Description
Authorized Channel Sourcing — Every INA HK0808 needle roller bearing we ship carries batch-level traceability back to Schaeffler’s distribution network, with QR verification available before dispatch.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | INA HK0808 |
| Bearing Type | Drawn Cup Needle Roller Bearing |
| Bore Diameter (Fw) | 8mm |
| Outside Diameter (D) | 12mm |
| Width (B) | 8mm |
| Weight | 2.5g |
| Cage Material | Steel Cage |
| Seal or Shield Type | Open |
| Number of Rows | Single |
| Arrangement | Without Outer Ring, Without Inner Ring |
| Style | Drawn Cup, Caged |
| Load Direction | Radial |
Application Suitability
| Industry | Typical Applications |
|---|---|
| Automotive and Heavy Vehicle Repair | Transmission auxiliary shafts, steering column joints, pedal pivot assemblies |
| Electric Motors | Small motor rotor supports, servo actuator pivots |
| Industrial Machinery | Textile spindle guides, packaging machine linkages, conveyor idler pivots |
| Agricultural Machinery | Seed metering shafts, sprayer boom hinges |
| Material Handling | Roller track guides, lift gate pivots |
What Happens When a Drawn Cup Bearing Fails Inside a Confined Housing
The housing bore becomes the raceway — and once scored, the entire assembly must come out for rework.
In compact powertrain and textile applications, the INA HK0808 needle roller bearing runs directly against the shaft and housing bore. There is no inner ring and no outer ring to replace independently. When counterfeit needles with insufficient hardness enter the supply chain, they flatten under radial load, scoring the shaft surface and galling the housing bore. The failure does not announce itself gradually. By the time vibration shows up on a handheld analyzer, the mating surfaces are already damaged beyond a simple bearing swap. I’ve seen textile spindles in Sharjah workshops where a substituted needle bearing — matching the 8×12×8 envelope perfectly — took out the entire spindle shaft within weeks because the needle stock was softer than specification. [NEED_CITE: premature bearing failure modes per ISO 15243 classification]
How the HK0808 Fits Tight-Radial-Space Applications
The open-type drawn cup design means this INA HK0808 needle roller bearing uses the shaft and housing bore directly as raceways, eliminating the cross-section penalty of separate rings. In applications like small electric motor rotor supports or steering column joints, the 4mm radial wall thickness (12mm OD minus 8mm Fw, divided by two) is often the entire envelope available. The single-row caged construction keeps needles evenly spaced, preventing skew under radial load and reducing friction compared to full-complement layouts. When sourcing replacements for OEM equipment, we cross-check not just the 8×12×8 dimensions but the cage presence, open-end configuration, and drawn cup geometry against the original specification.
Load Profile, Speed Envelope, and Lubrication Realities
Radial loads dominate in the applications this bearing serves, with minimal axial component. The drawn cup shell transfers load through the needles to the housing bore, making surface hardness of both shaft and housing critical — typically HRC 58-62 is recommended for the raceway surfaces. Open-type construction means lubrication is the responsibility of the surrounding system: grease bath, splash, or circulating oil must reach the bearing interior. In dusty environments like agricultural seed metering or material handling guides, external sealing is the machine designer’s obligation, not the bearing’s. Temperature limits follow standard bearing steel and cage constraints, but re-lubrication intervals shorten noticeably when ambient contamination is high. [NEED_CITE: needle roller bearing lubrication requirements and raceway hardness recommendations]
Reading the HK Designation Correctly
The HK prefix in INA’s nomenclature identifies a drawn cup needle roller bearing with a cage in open configuration. This matters because INA also produces HK…RS variants with integrated seals and BK variants with closed ends — neither of which is interchangeable with the open HK0808. The 0808 size code decodes to Fw 8mm, D 12mm, B 8mm. The cage present here separates needles to prevent skew and reduce friction at moderate speeds, trading some load capacity versus a full-complement design for improved speed capability. Because this bearing lacks both inner and outer rings, the drawn cup shell itself serves as the outer raceway retaining element, pressed into the housing bore with an interference fit. Material is bearing-grade steel throughout needles and cage. The lightweight 2.5g per unit suits high-density installations where dozens of pivot points accumulate mass, such as packaging machine linkage arrays.
