N328 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 N328 model number is decoded

NTN lists N328 on the 140×300 mm envelope, 62 mm wide: a line-contact radial bearing with a pressed sheet-steel cage and a grease limiting speed of 2,300 r/min. On the NTN nameplate N states which ring carries the ribs, which determines whether N328 floats or locates; the numeric remainder is the ISO 15 series and 140 mm bore reference, not a fit or clearance instruction. NTN ships these bearings open with normal (CN) radial clearance and P0 tolerance as standard; precision classes and C3/C4 clearance are separate order suffixes, not part of N328. Rating life at 685 kN C assumes clean oil and adequate film; the 72 kN Pu floor means contamination derating — not the C rating alone — governs adjusted life in dusty gearboxes. Heat the inner ring to max 120 °C for the 140 mm interference fit and support the ring face square during fitting; cocking over a keyway brinells the raceway before first rotation.

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• At 140 mm bore, oil-lubricated arrangements toward 2,700 r/min need positive flow and drain design; the 20700 g N328 ring stores enough heat that grease-only duty needs a careful relubrication calculation.
• The N rib arrangement is not interchangeable with another prefix on the same 140 mm seat: inner ring ribbed, outer ring ribless. Swapping NU for NJ changes axial location behaviour even though the 300×62 mm envelope matches.
• If the shaft must be located both ways, do not use N328 alone: pair it with a locating bearing or specify the NUP execution with the matching loose rib ring from the 2203E table.
• Wide (22/23) and light (10/49) executions at 140 mm bore share bore but not OD/width; check the full N300 series code before substituting, because housing and shoulder geometry will not interchange.
• Never press either ring through the roller complement when fitting: mounting force goes through the ring faces, or the 300 mm race brinells and releases as vibration within hours.
• The 685/745 kN ratings, 72 kN Pu and 20700 g mass are NTN Ball and Roller Bearings CAT.No.2203E values for N328 (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.