Description
Authorized Channel Procurement — Each SKF 7002 CDGA/P4A is sourced through traceable distributor networks with batch-level documentation and QR verification pathways.
Technical Specifications
| Parameter | Value |
|---|---|
| Designation | SKF 7002 CDGA/P4A |
| Bearing Type | Angular Contact Ball Bearing |
| Bore Diameter (d) | 15 mm |
| Number of Rows | Single Row |
| Precision Class | P4A |
| Contact Angle | 15° |
| Preload | Light preload |
| Arrangement | Universal Matching |
| Origin | China |
| Weight | 0.100 kg |
The GA suffix denotes universal matching with light preload grouping; specific preload force values should be confirmed against the manufacturer catalog for paired mounting calculations.
Application Suitability
| Industry | Typical Applications |
|---|---|
| Machine Tool | High-speed milling spindles, CNC grinding quills, precision lathe headstocks |
| Robotics | Harmonic drive inputs, joint rotary actuators, gimbal positioning stages |
| Precision Equipment | Optical inspection stages, coordinate measuring machine probes, semiconductor wafer handling arms |
When a Base Number Match Leads to Spindle Scrap
Matching 7002 by designation alone while ignoring the CD, GA, and P4A suffixes invites thermal binding and surface finish rejection on precision spindles.
I once reviewed a case where a buyer substituted a standard P0 angular contact for a P4A requirement on a CNC grinding quill. The bench test looked acceptable, but under continuous high-speed cutting, vibration amplitude climbed and workpiece Ra values drifted out of tolerance within hours. The raceway showed early fatigue patterns consistent with excessive internal clearance and insufficient preload control. This SKF 7002 CDGA/P4A angular contact ball bearing exists precisely because spindle applications demand that every suffix — contact angle, preload class, and tolerance grade — align with the thermal and dynamic reality of the cutting zone [NEED_CITE: rolling bearing failure mode classification per ISO 15243].
How the 15° Contact Angle Serves Radial-Dominant Spindle Loads
The CD suffix indicates a 15° contact angle with optimized internal geometry, which generates measurably lower friction heat than 25° or 40° variants when radial forces dominate the load spectrum. On high-speed milling spindles where axial thrust remains moderate, this thermal advantage directly supports thermal stability and extends grease service intervals. The SKF 7002 CDGA/P4A angular contact ball bearing pairs this low-heat profile with P4A running accuracy, keeping radial runout tight enough for fine surface finishes.
Thermal Growth, Preload Drift, and Speed Limits
Spindle bearings operate in a narrow thermal window. As the shaft heats during extended cutting cycles, differential expansion between inner ring, balls, and outer ring shifts the preload state. The GA suffix provides light universal preload, allowing flexible DB, DF, or DT pairing without specifying exact preload values at order placement — but the light grouping means thermal growth must be carefully modeled to avoid either preload loss or excessive internal stress [NEED_CITE: angular contact bearing preload and thermal interaction principles]. The P4A precision class adds tighter running accuracy beyond standard P4 dimensional tolerances, which matters when the spindle nose must hold sub-micron TIR at 15,000 RPM and above.
Decoding the Suffix Stack: CD, GA, and P4A
The 15° contact angle from the CD designation prioritizes radial rigidity and low friction heat, making it the preferred choice for motorized spindles where axial loads are secondary. The GA universal matching suffix means any combination of bearings from this batch can be paired in back-to-back, face-to-face, or tandem arrangements without custom selection — the factory has already grouped them within a narrow preload band. P4A goes one step beyond ISO Class 4 dimensional tolerances by adding stricter running accuracy requirements, specifically controlling radial and axial runout of the inner ring relative to the bore. Together, these three suffix elements define a bearing that holds position under thermal load while minimizing the heat it generates.
The Hidden Cost of Precision Mismatch on a Grinding Quill
Installing a P5 or P0 grade where P4A is specified does not merely reduce accuracy margin — it accelerates fatigue through uneven load distribution across the ball complement. Under ISO 281 life calculation frameworks, running accuracy deviations increase dynamic stress concentrations that shorten L10 life far more than the nominal load rating would suggest. A counterfeit or mis-specified replacement may pass visual inspection and basic dimensional checks, yet deliver soft inner rings, inconsistent cage pocket spacing, or cloned QR codes that fail under sustained high-speed operation. The result is unplanned downtime, scrapped workpieces, and warranty exposure that dwarfs the original procurement savings [NEED_CITE: bearing life adjustment factors per ISO 281 for precision and lubrication conditions].
