6056-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 6056-NTN model number is decoded

In the 6000-series (diameter series 0 of ISO 15) the last two digits encode the bore: 6056 carries bore code 56 = 280 mm. Outside diameter 420 mm and width 65 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 280 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

• Mount this 280 mm bore bearing by heating the inner ring (induction heater, max 120 °C) — never drive it home through the outer ring or balls, that brinells the raceways.
• The 60xx extra-light section at 280 mm bore uses a smaller 420 mm OD than a 6256; load ratings are lower, so do not replace a failed 62-series bearing with a 60-series without re-rating the load.
• The open 6056-NTN has no lubricant retention: grease escapes and contaminants migrate straight into the 280×420×65 mm raceway, so specify a sealed arrangement for dusty or washdown duty.
• Storage matters for open bearings: 6056-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.
• Axial location must clamp the ring face, not the seal area: a shoulder or circlip bearing on the seal side of the 65 mm-wide ring of 6056-NTN drags the lip and overheats it.
• Assign fits by which ring rotates: an interference shaft fit for a rotating inner ring; if the outer ring rotates instead, reverse the logic — a loose rotating ring creeps and frets its seat.
• The open 6056 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 280 mm bore places 6056 in NTN's extra-large range; the pressed-steel cage is not recommended at this diameter and NTN supplies a machined brass cage (suffix M) as the standard offering. Speed ratings are low, housing alignment is critical, and oil lubrication with a defined relubrication interval is mandatory — consult NTN engineering before sizing.
• NTN lists the grease limiting speed at 1400 r/min for 6056; 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 6056 at 360 kN dynamic (C) and 420 kN static (C0), 16.9 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 31000 g (31.0 kg), 6056 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 280×420×65 mm envelope of 6056 gives a D/d ratio of 1.50 and 70.0 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 360/420 kN load ratings, 16.9 kN fatigue load limit Cu NTN lists the grease limiting speed at 1400 r/min for this designation; oil-mist or jet lubrication raises the ceiling but requires a sealed-housing review. and 31000 g mass here are NTN Ball and Roller Bearings CAT.No.2203-3/E figures for 6056 on the 280×420×65 mm ISO 15 envelope; internal geometry and ratings legitimately differ between brands, so re-verify before substituting another manufacturer's 6056 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.
• Standard catalogue stock of 6056 is the general-purpose execution; for low-noise motor duty NTN offers low-torque seal and special-grease variants in this size class, which are separate order numbers.