61884 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 61884 model number is decoded

In the 61800-series (diameter series 8 of ISO 15) the last two digits encode the bore: 61884 carries bore code 84 = 420 mm. Outside diameter 520 mm and width 46 mm come from the ISO 15 boundary-dimensions general plan. With no seal suffix the bearing is open: no shields or seals are fitted and lubrication is supplied by the application. For normal-load mounting with a rotating inner ring on a 420 mm shaft, typical catalogue practice is a m6 shaft seat with an H7 housing bore — verify against the actual load direction and magnitude. 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

• Large bores like the 420 mm of 61884 demand clean, burr-free seats; one raised burr under a ring this size cocks the bearing and concentrates load at the raceway edge, cutting life drastically.
• The 618xx thin section at 420 mm bore has only a 50.0 mm radial section height: it saves space but is highly sensitive to misalignment, shaft deflection and shock loads — verify shaft stiffness before choosing it over a 6284.
• The open 61884 has no lubricant retention: grease escapes and contaminants migrate straight into the 420×520×46 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
• Storage matters for open bearings: 61884 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 420 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.
• Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 46 mm-wide ring of 61884 drags the lip and overheats it.
• The open 61884 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.
• The 420 mm bore places 61884 in NTN's upper maximum-size range; at this diameter the bearing mass is substantial and mounting requires induction heating of the inner ring (max 120 °C) with a mechanical puller. NTN supplies a machined brass cage (suffix M) and expects oil lubrication with a defined relubrication interval.
• NTN lists the grease limiting speed at 1000 r/min for 61884; this is a large-section size where the pressed-steel cage is speed-limited — NTN recommends the machined brass cage (suffix M) and oil lubrication for any continuous operation above this figure.
• NTN rates 61884 at 288 kN dynamic (C) and 405 kN static (C0), 12.4 kN fatigue load limit Cu; this is an upper heavy-load rating where the pressed-steel cage is not recommended — NTN supplies a machined brass cage (suffix M) and the static C0 must be verified against any shock or lifting loads the bearing sees during mounting.
• At 21600 g (21.6 kg), 61884 is a very heavy bearing where handling and mounting method directly affect service life; NTN requires induction heating of the inner ring (max 120 °C), a mechanical puller for removal, and a defined lifting procedure to avoid damaging the machined brass cage.
• The 420×520×46 mm envelope of 61884 gives a D/d ratio of 1.24 and only 50.0 mm radial section height — this is an ultra-thin section where shaft deflection and housing ovality directly load the ball-raceway contact; verify shaft stiffness (target deflection under 0.05 mm) before specifying it over a 62-series.
• The 288/405 kN load ratings, 12.4 kN fatigue load limit Cu NTN lists the grease limiting speed at 1000 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 21600 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6884 on the 420×520×46 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61884 in a rated drive.
• Two NTN bearings of the same designation from different production lots can carry minor internal-geometry revisions; for paired or preloaded arrangements on one shaft, order a single lot through the NTN distributor.
• 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.