NNU4936K 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 NNU4936K model number is decoded

In NTN Ball and Roller Bearings CAT.No.2203E, NNU4936K appears as a 180 mm bore single-row cylindrical roller bearing (510 kN C / 965 kN C0) with a machined or stamped steel cage per the precision execution, listed to the ISO 15 boundary plan. Reading the code: NNU for the double-row precision type, then the ISO 15 diameter/width series and the bore code — ×5 = 180 mm (00–03 use the 10/12/15/17 exception table). Double-row NNU precision cylindrical roller bearing: ribbed outer ring with a separable inner ring, two roller rows for high radial stiffness on machine-tool spindles; the K suffix is a 1:12 tapered bore — mounted on a tapered seat or adapter sleeve and driven up to a precise radial clearance/preload; precision classes P5/P4/P2 and clearance are ordered separately. The 2.8 kN-per-mm-bore figure (510 kN over 180 mm) lets a NNU4936K interchange candidate be screened quickly against the same-envelope ball or roller alternatives. Keep the open bearing wrapped until fitting: the line-contact raceways of the 180 mm bore indent under a single hard particle, and the steel cage provides no sealing of its own.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• At 180 mm bore, oil-lubricated arrangements toward 2,700 r/min need positive flow and drain design; the 9460 g NNU4936K ring stores enough heat that grease-only duty needs a careful relubrication calculation.
• Grease limiting speed 2,300 r/min and oil 2,700 r/min are different limits for NNU4936K: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
• The EA high-capacity roller complement changes the load figure versus the basic execution of the same number; the 510/965 kN pair here belongs to NNU4936K as printed, not to the bare size.
• Grease limiting speed 2,300 r/min and oil 2,700 r/min are different limits for NNU4936K: the first is the cage/lubricant mechanical ceiling, the second assumes real oil flow rather than an oil bath.
• The 69 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 180 mm inner ring.
• The 510/965 kN ratings, 93 kN Pu and 9460 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for NNU4936K (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.