NJ328-ECJ bearing: complete specifications & equivalents

The NJ328-ECJ is a ISO 15 radial bearing sized 140 x 300 x 62 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 = 300 mm d = 140 B = 62 mm side section front view
Principal dimensions: bore d 140 mm, outer diameter D 300 mm, width B 62 mm. Schematic, not to scale.

Specification table

ParameterValue
Brand SKF
Bore diameter d 140 mm
Outer diameter D 300 mm
Width B 62 mm
Material GCr15
Seal / shield open
Internal clearance CN
Tolerance class P0
Cage steel, stamped ribbon (J-type)
Basic dynamic load rating C 780 kN
Basic static load rating C0 830 kN
Fatigue load limit Pu 88 kN
Reference speed (thermal) 2400 rpm
Limiting speed (mechanical) 2800 rpm
Operating temperature -40 to +120 °C
Mass 20000 g
Manufacturer designation SKF NJ 328 ECJ
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 & NJ300-series range

Bore d 5.512 in
Outer diameter D 11.811 in
Width B 2.441 in
ISO bore code 28
Radial section height (D−d)/2 80 mm
Smallest bore in NJ300-series 17 mm
Largest outer diameter in NJ300-series 500 mm
Width range across NJ300-series 14–95 mm
Bore position in NJ300-series (smallest first) 23 of 29
Bore above smallest NJ300-series size 123 mm

Cross references & equivalents

Equivalent modelBrandMatch levelNote
NU328-ECM SKF full
Dimensions and internal design equivalent — standard interchange.
Same ISO 15 envelope 140×300×62 mm and equivalent catalogue ratings; the NU execution differs in flange/retaining-ring configuration — boundary-dimension interchangeable, but axial-locating behaviour is not identical.
NUP328-ECM SKF full
Dimensions and internal design equivalent — standard interchange.
Same ISO 15 envelope 140×300×62 mm and equivalent catalogue ratings; the NUP 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 NJ328-ECJ model number is decoded

NJ328-ECJ is the 140 mm bore entry in the NJ300 range: a 140×300×62 mm single-row caged cylindrical roller bearing with a pressed sheet-steel window-type cage, rated C 780 kN / C0 830 kN. Reading the NJ prefix: two integral flanges on the inner ring and no flanges on the outer ring; the inner ring retains the roller set. This makes the execution able to locate the shaft axially in one direction; an HJ angle ring on the opposite side converts it into two-direction location. Reading the order-string suffix ECJ: the E-design execution with a pressed sheet-steel window cage, for positions where polymer cages are temperature- or lubricant-limited. Load-per-bore for the 140 mm seat is about 5.57 kN/mm, typical of dimension series 3 (medium-section ISO 15 envelope); use C0 830 kN for static checks such as crane hook blocks standing under load. Mounting: orient the inner-ring flange side toward the axial load direction; if an HJ angle ring is used, verify its fit and clearance before locking the arrangement. A 140 mm seat normally takes a m6 interference with an H6 housing bore when the inner ring rotates.

Typical equipment & failure modes

Common applications

  • offshore drawworks shafts
  • large rolling-mill drive trains
  • marine propulsion line shafts
  • heavy turbogenerator rotor 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
  • cage pocket wear from roller skew at light load
  • cage pocket wear from roller skidding at insufficient radial load or during start-up before oil film build-up
  • roller-end scoring from inadequate oil flow in the roller-raceway contact
  • edge-loading fatigue after shaft deflection beyond the 3–4 minute alignment limit
  • edge loading from shaft deflection beyond the bearing alignment limit (≈ 3-4 minutes of arc for single-row CRB)

Selection pitfalls — read before you substitute

  • Do not use a NJ bearing where two-direction axial location is required without an HJ angle ring
  • The dimension series 3 (medium-section ISO 15 envelope) envelope is shared with the N/NU/NJ/NUP executions of 328, but flange configuration and axial-locating behaviour differ — quote the full SKF NJ 328 ECJ and do not substitute rib styles without checking the shaft locating scheme.
  • Shaft and housing fillets must clear the bearing chamfers; an oversized radius tilts the 62 mm-wide ring and concentrates load.
  • Catalogue reference and limiting speeds are different criteria: observe the mechanical ceiling even when thermal calculations allow more.
  • The 780/830 kN ratings are SKF catalogue 17000 (2018) values for the ECJ 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 NJ328-ECJ?

SKF NJ 328 ECJ is a single-row caged cylindrical roller bearing with 140 mm bore, 300 mm OD and 62 mm width per ISO 15. SKF lists C 780 kN, C0 830 kN, Pu 88 kN, reference speed 2,400 r/min and limiting speed 2,800 r/min, mass about 20000 g.

What does the NJ designation and ECJ suffix mean?

The ECJ suffix marks the E-design execution with a pressed sheet-steel window cage, useful where polymer cages are temperature- or lubricant-limited. Structurally this execution has two integral flanges on the inner ring and no flanges on the outer ring; the inner ring retains the roller set.

Can NJ328-ECJ take axial load and locate the shaft?

In one direction only, via the two inner-ring flanges. Add an HJ angle ring on the opposite side for two-direction location.

How does NJ328-ECJ 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.