6411-NTN bearing: complete specifications & equivalents

Specification table

Source: catalog reference (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)) · extracted 2026-09-25

Parameters extracted from the official NTN Ball and Roller Bearings catalogue (NTN Ball and Roller Bearings CAT.No.2203-3/E (2024)); 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 6411-NTN model number is decoded

6411 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the heavy 64xx section (diameter series 4 of ISO 15), multiplying bore code 11 by five gives the 55 mm bore; the 140 mm outside diameter and 33 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 55 mm shaft under normal load, catalogue practice seats it on a k5 shaft fit with an H7 housing bore — confirm against the actual load direction and magnitude before committing. In the NTN catalogue this open execution carries the bare designation; protected variants are ordered separately with suffixes ZZ (shields), LLB/LLF (non-contact seals), LLH (low-torque contact seal) and LLU (contact seal).

Typical equipment & failure modes

Selection pitfalls — read before you substitute

• Interference on a 55 mm shaft plus running heat consumes radial clearance: where the shaft runs hot or the fit is tight, order 6411 with C3 clearance and re-check the residual value after mounting.
• The 64xx heavy section at 55 mm bore (140 mm OD) is built for high-load, lower-speed duty; specifying it in a high-rpm motor gives excess heat and short grease life — use 62/63 there.
• The open 6411-NTN has no lubricant retention: grease escapes and contaminants migrate straight into the 55×140×33 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
• Storage matters for open bearings: 6411-NTN leaves the factory with rust preventive only, so clean it and apply the service grease at assembly even if the rings look oily from the wrapper.
• A 55 mm bore listing showing the right d/D/B but no standard or precision-class reference may be a loose-tolerance import; measure bore/OD spread before fitting it to a machined shaft.
• Grease compatibility is not guaranteed between fills: mixing lithium and polyurea thickeners in a 6400-series position can soften the mixture and leak — clean out the old fill before switching grease types.
• The open 6411 has no integral sealing; in the NTN 2203 catalogue the protected variants carry suffixes ZZ (non-contact steel shields), LLB/LLF (non-contact rubber seals), LLU (contact rubber seals) and LLH (a low-torque contact seal with higher speed capability than LLU). A JR or JRX suffix (printed for some thin-section sizes) denotes a pressed-steel cage, not a seal.
• At 55 mm bore 6411 is in NTN's upper general-purpose range; the pressed-steel cage is standard but mid-section 63xx sizes at this bore can be ordered with a machined brass cage (suffix M) for heavy-shock or very-low-speed duty — confirm cage material with the NTN channel if the application sees impact loads.
• At 5200 r/min the grease limiting speed for 6411 covers medium-duty industrial drives; the open or shielded execution can run continuously at this speed with standard lithium-soap grease.
• At 98.5 kN dynamic load rating (C) and 54 kN static (C0), 4.2 kN fatigue load limit Cu, 6411 is a heavy-load bearing for industrial gearboxes and large conveyors; NTN expects a machined brass cage (suffix M) at this rating for shock duty, and the static C0 must be checked against any mounting or lifting loads.
• At 2290 g (2.3 kg), 6411 needs mechanical handling for mounting; NTN recommends induction heating the inner ring (max 120 °C) rather than pressing cold, and a lifting eye if the housing is pre-assembled.
• The 55×140×33 mm envelope of 6411 gives a D/d ratio of 2.55 and 42.5 mm radial section height — a heavy section built for high-load, lower-speed duty; specifying it in a high-rpm motor generates excess heat and shortens grease life, so prefer a 62/63-series there.
• The 98.5/54 kN load ratings, 4.2 kN fatigue load limit Cu NTN lists the grease limiting speed at 5200 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 2290 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6411 on the 55×140×33 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6411 in a rated drive.
• Factory-fill grease in NTN sealed units is a general-duty lithium-soap grease; food-grade, low-temperature and high-temperature fills are request options at order time, because LLU/LLB units are not meant to be opened and re-greased in the field.
• NTN date-codes its packaging; rotate stock first-in-first-out, because the grease inside sealed units ages on the shelf — after three to five years of storage, check the grease condition before putting the bearing into service.