NNU4924K 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 NNU4924K model number is decoded

NNU4924K is an NTN NNU cylindrical roller bearing: two integral ribs on the outer ring and a ribless, separable inner ring — a non-locating bearing that lets the shaft float axially, inside the 120×165×45 mm ISO 15 envelope. Digit by digit, NNU4924K reads as NNU (double row, ribbed outer ring, separable inner), ISO 15 series, and bore 120 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 NNU4924K at high speed skids its rollers and smears the raceway; spring preload or the rotor weight typically covers the requirement in motors and pumps. Equivalent-load planning treats NNU4924K as a pure radial bearing: keep P below 203 kN at the required L10, and let a paired angular-contact or thrust part carry any sustained axial component. Provide axial location with an adjacent locating bearing rather than expecting the float cylindrical set to hold thrust on the 120 mm shaft.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• At 120 mm bore, oil-lubricated arrangements toward 4,200 r/min need positive flow and drain design; the 2630 g NNU4924K ring stores enough heat that grease-only duty needs a careful relubrication calculation.
• Do not replace NNU4924K with a deep-groove ball bearing on rating alone: line contact gives 203 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 EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 203/360 kN pair here belongs to NNU4924K as printed, not to the bare size.
• The 45 mm width and abutment faces must be square to the axis; a tilted spacer concentrates load across the roller set and shows as uneven raceway polish on the 120 mm inner ring.
• Do not replace NNU4924K with a deep-groove ball bearing on rating alone: line contact gives 203 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 203/360 kN ratings, 39.5 kN Pu and 2630 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NNU4924K (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.