61930-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 61930-NTN model number is decoded

61930 is supplied open, without shields or seals, so the arrangement around it must supply and retain the lubricant. Within the thin 619xx section (diameter series 9 of ISO 15), multiplying bore code 30 by five gives the 150 mm bore; the 210 mm outside diameter and 28 mm width follow the same boundary-dimension plan. For a rotating inner ring on a 150 mm shaft under normal load, catalogue practice seats it on a m6 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

• At 150 mm bore the ring mass is significant: heat 61930 on an induction heater (max 120 °C), never over an open flame, and plan puller access or a withdrawal sleeve now for the day it has to come off again.
• The 619xx thin section at 150 mm bore (30.0 mm section height) cannot shrug off the misalignment a standard section tolerates; keep the housing bores round and aligned, or edge contact will spall the raceways early.
• Storage matters for open bearings: 61930-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.
• Open bearings tolerate the highest speeds in the 61900-series but need a defined regreasing interval; run-to-failure lubrication is the dominant cause of early failure in open 61930 units.
• The housing bore for the 210 mm OD should be round within IT7; an oval bore pinches the outer ring of 61930-NTN and shows up later as two-point loaded raceway wear.
• Never mix components between two 61930-NTN units: rings, cage and balls are factory-matched and are not field-interchangeable, even between identical designations.
• The open 61930 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 150 mm bore places 61930 at the lower end of NTN's large-size range; at these diameters the pressed-steel cage is speed-limited and NTN commonly supplies a machined brass cage (suffix M) as an option. Verify cage material and relubrication interval with the NTN distributor, and do not extrapolate small-bore speed ratings to this size.
• NTN lists the grease limiting speed at 3000 r/min for 61930; this is a large or heavy-section size where centrifugal force and cage inertia cap the speed — for higher shaft speeds either step to a smaller bearing on the same bore or consult NTN for an oil-lubricated, machined-cage variant.
• At 94 kN dynamic load rating (C) and 90.5 kN static (C0), 4.55 kN fatigue load limit Cu, 61930 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 2470 g (2.5 kg), 61930 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 150×210×28 mm envelope of 61930 gives a D/d ratio of 1.40 and 30.0 mm radial section height — this thin section saves space but is sensitive to misalignment and shock; confirm the housing stays round within IT7 and the shaft does not deflect past the raceway contact angle under load.
• The 94/90.5 kN load ratings, 4.55 kN fatigue load limit Cu NTN lists the grease limiting speed at 3000 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 2470 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6930 on the 150×210×28 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 61930 in a rated drive.
• Order the C3 internal-clearance version (61930 with C3 after the seal code) when the shaft fit is tight or the shaft-to-housing temperature gradient exceeds roughly 10 °C — the residual clearance after mounting, not the catalogue CN figure, decides service life.
• 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.