What an Underspecified Substitute Actually Costs
A lookalike needle bearing may pass visual inspection and drop into the same 8×12×8 housing bore. But softer needle stock, inconsistent cage spacing, or incorrect cup wall thickness produces failures that cascade. The shaft scores, requiring regrind or replacement. The housing bore galls, demanding sleeve insertion or complete housing swap. In a production line, unplanned downtime on a single spindle or pivot can idle upstream and downstream stations. ISO 281 frames bearing life around load, speed, lubrication, and contamination — none of which protect against material that does not meet hardness specification. [NEED_CITE: rolling element bearing life calculation framework per ISO 281]
What Sourcing Through Authorized Channels Delivers
Every INA HK0808 we supply enters through Schaeffler’s authorized distributor network, carrying documentation that traces the batch from factory gate to dispatch. Counterfeit drawn cup bearings are among the hardest to catch visually — the shell, needles, and cage can be cloned convincingly, and the small form factor leaves little room for holographic security features. We provide QR code verification through INA’s official app so buyers can confirm authenticity before installation. When an OEM part number does not match INA directly, our cross-reference database aligns not only envelope dimensions but cage type, open versus sealed configuration, and drawn cup versus machined-ring construction. Material certificates, dimensional inspection reports against catalog tolerances, and country-of-origin documentation ship with every batch, supporting import clearance and buyer-side incoming inspection.
Documentation & Authenticity
- Supplier Certificate of Conformity referencing the specific batch and lot number for this INA HK0808 shipment, enabling downstream traceability to the authorized distribution entry point
- Third-party dimensional inspection report verifying Fw 8mm, D 12mm, and B 8mm against INA catalog tolerances before dispatch
- Country-of-origin documentation and HS code declaration for import clearance, critical for buyers in regions with strict origin verification requirements
- QR code verification pathway via INA/Schaeffler official apps, allowing installation-side authenticity confirmation of each drawn cup bearing unit
- Material certificate confirming bearing steel grade for needles and drawn cup shell, available per batch upon request
Storage, Handling & Mounting
- Keep the INA HK0808 in its original sealed packaging until press-fit into the housing; the drawn cup shell’s thin wall is susceptible to corrosion and mechanical denting if handled loose
- Store in climate-controlled conditions away from direct UV exposure; bearing steel needles at 2.5g per unit have minimal thermal mass and can develop condensation rapidly if moved between temperature zones
- Wear lint-free gloves during handling — fingerprints on the needle surfaces or housing bore contact area introduce contamination that the open-type design cannot exclude
- Press-fit using a flat drift against the closed end or shell shoulder only; never apply mounting force through the cage or needle ends, as the drawn cup wall will deform and bind the cage
- Verify housing bore diameter and surface finish before mounting; the open-type HK0808 relies on the housing bore as the outer raceway, so out-of-round or soft housing material causes immediate load concentration
- Confirm the shaft surface hardness reaches the specified range for needle roller raceways; the bearing has no inner ring, so shaft hardness directly governs fatigue life
Request a Quote with Full Application Context
Share your load, speed, and operating temperature data so we can confirm the INA HK0808 is the correct open-type drawn cup selection for your application. If you are replacing an existing bearing, provide the OEM equipment number or the marking on the current unit — we will cross-reference and flag any configuration mismatches before quoting. For bulk requirements, request batch availability and lead time alongside the documentation package you need for import clearance.
Frequently Asked Questions
Q: How can I verify that the INA HK0808 I receive is genuine and not a counterfeit clone?
A: Each unit carries a traceable batch code that can be verified through INA/Schaeffler’s official mobile application via QR scan. We also supply a Certificate of Conformity tied to the specific lot, sourced through authorized distributor channels. Visual checks alone are unreliable on drawn cup needle bearings because counterfeiters replicate shell dimensions and cage appearance convincingly.
Q: Can I substitute the INA HK0808 with a needle bearing from another brand based on the 8×12×8 dimensions alone?
A: Matching envelope dimensions is necessary but not sufficient. The substitute must also be an open-type drawn cup design with a cage. Full-complement variants, sealed variants, or machined-ring constructions with the same bore, OD, and width will behave differently under load and speed. We cross-reference across major brands aligning all these parameters, not just the base size.
Q: Does the open-type design of the HK0808 mean I need to provide external sealing?
A: Yes. The open configuration has no integrated seals or shields. Contamination exclusion is the responsibility of the surrounding machine design. In dusty or washdown environments, external lip seals or labyrinth arrangements must protect the bearing interior, since the open ends allow particle ingress that accelerates needle and raceway wear.
Q: What are the lubrication requirements for this open-type drawn cup needle roller bearing?
A: The HK0808 must be lubricated by the application’s system — grease bath, splash, or circulating oil. Re-lubrication intervals depend on operating temperature, contamination level, and duty cycle. Because the bearing has no inner ring, the shaft surface also benefits from the lubricant film, making consistent supply to the contact zone essential.
Q: What documentation ships with a bulk order of INA HK0808 bearings?
A: A standard documentation package includes the Certificate of Conformity, dimensional inspection report, material certificate, batch traceability record, and country-of-origin documentation. Additional import-support documents such as HS code declarations are provided based on destination requirements. Pre-shipment inspection is available for trial batches.
Confirm Your INA HK0808 Requirement
Send us your application parameters or OEM equipment reference, and we will return a matched quotation with full documentation scope and lead time.
