NSK 6306-NR Bearing — Specifications, Dimensions & Cross-Reference

The NSK 6306-NR is a deep groove ball bearing with snap ring groove manufactured by NSK. It belongs to the 6300 series and features dimensions of 30 × 72 × 19 mm (bore × OD × width). This bearing has a dynamic load rating of 28,100 N and a static load rating of 16,000 N, making it suitable for heavy-duty applications.

Technical Specifications

Dimensions
Bore Diameter (d)	30 mm
Outside Diameter (D)	72 mm
Width (B)	19 mm
Weight	0.327 kg

Performance
Dynamic Load Rating (Cr)	28,100 N
Static Load Rating (C₀r)	16,000 N
Limiting Speed (Grease)	9,000 rpm
Limiting Speed (Oil)	11,000 rpm

💡 Application Note: The 6300 series bearings are commonly used in heavy-duty electric motors, mining equipment, construction machinery, and industrial gearboxes. The -NR suffix indicates an external snap ring groove on the outer ring, allowing easy axial location in housing bores.

Brand Cross-Reference — 6306-NR Equivalents

The following bearings from other manufacturers are interchangeable with the NSK 6306-NR. All share identical dimensions (30×72×19mm) and comparable load ratings:

Brand	Part Number	Dynamic Load (N)	Static Load (N)
NSK	NSK 6306-NR ✦	28,100	16,000
Timken	Timken 6306-NR	28,100	16,000
SKF	SKF 6306-NR	28,100	16,000
NTN	NTN 6306-NR	28,100	16,000
NACHI	NACHI 6306-NR	28,100	16,000
KOYO	KOYO 6306-NR	28,100	16,000
FAG	FAG 6306-NR	28,100	16,000
Timken	Timken 6306-NR	28,100	16,000
NTN	NTN 6306-NR	28,100	16,000
SKF	SKF 6306-NR	28,100	16,000

Available Variants

The NSK 6306 base bearing is available in these configurations:

NSK 6306-ZZ-C3

Double shielded, C3 clearance

NSK 6306-2RS-C3

Double sealed, C3 clearance

NSK 6306-C3

Open, C3 clearance

NSK 6306-2Z

Double metal shielded (ISO)

NSK 6306-ZZ

Double metal shielded

NSK 6306-2RS

Double rubber sealed

NSK 6306

Open (no seal/shield)

Frequently Asked Questions

What are the dimensions of the NSK 6306-NR?

The NSK 6306-NR has a bore diameter of 30mm, outside diameter of 72mm, and width of 19mm. It weighs 0.327kg.

What is the load capacity of the NSK 6306-NR?

The dynamic load rating (Cr) is 28,100 N and the static load rating (C₀r) is 16,000 N. The maximum recommended speed is 9,000 rpm with grease lubrication or 11,000 rpm with oil lubrication.

What bearings are equivalent to NSK 6306-NR?

The 6306-NR is manufactured by multiple brands including SKF, NTN, NSK, FAG, Timken, KOYO, and NACHI. All versions share the same 30×72×19mm dimensions and are interchangeable in most applications. See the cross-reference table above for detailed comparisons.