NUP2306-ECP bearing: complete specifications & equivalents

The NUP2306-ECP is a ISO 15 radial bearing sized 30 x 72 x 27 mm (bore x OD x width). Verify dimensions against the official catalog before ordering.

Bearing dimension schematic Front view shows outer diameter D and bore d; side section shows width B. D = 72 mm d = 30 B = 27 mm side section front view
Principal dimensions: bore d 30 mm, outer diameter D 72 mm, width B 27 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 30 mm
Outer diameter D 72 mm
Width B 27 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage polymer (PA66 glass-fibre reinforced)
Basic dynamic load rating C 83 kN
Basic static load rating C0 75 kN
Fatigue load limit Pu 9.65 kN
Reference speed (thermal) 11000 rpm
Limiting speed (mechanical) 12000 rpm
Operating temperature -40 to +120 °C
Mass 540 g
Manufacturer designation SKF NUP 2306 ECP
Standard ISO 15
Catalog version SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings
Last verified 2026-09-26

Source: catalog reference (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings) · extracted 2026-09-26

Parameters extracted from the official SKF Rolling Bearings catalogue (SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings); SKF® and SKF Explorer® are trademarks of AB SKF, used here for identification only — mpnbase is not an authorized SKF distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at skf.com.

Dimensions in inches & NUP2300-series range

Bore d 1.181 in
Outer diameter D 2.835 in
Width B 1.063 in
ISO bore code 06
Radial section height (D−d)/2 21 mm
Smallest bore in NUP2300-series 20 mm
Largest outer diameter in NUP2300-series 300 mm
Width range across NUP2300-series 21–102 mm
Bore position in NUP2300-series (smallest first) 3 of 21
Bore above smallest NUP2300-series size 10 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
NJ2306-ECP SKF full
Dimensions and internal design equivalent — standard interchange.
Same ISO 15 envelope 30×72×27 mm and equivalent catalogue ratings; the NJ execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical.
NU2306 SKF full
Dimensions and internal design equivalent — standard interchange.
Same ISO 15 envelope 30×72×27 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical.
NU2306 SKF full
Dimensions and internal design equivalent — standard interchange.
Same ISO 15 envelope 30×72×27 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical.

Interchange levels: full standard interchange · partial verify parameters · verify manual confirmation required. Links resolve to the equivalent model's specification page where available.

How the NUP2306-ECP model number is decoded

SKF NUP 2306 ECP is a single-row caged cylindrical roller bearing sized 30×72×27 mm — a dimension series 23 (medium-section, wide), listed in SKF catalogue PUB BU/P1 17000 ch. 6.1. Structurally, the NUP design has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring. In arrangement terms it is a locating bearing that positions the shaft axially in both directions while keeping the cylindrical-roller radial capacity. The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. The glass-fibre reinforced polyamide (PA66) window-type cage is reflected in the published speeds and temperature limits. Selection arithmetic: C0/C ≈ 0.90 (75 against 83 kN), and the Pu figure 9.65 kN is the fatigue load-limit floor for the SKF life equation; the catalogue lists 11,000 r/min thermal reference speed and 12,000 r/min mechanical limiting speed. Mounting: the loose inner-ring flange must be fitted on the correct side and retained by the shaft abutment; never omit it during reassembly or the bearing loses its two-direction locating function. A 30 mm seat normally takes a k5 interference with an H7 housing bore when the inner ring rotates.

Typical equipment & failure modes

Common applications

  • medium industrial gearbox shafts
  • electric-motor shafts in pumps and fans
  • compressor crank and rotor shafts
  • machine-tool radial spindle supports

Known failure patterns

  • inner-ring raceway spalling from overload or contamination in the line-contact hertz zone
  • outer-ring raceway fatigue after extended service at loads above the catalogue L10 rating
  • polymer cage softening above 120 °C
  • cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up
  • surface distress (micro-pitting) when the EHL film falls below the composite roughness at high specific load
  • edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit
  • brinelling from static overload or impact during handling and mounting

Selection pitfalls — read before you substitute

  • Do not use a NUP bearing where a floating non-locating bearing is required — the loose inner flange makes it a locating bearing
  • The dimension series 23 (medium-section, wide) envelope is shared with the N/NU/NJ/NUP executions of 2306, but flange configuration and axial-locating behaviour differ — quote the full SKF NUP 2306 ECP and do not substitute rib styles without checking the shaft locating scheme.
  • Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.
  • Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 27 mm-wide ring and concentrates load.
  • The 83/75 kN ratings are SKF catalogue 17000 (2018) values for the ECP execution; re-verify against the current catalogue for critical drives and keep the catalogue version with the specification.

Frequently asked questions

What are the dimensions and catalogue data of NUP2306-ECP?

SKF NUP 2306 ECP is a single-row caged cylindrical roller bearing with 30 mm bore, 72 mm OD and 27 mm width per ISO 15. SKF lists C 83 kN, C0 75 kN, Pu 9.65 kN, reference speed 11,000 r/min and limiting speed 12,000 r/min, mass about 540 g.

What does the NUP designation and ECP suffix mean?

The ECP suffix marks the E-design execution with a glass-fibre reinforced polyamide (PA66) cage, limited to 120 °C continuous. Structurally this execution has two integral flanges on the outer ring plus one integral flange and one loose flange ring on the inner ring.

Can NUP2306-ECP take axial load and locate the shaft?

Yes, in both directions: the integral inner flange plus the loose flange ring close both axial paths. Do not pair it with another locating bearing without thermal clearance.

How does NUP2306-ECP compare with the other executions in the same envelope?

The N/NU/NJ/NUP executions share the ISO 15 envelope and load ratings but differ in flange arrangement and axial-locating behaviour; quote the exact order number.

What limits the service life of this bearing most often?

Line-contact fatigue above the L10 rating, cage wear at light loads and high temperatures, and edge loading from misalignment beyond about 3–4 minutes of arc are the typical failure drivers.

Reviewed & verified by the MPN Base engineering desk against source catalog SKF PUB BU/P1 17000/1 EN (Oct 2018), ch. 6.1 single-row cylindrical roller bearings on 2026-09-26. Read our editorial & correction policy.