NN4956 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 NN4956 model number is decoded

For pure radial duty on a 280 mm shaft NTN supplies NN4956: two integral ribs on the outer ring and a ribless, separable inner ring; the open execution is rated 1,400 r/min on grease and 1,700 r/min on oil. Digit by digit, NN4956 reads as NN (double row, ribbed inner ring, separable outer), ISO 15 series, and bore 280 mm; trailing letters such as EA or E mark the cage/capacity execution and are part of the order number. Minimum radial load matters: an unloaded NN4956 at high speed skids its rollers and smears the raceway; spring preload or the rotor weight typically covers the requirement in motors and pumps. Speed ratio check: limiting 1,400 r/min is .82 of the 1,700 r/min oil value for NN4956; grease-churn heating closes that gap as fill quantity rises. Provide axial location with an adjacent locating bearing rather than expecting the float cylindrical set to hold thrust on the 280 mm shaft.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• At 280 mm bore, oil-lubricated arrangements toward 1,700 r/min need positive flow and drain design; the 30200 g NN4956 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
• The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 1030/2200 kN pair here belongs to NN4956 as printed, not to the bare size.
• Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 380 mm race brinells and releases as vibration within hours.
• Open NN4956 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 280 mm contact.
• Do not replace NN4956 with a deep-groove ball bearing on rating alone: line contact gives 1030 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 1030/2200 kN ratings, 187 kN Pu and 30200 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NN4956 (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.