Sourcing Confidence for Precision Spindle Bearings
Every SKF 7002 CDGA/P4A we supply comes through authorized distributor channels with full batch traceability, not from open-market brokers who cannot guarantee storage conditions or provenance. We run QR code verification through the official SKF application before shipment, confirming the code resolves to a valid production lot. Our cross-reference database aligns not just the base 7002 designation but also the 15° contact angle, light preload grouping, and P4A tolerance class — so if you need an NSK or FAG equivalent, we match all three suffix layers, not just the number. For new applications, we review your speed, load, and mounting envelope before confirming the selection, and we provide country-of-origin documentation to support import clearance in markets with strict authentication requirements.
Documentation & Authenticity
- Certificate of Conformity from the authorized distributor confirming batch traceability for this specific SKF 7002 CDGA/P4A lot
- QR code verification pathway through the official SKF app, confirming production date and origin before shipment
- Country-of-origin documentation package supporting import clearance and buyer authentication requirements
- Third-party running accuracy inspection report confirming P4A radial and axial runout values prior to dispatch
- Material traceability linking the bearing batch to the manufacturer’s steel certification records
Storage, Handling & Mounting
- Keep the SKF 7002 CDGA/P4A sealed in original packaging until mounting; early opening risks contamination of the precision raceways and loss of factory preload pairing marks for universal matching sets
- Store in a climate-controlled environment below 25°C with relative humidity under 60% to prevent corrosion on the P4A-precision surfaces
- Handle with clean lint-free gloves; fingerprints on the bore or outer diameter can introduce localized corrosion that degrades running accuracy at spindle speeds
- For back-to-back or face-to-face pairing, mount bearings in the sequence indicated by the factory matching marks; the GA light preload grouping assumes correct orientation to achieve the designed internal clearance
- Use induction heating for inner ring installation on the 15 mm bore, targeting 80–100°C to avoid exceeding the tempering threshold of the P4A-grade rings
- After mounting, verify axial preload by measuring starting torque or using a dial indicator on the spindle nose; the universal GA matching allows flexible pairing but still requires confirmation that thermal expansion has not eliminated the light preload
Getting the Right Precision Grade for Your Spindle
Share your spindle speed, load direction, and thermal profile so we can confirm whether the 15° contact angle and GA light preload grouping match your operating conditions. Provide the OEM equipment number if you are replacing an existing bearing and need cross-reference verification across clearance, cage, and precision suffixes. We will return a technical selection review, authenticity documentation pathway, and confirmed lead time before you commit to a trial batch.
Frequently Asked Questions
Q: What does the GA suffix mean on this SKF 7002 CDGA/P4A?
A: GA indicates universal matching with light preload grouping. It means any bearing from this batch can be paired in DB, DF, or DT arrangement without custom selection, and the factory has already matched them within a narrow light preload band.
Q: How does the 15° contact angle differ from 25° on angular contact bearings?
A: The 15° angle from the CD suffix generates lower friction heat under radial-dominant loads, making it suitable for high-speed spindles where axial thrust is moderate. A 25° angle would provide higher axial rigidity but at the cost of increased heat generation.
Q: Can I substitute a P5 precision grade for P4A on a machine tool spindle?
A: P4A adds stricter running accuracy requirements beyond standard P5 dimensional tolerances. On precision grinding or milling spindles requiring tight runout control, downgrading to P5 may introduce vibration and surface finish issues under sustained high-speed operation.
Q: How do I verify the authenticity of this SKF 7002 CDGA/P4A?
A: Each bearing carries a QR code verifiable through the official SKF application, confirming production lot and origin. We provide this verification pathway along with the Certificate of Conformity and country-of-origin documentation before shipment.
Confirm Your Spindle Bearing Specification
Send your application parameters or OEM equipment number for a technical selection review and cross-reference check across contact angle, preload, and precision class.
SKF 7002 CDGA/P4A angular contact ball bearing
