 mm bore needles; skin oils on this small a raceway surface can initiate corrosion pitting within days
- Apply the specified grease or oil-mist lubricant immediately after mounting, as the open design provides no factory-fill protection against dry running
- Verify shaft and housing tolerances match the inner ring and outer diameter fits before pressing — the compact 15 mm OD leaves minimal margin for interference errors
Before You Request a Quote
Share your application parameters — load profile, speed range, operating temperature, and housing sealing arrangement — so we can verify that the INA NKI5/12-TV-XL polyamide cage and open-type design suit your specific conditions. If you are replacing an existing bearing, send us the OEM equipment number or a photo of the current bearing markings so we can run a full cross-reference check covering dimensions, cage material, and inner ring type. We can also provide the documentation package your import process requires before you commit to an order.
Frequently Asked Questions
Q: How can I verify the authenticity of an INA needle roller bearing after delivery?
A: INA provides an official app that scans the QR code on the product packaging and bearing marking. This links to batch and lot traceability data held by the manufacturer. We guide every buyer through this verification pathway and supply supporting documentation including a certificate of conformity.
Q: What is the difference between NKI and NK series needle roller bearings?
A: NKI bearings include a precision-ground inner ring, while NK bearings are designed for applications where the shaft itself is hardened and ground to serve as the inner raceway. The NKI5/12-TV-XL ships with its own inner ring, which simplifies assembly when the shaft cannot be through-hardened.
Q: When should I choose a polyamide cage over a steel cage for a needle roller bearing?
A: Polyamide cages are preferred in applications involving higher speeds, lower noise requirements, and light-to-moderate loads where brief lubrication starvation may occur. Steel cages are specified for sustained high temperatures or heavy shock loads. The TV suffix on this bearing confirms the polyamide cage.
Q: Can I use a different brand as a substitute for the INA NKI5/12-TV-XL?
A: Cross-brand substitution is possible when bore, outside diameter, width, cage material, and inner ring type all match. We provide a complete interchange comparison so that substitutions are made on full specification alignment, not just the base number.
Q: What lubrication is recommended for an open-type needle roller bearing like this?
A: Open-type bearings rely on external lubrication applied by the maintenance team. The choice between grease and oil-mist depends on operating speed, temperature, and contamination risk. We can provide application-based lubrication guidance when you share your operating parameters.
Start with the Application Details
Send us your load, speed, temperature, and OEM equipment number so we can confirm the INA NKI5/12-TV-XL is the right fit and prepare your documentation package.
