N238 bearing: complete specifications & equivalents

Specification table

Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203E) · extracted 2026-10-01

Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203E); NTN® is a trademark of NTN Corporation, used here for identification only — mpnbase is not an authorized NTN distributor. Boundary dimensions are ISO 15 interchangeable; current production values may differ, verify at ntnglobal.com.

Cross references & equivalents

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 N238 model number is decoded

N238 is the standard section of the NTN N200 dimension series for a 190 mm shaft — 615 kN of basic dynamic capacity in a 20800 g, open bearing. On the NTN nameplate N states which ring carries the ribs, which determines whether N238 floats or locates; the numeric remainder is the ISO 15 series and 190 mm bore reference, not a fit or clearance instruction. Minimum radial load matters: an unloaded N238 at high speed skids its rollers and smears the raceway; spring preload or the rotor weight typically covers the requirement in motors and pumps. Rating life at 615 kN C assumes clean oil and adequate film; the 70 kN Pu floor means contamination derating — not the C rating alone — governs adjusted life in dusty gearboxes. On N arrangements confirm which ring is separable before heating: forcing the ribbed ring off over the roller complement damages the cage and rib faces.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• At 190 mm bore, oil-lubricated arrangements toward 2,200 r/min need positive flow and drain design; the 20800 g N238 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
• Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 340 mm race brinells and releases as vibration within hours.
• Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 340 mm race brinells and releases as vibration within hours.
• Open N238 units need application-supplied sealing and a defined lubricant schedule; film thickness is the first failure mode for line contact when viscosity drops at the 190 mm contact.
• Do not replace N238 with a deep-groove ball bearing on rating alone: line contact gives 615 kN radial capacity but the bearing cannot carry the thrust duty a ball bearing can and misalignment tolerance is only 3–4 arc-minutes.
• The 615/770 kN ratings, 70 kN Pu and 20800 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for N238 (standard execution); other makes sharing the ISO 15 envelope revise internal geometry without changing the order number, so keep the 2203E reference with the specification for critical drives.